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NSCA 2014 Annual Meeting

Journal of Strength & Conditioning Research: December 2014 - Volume 28 - Issue - p S1–S130
doi: 10.1519/JSC.0000000000000655
Abstracts

Thursday Podium Presentations

Thursday, July 10, 2014, 8:30 AM–8:45 AM

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1. Comparisons of Static and Dynamic Balance Performance Between Strength Trained and Untrained Individuals

M. Bryanton,1 A. Remaud,2 and M. Bilodeau3

1School of Human Kinetics, University of Ottawa/Bruyere Research Institute; 2Bruyere Research Institute; and 3School of Rehabilitation Sciences, University of Ottawa/Bruyere Research Institute

*Award Eligible—Doctoral Student Research Award for an outstanding podium abstract presentation.

Purpose: The purpose of this study was to compare changes in static and dynamic balance performance when visual and/or somatosensory input is altered between resistance-trained and untrained individuals. Methods: Five resistance-trained and 4 untrained young adults (mean ± SD; age = 25.7 ± 2.6 years; height = 169.6 ± 13.2 cm) performed static and dynamic postural tasks on a force platform under several combinations of visual (eyes open [EO] and eyes close [EC]) and somatosensory (stable [S] and compliant foam [F] surface) conditions. Each testing session consisted of 3 postural tests: (a) quasi-static quiet standing under 4 sensory conditions (EO-S, EC-S, EO-F, EC-F) with feet together for 30 seconds; (b) limits of stability (LOS) testing under the same previous 4 conditions, which involved maximal anterior and posterior voluntary shifting of the centre of pressure (COP), where participants were asked to maintain maximal lean positions for 10 seconds; and (c) a dynamic target oriented task, where participants were asked to voluntarily shift their COP to match 8 targets that appeared randomly on a monitor in front of them. This final task was performed on both S and F surface conditions. Statistical analyses included separate mixed-model ANOVAs with one between subject (training status) and one repeated-measure (condition) factors (α = 0.05 a priori). Results: Preliminary results showed that trained and untrained participants had similar postural performance during quiet standing: no significant difference was found between groups when change in sway area (cm2), velocity (cm/s), or variability (cm) from baseline EO-S to the 3 more challenging sensory conditions was taken into account. In contrast, during LOS testing, a significant training status × condition interaction was found: in untrained participants postural stability at maximal COP limits decreased more during EC-S (+155% in sway variability) than during EO-F (+82%), while in trained participants stability declined more during EO-F than EC-S conditions (+152% and +35%, respectively). Lastly, trained participants showed greater postural stability and accuracy during the target orientated balance task compared to the untrained group, regardless of surface compliance (less average COP wandering from straight line distance [cm] and average target overshoot [cm], and faster reaction times [s]). Conclusions: These findings demonstrate that static analyses of balance performance are not predictive of an individual's postural control capabilities during dynamic tasks. Additionally, resistance training may improve one's ability to extract sensory input from somatosensory sources when visual input is removed, thus reducing the reliance of postural control on vision. However, this may only be apparent during dynamic balance assessments or when LOS are stressed. Practical Application: Maintaining one's balance is an essential precursor to functional capabilities as human movement involves dynamic tasks. This is particularly important for individuals experiencing declines in postural control systems such as older adults and the visually impaired. The present findings suggest that strength training interventions may be an effective means to improve functional movement performance, which could potentially decrease risk of falling and injury. Acknowledgments: This research was partially funded by the Canada Foundation for Innovation (CFI).

Thursday, July 10, 2014, 8:45 AM–9:00 AM

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2. Does Fatiguing Light Resistance Exercise Maximize Motor Unit Activity?

D. Looney, W. Kraemer, S. Flanagan, B. Comstock, D. Hooper, M. White, T. Szivak, and W. DuPont

University of Connecticut

*Award Eligible—Master's Student Research Award for an outstanding podium abstract presentation.

Purpose: It has been recently speculated in the world of commercial fitness that training with either light or heavy resistance to failure will result in maximal motor unit activation and thus elicit comparable gains in strength and muscle hypertrophy. This concept has been based upon studies which have shown progressive compensatory recruitment of higher threshold motor units in response to fatigue during submaximal resistance exercise. Therefore, this investigation aimed to determine whether progressive compensatory recruitment during fatiguing light resistance exercise would result in similar maximal motor unit activation as heavy resistance. Methods: Eight resistance trained men (age, 22.8 ± 2.8 years; height, 186.9 ± 7.2 cm; weight, 90.9 ± 7.5 kg; squat 1RM, 142.9 ± 29.0 kg) were assessed using electromyography (EMG) on 2 separate counterbalanced testing days, 1 day performing a drop set protocol (3 consecutive sets to failure at 90, 70, and 50% 1RM) and the other day performing a single set protocol (1 set to failure at 50% 1RM). Results: Sets with higher resistance had significantly greater mean and max EMG amplitude than sets with lower resistance. In addition, there were no differences between the 50% 1RM sets of either protocol despite differences in prior fatiguing stimuli. Conclusions: Motor unit recruitment is primarily determined by the force demands placed upon the muscle by external resistance. Fatiguing contractions will result in increased motor unit activation only to a limited extent. Practical Application: Heavy resistance exercise should be prescribed in training interventions when the desired training outcomes are maximal gains in muscular strength and hypertrophy. Although it may result in other physiological adaptations, light resistance exercise does not recruit motor units to the same extent and therefore is not as appropriate for prescription in these circumstances.

Thursday, July 10, 2014, 9:00 AM–9:15 AM

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3. Relationships Between Medial Gastrocnemius Tendon Stiffness and Lower Limb Stiffness During Unilateral Hopping

J. McMahon, P. Comfort, and S. Pearson

University of Salford

*Award Eligible—Doctoral Student Research Award for an outstanding podium abstract presentation.

Medial gastrocnemius (MG) tendon stiffness has been traditionally measured during maximal isometric plantarflexion and has been shown to be unrelated to lower limb stiffness, which is quantified during functional tasks involving the stretch-shortening cycle (SSC). The lack of association between MG tendon stiffness and lower limb stiffness reported in previous work is possibly due to lower achievable tendon forces and load rates during maximal isometric plantarflexion, as these parameters have been shown to influence the resultant tendon stiffness. Purpose: To examine relationships between MG tendon stiffness and lower limb stiffness (i.e., leg stiffness [Kleg] and ankle stiffness [Kankle]) as quantified during unilateral hopping performed with a range of MG tendon forces and load rates. Methods: Resistance trained males (n = 10, 26.3 ± 8.5 years, 181.9 ± 4.8 cm, 86.4 ± 10.7 kg) performed 3 unilateral hopping trials (each lasting 15 seconds) on an inclined sledge apparatus at 3 frequencies (2.0, 2.5 and 3.0 Hz). Three-dimensional motion, ultrasonography of MG muscle fascicles, and ground reaction forces were simultaneously collected. For each trial, 5 consecutive hops performed within 5% of the prescribed frequencies were analyzed. Sagittal plane joint angles and moments were determined via a combination of motion data, force data and inverse dynamics. Kleg was calculated as the ratio of the peak vertical ground reaction force to the peak leg compression. Kankle was calculated as the ratio of peak joint moment to peak joint angular displacement. Instantaneous MG tendon length was calculated by subtracting MG fascicle length multiplied by cosine of the pennation angle from MG muscle-tendon unit length (as determined from shank segment length and joint angle data). Instantaneous MG tendon force was calculated as 26% of Achilles tendon (AT) force, which was determined as ankle joint moment divided by AT moment arm (derived from ankle joint angle data). MG tendon stiffness was calculated based on the gradient of the tendon force-elongation relationship, measured between 60–100% of peak tendon force. MG tendon load rate was derived from tendon force-time data. Pearson's correlation coefficient was used to determine relationships for pooled mean data calculated for the 3 hopping frequencies. Results: MG tendon stiffness demonstrated significant positive correlations to both MG tendon force (r = 0.90, p < 0.01) and MG tendon load rate (r = 0.74, p < 0.01). Furthermore, MG tendon stiffness was significantly inversely correlated to both Kleg (r = −0.71, p < 0.01) and Kankle (r = −0.66, p < 0.01). Conclusions: MG tendon stiffness showed moderate-high inverse relationships with both Kleg and Kankle, as measured during a functional SSC task. Greater MG tendon stiffness was associated with larger tendon forces and higher tendon load rates. Practical Application: The relationships observed in the present study, highlight the importance of quantifying MG tendon stiffness during the performance of the task for which lower limb stiffness has been determined. This would lead to more accurate interpretation of results derived from lower limb muscle-tendon research and thus, in turn, better application to performance, rehabilitation and training.

Thursday, July 10, 2014, 9:15 AM–9:30 AM

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4. Salivary Biomarker Monitoring of Elite Collegiate Male Basketball Players Across an NCAA Division I Season

M. Andre,1 A. Fry,2 A. Hudy,2 P. Dietz,2 and G. Cain2

1University of Wisconsin–LaCrosse; and 2University of Kansas

*Award Eligible—Doctoral Student Research Award for an outstanding podium abstract presentation.

The ratio between testosterone and cortisol (TC) has been used to monitor training stress and performance in athletes. Purpose: To monitor free testosterone (T), cortisol (C), and the ratio of testosterone to cortisol (TC) in elite male NCAA Division I basketball athletes, weekly, throughout an entire season. Methods: Twelve athletes gave a salivary sample before an afternoon practice in the middle of each week for 30 consecutive weeks, beginning in the pre-season and ending 1 week after the end of post-season competition. Salivary samples were assayed for T and C. Additionally, a composite value composed of Z-scores (COMP) for weekly practice minutes, game minutes, resistance training repetitions, academic stress, and travel stress was used in an attempt to quantify weekly cumulative stress so that an increase in COMP suggested an increase in cumulative stress. One-way RM ANOVA with LSD pairwise comparisons were used to determine which weekly values were different (α = 0.05) from the season average. Results: For T, 10 weeks were different from baseline (5.1 nmol/L). For C, 11 weeks were different from baseline (9.0 nmol/L). For TC, weeks 7 (p = 0.007), 17 (p = 0.007), and 25 (p = 0.005) were different from baseline (TC = 0.69). During Wk7, at the start of regular season play, TC was more than 3 standard deviations (SD) above baseline while COMP was significantly below baseline. During week 17, which was leading into a streak of important conference matches, TC was more than 2.5 SD below baseline while COMP was not different from baseline. During week 25, which was 1 week before the conference tournament, TC was more than 1 SD below baseline while COMP was significantly above baseline. Conclusions: The large increase in TC at week 7 suggested that these athletes were recovered from stressful pre-season training and physiologically prepared for the first week of regular season competition. The decrease in TC at week 17, despite the current win-streak, suggests that the lengthy season was having a physical effect on the student-athletes. Despite a brief 3-game losing streak during weeks 20–21, TC was not significantly impacted. Finally, following a decrease in TC before post-season competition and a trend towards a decrease in week 28 (p = 0.073; 1.5 SD below baseline), the athletes were able to return to hormonal baseline 1 week after the end of the season. Practical Application: Strength and conditioning coaches and sport coaches should be aware of the in-season and post-season stressors of elite collegiate basketball, and should adjust training to allow for optimal recovery. The methods of this study can be used for monitoring fatigue management by assessing how one's athletes adapt to stressful pre-season training and whether or not they recover in time for regular season play, in addition to how the athletes handle the stressors of the competitive season. Acknowledgments: This study was supported by a KU General Research Fund Award # 2301776.

Thursday, July 10, 2014, 9:30 AM–9:45 AM

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5. MTOR Pathway Activation in Skeletal Muscle Is Related to Myosin Heavy Chain Content: Role of Leucine and Whey Supplementation

M. Lane, A. Fry, T. Herda, M. Cooper, P. Gallagher, and J. Semaan

University of Kansas

*Award Eligible—Doctoral Student Research Award for an outstanding podium abstract presentation.

Introduction: Currently limited research has shown a link between intramuscular signaling and muscle fiber types following heavy resistance exercise. Purpose: To determine relationships between resistance exercise-induced MTOR pathway activation and myosin heavy chain content following leucine and whey supplementation. Methods: Twenty recreationally resistance trained men (X ± SD; age = 27.8 ± 2.8 years, height = 1.78 ± 0.07 m, weight = 81.3 ± 11.0 kg) served as subjects. On visit 1, subjects gave a muscle biopsy of the vastus lateralis m. (baseline) to determine baselines for skeletal muscle Akt, mTOR, 4E-BP1, P70S6K, and S6 phosphorylation. Strength was assessed for 10 repetition maximums (RM) on leg press and leg extension machines. On visit 2, subjects were randomized to ingest either leucine + whey protein (10 g + 10 g; supplement) or a non-caloric placebo. Visit 3 was 3–5 days after the baseline session in a double-blind crossover design where subjects were given either the placebo or supplement with the order being randomized. During this visit, 5 sets of 10 RM were performed on the leg press and leg extension. Immediately after completion of each training session, subjects ingested the placebo or the supplement, followed by a muscle biopsy 45 minutes later. The procedure was repeated 7–9 days later utilizing the opposite treatment. SDS-PAGE and western blots were used to quantify total and phosphorylated signaling proteins. SDS-PAGE was used to determine MHC characteristics of each subject. Pearson product-moment correlations were used to determine relationships between MHC characteristics and intramuscular protein signaling (* = α < 0.05, = α < 0.01). Results: Relative MHC expression was 15.6 ± 10.9% type IIx, 50.6 ± 9.7% type IIa, and 33.8 ± 13.2% type I fiber. Correlations between MHC characteristics and intramuscular proteins found that there was a negative correlation with % MHC type I and S6 phosphorylation with supplementation r = −0.63. There was also a positive correlation between % MHC type I and AKT activation during the placebo trial r = 0.50*. Additionally, there was a positive correlation between % MHC type IIa and mTOR phosphorylation in the placebo condition (r = 0.51*) and a positive correlation between % MHC type IIx and S6 phosphorylation (r = 0.60*). Conclusions: Previous research has shown that fast twitch (type IIa and IIx) fibers in a muscle show a greater activation of p70 s6k. This research study did not see the same results, but did show a greater effect of phosphorylation of S6 with exercise plus a supplement. Furthermore the inverse relationship with AKT could possibly be caused by slower signaling cascade activation in slow twitch dominant individuals. Practical Application: In general, regardless of muscle fiber type, heavy resistance exercise increases phosphorylation of intracellular hypertrophic pathway proteins. There also seems to be fiber type specific predispositions for phosphorylation of the mTOR signaling pathway. Further research in this area utilizing both resistance training and supplementation must be performed to discern if there is a long-term fiber type-specific mTOR pathway response to both the chronic and acute training responses. Acknowledgments: This study was funded in part by GNC, Inc.

Thursday, July 10, 2014, 9:45 AM–10:00 AM

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6. Effects of Six Weeks of Aerobic Exercise and CLA Supplementation on Peak Oxygen Uptake, Gas Exchange Threshold, and Respiratory Compensation Point

N. Jenkins,1 S. Buckner,1 J. Goldsmith,1 H. Bergstrom,2 K. Cochrane,1 J. Weir,3 T. Housh,1 and J. Cramer1

1University of Nebraska–Lincoln; 2University of Nebraska; and 3University of Kansas

*Award Eligible—Doctoral Student Research Award for an outstanding podium abstract presentation.

Purpose: This study examined the effects of 6 weeks of aerobic exercise and conjugated linoleic acid (CLA) supplementation on peak oxygen uptake (

), the gas exchange threshold (GET), and the respiratory compensation point (RCP). Methods: Thirty-four untrained to moderately trained men (mean ± standard deviation; age = 21.5 ± 2.8 years; height = 179.3 ± 5.9 cm; mass = 77.2 ± 9.5 kg) completed this double-blind, placebo controlled study and were randomly assigned to either a CLA (Clarinol A-80; n = 18) or placebo (PLA; sunflower oil; n = 16) group. Prior to and following 6 weeks of aerobic training (50%

for 30 minutes, twice per week) and supplementation (8 ml CLA or PLA per day), each subject completed an incremental cycle ergometer test to exhaustion to determine their

, GET, and RCP (expressed as ml·kg−1·min−1 and W). Statistical analyses included separate mixed factorial ANOVAs (condition x time) and ANCOVAs using the pre-training values as the covariates. Results: Table 1 contains the means (±95% confidence intervals), p-values, and partial eta-squared (η[Black Square](2@p)) effect sizes for the mixed factorial ANOVAs. For

, there was a group x time interaction, but there were no differences between the CLA and PLA groups at pre- or post-training and no differences from pre-to post-training for either the CLA or PLA group. The ANCOVA indicated no differences between the adjusted post-training means for

. For GET and RCP, there were no group x time interactions or main effects for group, but there were main effects for time. GET and RCP increased from pre-to post-training for both the CLA and PLA groups. There were no differences between the adjusted post-training means for the CLA and PLA groups for GET or RCP. Conclusions: CLA supplementation did not augment the training-induced increases in GET or RCP, nor were there any effects of CLA or moderate aerobic training on

. In addition, the aerobic training regimen utilized in this study was sufficient to elicit increases in the GET and RCP without affecting

. Practical Application: These data suggested that CLA is unable to enhance the effects of moderate aerobic training on

, GET, or RCP in humans. Furthermore, GET and RCP were sensitive to 12 sessions of moderate aerobic exercise, but

was not. This finding was consistent with previous reports (Burgomaster et al. J Appl Physiol, 98:1985–1990, 2004; McKay et al. J Appl Physiol, 107:128–138, 2009) showing increased lactate threshold, mitochondrial enzyme activity, and muscle glycogen content, as well as lower respiratory exchange ratios during submaximal exercise, without changes in

. Acknowledgments: These data were from a clinical trial funded by Stepan Specialty Products, LLC.

Thursday, July 10, 2014, 10:00 AM–10:15 AM

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7. Impact of T + Supplementation on Strength and Endocrine Markers in Power Athletes

V. Kreipke,1 B. Allman,1 A. Kinsey,1 W. Hyder,1 R. Hickner,2 G. Dubis,2 C. Tanner,2 R. Moffatt,1 and M. Ormsbee1

1Florida State University; and 2East Carolina University

*Award Eligible—Doctoral Student Research Award for an outstanding podium abstract presentation.

Testosterone treatments have been linked to improved performance and body composition; however, potential adverse effects have been reported. Therefore, there has been an increased use of herbal supplementation as a means to naturally boost testosterone. Both the efficacy and safety of these herbal testosterone supplements require further examination. Purpose: The objective of this study was to determine the impact of T + TM (Onnit Labs, Austin, TX) supplementation on strength and endocrine markers in power athletes. Methods: Resistance-trained, male power athletes (n = 28) volunteered to participate in this study. Participants were stratified by total weight lifted for squat, chest press, and deadlift and randomly assigned to either the experimental group (T+; n = 14; age, 21.4 ± 3.3 years; height, 179.1 ± 5.6 cm; body fat, 18.3 ± 4.7%) who ingested T+ (54 Kcal/14 g, 66.3% CHO, 30.1% Protein, 0.08% FAT) or a control group (PL; n = 13; age, 21±3 years; height, 177.6 ± 4.8 cm; body fat, 21.5 ± 6.2) who consumed a placebo (53.2 Kcals/14 g, 95.1% CHO, 0% Protein, 0% FAT). One subject was removed from the study due to non-compliance. Supplements were consumed 20 minutes before each training session and a second dose was consumed 2 hours after training. The supplement dosage was based on participant body mass (those 93.2 kg received 14 g pre and 14 g post). On non-training days, T+ and PL were consumed once with breakfast and once with lunch. Maximal strength (pre/post) and fasting blood samples (pre/mid/post) were collected over the course of the study at the same time of day. Statics: Descriptive data were generated for all variable are expressed as means ± standard deviance. An analysis of variance with repeated measures was used to analyze all data. Results: The T+ group showed greater strength increases over time than the PL group (Table 1). Body composition improved over time (p ≤ 0.05) with no differences between groups. There were no pre to post time or group x time interactions for cortisol, estradiol, testosterone or free testosterone. Two participants reported acne and 2 reported increased libido in the T+ with no side effects reported in PL. Conclusions: In young male, power athletes, 4 weeks of RT and T+ supplementation resulted in significantly greater improvements in total strength and chest press performance than those who supplemented with PL. There were no differences between groups in cortisol, estradiol, total testosterone or free testosterone levels. Practical Application: Trained power athletes may benefit in strength performance after supplementation with T+: however, the mechanism of action does not appear to be due to alterations in serum cortisol, estradiol total testosterone or free testosterone concentrations. Clinical Trials Registration: NCT01971723.

Thursday, July 10, 2014, 10:15 AM–10:30 AM

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8. Professional Men's Basketball Potential and Lower Body Strength and Power

A. Fry,1 M. Lane,1 A. Hudy,1 P. Dietz,1 G. Cain,1 and M. Andre2

1University of Kansas; and 2University of Wisconsin–LaCrosse

Heavy resistance exercise is often prescribed for collegiate basketball players to enhance game performance, but few data are available concerning the transference of lower body strength and power to the opportunity to play professionally after college. Purpose: To determine the qualities of lower body strength and power associated with collegiate players who subsequently play professional basketball. Methods: Data were collected over a 5 year period from members of an NCAA I men's collegiate basketball program (n = 37; X ± SD; age = 20.0 ± 1.4 years, height = 1.98 ± 0.09 m, BW = 94.5 ± 11.8 kg). Lower body strength was determined from 1 repetition maximum (1 RM) tests of the parallel high-bar squat. Maximum lower body squat power was determined from speed squat testing across a load spectrum (30–90% 1 RM) while an external tethered dynamometer or a 3-D video motion capture system quantified barbell power. Subjects were classified in the following groups; NBA (n = 10; drafted or projected draft picks), Pro (n = 8; played or projected to play professionally other than NBA), or None (n = 19; did not play professionally). Repeated measures ANOVA with Tukey's HSD post hoc (*α < 0.10), Spearman ρ correlations, and Cohen's D effect sizes (vs. None group) were used to analyze the results. Results: See table. Discussion: Subjects who subsequently played in the NBA or in professional leagues elsewhere had greater lower body strength and power. This was partly due to their greater body mass, since strength and power relative to body mass was not different between the groups. Even when the RMANOVA did not indicate significant differences, effect sizes consistently indicated moderate to large differences between the NBA and Pro groups when compared to those who did not play professionally. Regardless, body mass and lower body strength and power were related to post-collegiate playing opportunities, with greater values for each related to higher levels of professional play. Practical Application: These data support the importance of lower body strength and power, as well as total body mass, for creating opportunities to play professionally in men's basketball. Each of these variables are readily enhanced with a properly designed strength and conditioning program, with exercises focusing on hypertrophy, and lower body strength and power being a part of a regular training program for this sport.

Thursday Poster Presentations

July 10, 2014, 11:30 AM–1:00 PM

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1. The Effect of Acute Heavy Resistance Exercise on Neutrophils and Myeloperoxidase

A. Sterczala, B. Comstock, S. Flanagan, B. Kupchak, T. Szivak, D. Hooper, D. Looney, M. White, W. DuPont, and W. Kraemer

University of Connecticut

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Resistance exercise has been shown to affect circulating neutrophils, however, the magnitude of the effect is dependent upon the acute program variables including intensity, rest period length, and exercise selection. Given the ability of neutrophils to secrete the oxidative enzyme myeloperoxidase, resistance exercise may induce oxidative stress. Purpose: This investigation analyzed affect of high intensity, multi-joint resistance exercise on neutrophil counts and plasma myeloperoxidase concentrations in resistance-trained individuals. Methods: Eleven resistance-trained men (mean ± SD; age = 24.1 ± 4.5 years; height = 176.8 ± 5.5 cm; weight = 84.6 ± 12.8 kg) performed an acute heavy resistance exercise protocol (AHREP) consisting of 6 sets of 10 repetitions of the back squat. The load utilized began with approximately 80% of their back squat 1RM and was reduced as needed to complete the necessary repetitions. Rest periods of 2 minutes were given following sets 1 and 2, while rest periods of 3 minutes were given following sets 3, 4 and 5. On the testing day, an indwelling cannula was inserted into the antecubital vein from which blood was collected pre, immediately post (IP) and 15, 30, 60 and 120 minutes after completion of the AHREP. Additionally, blood was collected at 24, 48 and 72 hours into recovery. Plasma myeloperoxide (MPO), cortisol, and lactate were measured in duplicate using commercially available ELISAs. Neutrophil counts were performed using flow cytometry as part of a complete blood count with differential. Data were analyzed using repeated measures analysis of variance, and pairwise comparisons were made using Fisher's post hoc test. Results: MPO was significantly increased at IP and 15 minutes after the AHREP and returned to baseline levels within 30 minutes. Neutrophil counts were elevated immediately following the AHREP and neutrophilia persisted through the 120-minute time point. As expected, cortisol and lactate increases were observed acutely following the protocol. No significant differences were observed for any variable between baseline and 24, 48 and 72 values. Observed values are reported in Table 1. Conclusions: High intensity, exhaustive resistance exercise as performed in the AHREP, stimulates an increase in circulating neutrophils and a corresponding increase in the concentration of the oxidative enzyme MPO. The increased plasma MPO concentrations suggest that heavy resistance exercise can cause oxidative stress. Additionally, this investigation provides further evidence of the correlation between elevated cortisol and lactate concentrations and resistance exercise induced neutrophilia. Practical Application: This investigation sheds additional light on immune and oxidative demands of high intensity resistance exercise employing complex, multi-joint exercises. These demands may in turn confer additional beneficial adaptations. Furthermore, the effects of combined oxidative, metabolic and mechanical stress should be considered when determining the recovery needs of athletes.

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2. The Pro-Inflammatory Cytokine Response to Ultra-endurance Cycling in an Extreme Environment

D. Levitt,1 H. Luk,1 A. Duplanty,1 R. Budnar, Jr.,1 A. Fernandez,1 T. Layman,1 A. McKenzie,2 E. Lee,2 L. Armstrong,2 D. Hill,1 B. McFarlin,1 and J. Vingren1

1University of North TX; and 2University of Connecticut

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Introduction: Ultra-endurance exercise, especially under extreme environmental conditions (e.g., high temperature), acutely disrupts homeostasis and results in transient physiological stress. This disruption in homeostasis induces an immune response that is mediated and coordinated by cytokines. T helper cells, subset 1 (TH1), respond to and produce regulatory cytokines that are associated with increased inflammation. Few studies have investigated the changes in circulating TH1 and pro-inflammatory cytokines in response to ultra-endurance exercise in an extreme environment. Purpose: The purpose of this study was to describe the effect of ultra-endurance road cycling (164 km) in a hot environment on TH1 and additional pro-inflammatory cytokines. Methods: Forty-one experienced cyclists (38 men and 3 women; 49.4 ± 8.6 years; 83.0 ± 14.6 kg; 176.1 ± 7.2 cm; 19.7 ± 6.5% body fat) participating in the August 2013 Hotter’N Hell Hundred ride in Wichita Falls, TX were recruited. Participants completed a 164 km bicycle ride in a hot (temperature: 35.3 ± 5.0 °C; humidity: 45.6 ± 14.2%) environment. Blood samples were collected within the 2 hours prior to the ride (PRE, 0500–0700 h) and immediately after event completion (POST). Serum was analyzed for TH1 and pro-inflammatory cytokines: granulocyte macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor-alpha (TNF-α), interferon gamma (IFN-γ), interleukin (IL)-2, IL-12, IL-8, and IL-6. Results: Circulating concentrations of GM-CSF (PRE: 0.57 ± 0.40 pg·ml−1; POST: 0.48 ± 0.36 pg·ml−1), TNF-α (PRE: 0.96 ± 0.25 pg·ml−1; POST: 0.90 ± 0.24 pg·ml−1), and IL-2 (PRE: 0.88 ± 0.37 pg·ml−1; POST: 0.76 ± 0.33 pg·ml−1) decreased significantly (p ≤ 0.05) while circulating concentrations of IL-8 (PRE: 0.88 ± 0.18 pg·ml−1; POST: 1.10 ± 0.18 pg·ml−1) and IL-6 (PRE: 0.60 ± 0.29 pg·ml−1; POST: 1.29 ± 0.25 pg·ml−1) increased significantly from PRE to POST. No change was found for circulating concentrations of IFN-γ or IL-12. Conclusions: A prolonged bout of cycling in a hot environment alters concentration of TH1 and additional pro-inflammatory cytokines. Practical Application: The results show divergent responses between TH1 cytokines (GM-CSF, TNF-α, and IL-2) and other cytokines with pro-inflammatory functions (IL-6 and IL-8). Decreases in the concentrations of GM-CSF, TNF-α, and IL-2 suggest that ultra-endurance cycling in a hot environment inhibits the production of cytokines by TH1 cells, thereby blunting the immediate inflammatory response. IL-6 and IL-8 promote the mobilization of neutrophils from bone marrow into circulation and transmigration into damaged tissue to begin phagocytosis, thus despite the decrease in TH1 cytokines the inflammatory response does not appear to be fully suppressed immediately post exercise. The acute inflammatory response is important to tissue repair and since this response is at least partly suppressed following ultra-endurance cycling in the heat, athletes should take care to not further suppress acute post-exercise inflammatory processes.

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3. The Relationship Between Thyroid Hormones and Commonly Cited Symptoms of Overtraining in Collegiate Female Endurance Runners

J. Nicoll, D. Hatfield, R. Keith, K. Melanson, C. Nasin, and D. Riebe

University of Rhode Island

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Overtraining (OT) is common in endurance sports. Thyroid hormones (TH) are altered by energy imbalances, and these imbalances are often present in female endurance athletes. TH also regulate metabolism, energy production, and therefore they may play a role in commonly cited symptoms of OT in these athletes. Alterations in TH status often occur slowly, and research investigating TH and their relationship in overtrained athletes is sparse. Purpose: The purpose of this study was to investigate relationships in TH and commonly cited symptoms of OT in collegiate track and field (T&F) endurance runners. Methods: Sixteen female track and field middle (MD; n = 9; age: 20.21 ± 1.49 years; height: 167.86 ± 5.04 cm; body mass: 57.97 ± 5.05 kg;

: 53.62 ± 6.04 ml/kg/min) and long (LD; n = 7; age: 20.47 ± 1.53 years; height: 162.48 ± 6.11 cm; body mass: 56.15 ± 5.99 kg;

: 61.94 ± 3.29 ml/kg/min) distance runners participated in a 14 weeks descriptive study. Thyroid stimulating hormone (TSH), triiodothyronine (T3), and thyroxine (T4), were collected at the beginning of the indoor T&F (PRE) and end of the outdoor T&F season (POST). Vertical jump power (VJP) was tested at PRE, MID, and POST season. A fatigue scale was administered weekly, and percent change (ΔRT) in race time (season best vs. championship performance) was calculated. Pearson correlations were performed between TH, fatigue, and performance variables. Significance was set at p ≤ 0.05. Results: There was a significant negative correlation between TSH and VJP at POST season (r = −0.575; p = 0.031). There was a significant correlation between TSH POST and ΔRT (r = 0.623; p = 0.023), indicating there were higher TSH levels in runners who ran slower (and therefore poorer performance) at the end of the season. Specifically in the MD runners there was a significant relationship between TSH and T4 at PRE (r = 0.776; p = 0.040). There were also significant correlations between T3 at PRE and fatigue at week 2 (r = 0.925; p = 0.025). TSH and VJP PRE season were also related (r = 0.989; p < 0.001). Conclusion: Thyroid hormones are potent regulators of metabolism. Circulating thyroid hormones and their association to performance variables may seem to depend on the type of training (i.e., middle vs. long distance training) the athlete performs. Additionally, higher concentrations of TSH at the end of a track and field season my indicate impairments in running performance, such that runners with higher concentrations of TSH were less powerful and ran poorly. TSH may be a useful indicator of overall training status of the endurance athlete. This data should be interpreted with caution as OT is a multifactorial syndrome, however, taken together TH may play an integral role in decreased endurance performance. Practical Application: Practical application of this data suggests TH are related to endurance performance, and to some extent, anaerobic performance as well. To our knowledge, this is the first report utilizing vertical jump power as a marker of overtraining in endurance athletes.

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4. How Many Contractions Are Required to Assess the Electromyographic Amplitude vs. Isometric Force Relationship?

A. Drusch, M. Stock, and B. Thompson

Texas Tech University

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

The results from previous studies have indicated that the electromyographic (EMG) amplitude vs. isometric force relationship is quite linear, with coefficients of determination (R2) as high as 0.90 or greater. This high degree of linearity across a range of submaximal force levels suggests that only a few contractions may be required to study the slope of this relationship. Purpose: The purpose of this investigation was to determine the minimum number of contractions required to assess the linear slope coefficient of the EMG amplitude vs. isometric force relationship. Methods: Ten healthy men (mean ± SD age = 23 ± 2 years) participated in this study, and were familiarized with the testing procedures prior to data collection. For the data collection trial, the subjects performed submaximal trapezoidal isometric contractions of the right leg extensors at each tenth percentile of the maximal voluntary contraction (MVC) value (i.e., 10, 20….90% MVC, etc.) with 2 minutes of rest between each attempt. Throughout testing, bipolar surface EMG signals were detected from the vastus lateralis and vastus medialis, and the root-mean-square (RMS) value of each 4 second constant-force portion was calculated. Bivariate regression analyses were used to determine the linear slope coefficient of the EMG amplitude vs. isometric force relationship (µV RMS/N) for 7 possible combinations that included sequentially higher force levels (i.e., 10–30, 10–40…10–90% MVC etc.) A 2-way (muscle × force combination) repeated measures analysis of variance was used to examine mean differences. Results: There was a significant main effect for force level combination (p = 0.001, partial eta squared = 0.520), but there were no differences between the muscles. The results indicated that when collapsed across the muscles, the linear slope coefficient for the 10–40% MVC condition was significantly less than that for the 10–90% MVC condition (0.189 µV RMS/N vs. 0.239 µV RMS/N; p = 0.035, 95% confidence interval for the mean difference = −0.098 to −0.003), but no further differences were noted. Conclusions: Although the linear slope coefficient for the EMG amplitude vs. isometric force relationship was greatest when force levels corresponding to 10–90% MVC were utilized, exclusion of the higher force levels (e.g., 60–90%) had little influence on the data. Practical Application: The EMG amplitude vs. isometric force relationship has been used in previous studies to assess neural adaptations to strength training and disuse atrophy. Our data suggests that researchers interested in studying these issues do not need to examine a wide variety of force levels since the linear slope coefficient is similar when only a few contractions are performed.

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5. Age-Related Differences in Achilles Tendon Cross-Sectional Area and Thickness

A. Tweedell,1 E. Ryan,1 E. Sobolewski,1 M. Scharville,1 J. Rosenberg,1 C. Kleinberg,1 and B. Thompson2

1The University of North Carolina at Chapel Hill; and 2Texas Tech University

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

The use of ultrasonography to evaluate the age-related changes in Achilles tendon (AT) properties has gained popularity due to its portability and ease of use. Common indices of AT size include AT thickness and cross-sectional area (CSA). However, it is possible that CSA may be a more sensitive measure of age-related changes in AT size. Purpose: The aim of this study was to examine the differences in AT CSA and thickness between young and old recreationally active male participants. Methods: Fourteen old (mean ± SD age, 69.9 ± 3.3 years; mass, 84.1 ± 11.3 kg; stature, 176.1 ± 3.2 cm) and 14 young (age, 19.9 ± 2.7 years; mass, 70.0 ± 9.6 kg; stature, 169.3 ± 16.6 cm) healthy, recreationally active (1–5 hours a week of exercise) male participants volunteered for this study. Participants visited the laboratory on one occasion where ultrasound (US) measurements of the AT were taken with a B-mode US imaging device while participants were in a prone position on a padded table with their right leg fully extended and right foot secured to a vertical post at a 90° ankle angle. CSA was determined by a transverse scan with the US probe placed perpendicular to the AT just proximal to the medial malleolus. A standoff pad and water-soluble transmission gel were placed between skin and probe to decrease potential artifact. CSA was quantified using a continuous trace method around the boundaries of the tendon. Thickness was determined by panoramic US imaging with the probe moving continuously from the AT insertion into the calcaneus to the musculotendinous junction of the gastrocnemius. To ensure the probe moved perpendicular to the skin and along the longitudinal plane, a probe support pad was positioned parallel to the longitudinal axis of the leg. Thickness was measured from the superficial to deep border of the AT just proximal to the medial malleolus and was quantified using a straight line function. All US imaging analyses were performed using Image-J software. Age-related differences in CSA and thickness were examined using independent samples t-tests with the alpha level set at p ≤ 0.05. Results: There was no significant differences in thickness between the young (4.92 ± 0.51 mm) and old (5.11 ± 0.64 mm) men (p = 0.41). However, CSA was larger (p < 0.001) in the old men (66.21 ± 14.83 mm2) when compared to the younger men (40.13 ± 7.90 mm2). Conclusions: The results of this study indicate that CSA may be a more sensitive measure when examining age-related changes in AT size. These findings revealed older men exhibited greater AT CSA which may be indicative of increases in extracellular water content with aging. Practical Application: US imaging is becoming an important diagnostic tool to examine AT properties. Future studies should consider examining AT CSA when examining the influence of training and/or disease on AT size.

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6. The Relationship Between Controlled Arousal Levels and Putting, in Two Different Conditions: A Pilot Study

A. Elumalai, D. Szymanski, J. Szymanski, and J. Parks

Louisiana Tech University

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Introduction: Arousal is a major aspect of many learning theories, and is closely related to concepts such as anxiety, attention, agitation, stress, and motivation. Arousal level is one of the most powerful factors to affect the sports performance of players. The knowledge of an elevated arousal level and its effect on golf putting has led to the use of devices that have been suggested to help golfers learn how to control their arousal levels and potentially improve golf putting performance. According to some research studies, optimal arousal levels play a major role in golf putting success. To reach that optimum arousal level, golfers need to either stimulate stress or control it. Purpose: To determine, if the golfers were more successful with their putting when they were made aware of their optimum arousal level and took measures to maintain it. Methods: Ten NCAA Division I golfers with a handicap of <3 volunteered to be randomly assigned to a control (n = 5) and experiment group (n = 5). All subjects signed an informed consent according to the university's Institutional Review Board. Subjects' mean age was 20.2 ± 1.5 years and played for the same team under the same coach and practice conditions. Subjects were instructed to wear a Zephyr H x M BT heart rate monitor, which detects the time between 2 of the distinctive, large, upward “R” spikes during the QRS complex of heart rate, while putting in 2 conditions. The Mind Meter, an android cell phone application, tracked player's arousal levels by recording the subtle changes in the R-R interval between each heartbeat, displayed as a number between 00 and 99. In the first condition, on a flat practice putting green surface, the subjects were randomly assigned 5 putts each from 3 distances that were 3, 6, and 9 feet from the hole. The data from the Mind Meter was recorded before (stepping towards), during (takeaway), and after (finish) each putt. In the second condition, the arousal levels were raised by changing the emotional factor of the golfers by exposing them to a competition for a prize. The accuracy of the putts during both conditions was monitored by measuring the number of accurate putts and distance between the ball and hole in case of a missed putt. The protocol of both the conditions was repeated for both the groups after the experiment group was made aware of their arousal levels and techniques to control it. The average of arousal levels during the makes and misses was used to determine the relationship between different settings and arousal levels. Correlation and t-test were performed to see the difference of performance between the 2 groups. Results: The putting performance was significantly better (p ≤ 0.05) in the group more aware of their optimum arousal levels. Conclusions: The results suggest that each college player had an individualized optimum arousal level during the different putting conditions. The findings of this pilot study indicate that definitive results regarding the optimum arousal levels in the different conditions require a larger sample size and more data in each condition. For the best putting performance, college golfers should be aware of their own optimum arousal level. Practical Application: Collegiate golfers can potentially improve the success of their putting game during competitions by using the Zephyr H x M BT heart rate monitor to identify their optimum arousal levels when they putt effectively. Further research is needed to determine the relationship of arousal levels and putting in amateur and professional golfers.

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7. Influence of Hamstrings Fatigue on Quadriceps Data During Repeated, Maximal Isokinetic Strength Testing

E. Carrillo, M. Stock, J. Mota, A. Drusch, K. Olinghouse, and B. Thompson

Texas Tech University

*Award Eligible—Undergraduate Student Research Award for an outstanding poster abstract presentation.

Repeated, maximal isokinetic strength testing is often used in research studies. Most notably, the percent decline associated with these data has been used to estimate the percentage of type II muscle fibers for the vastus lateralis. However, it is not clear how the activity of the muscles surrounding the knee joint affects the fatigue characteristics for the quadriceps femoris during testing. Purpose: The purpose of this investigation was to determine whether the peak torque values for the leg extensors (i.e., quadriceps) are influenced by maximally contracting the flexors (i.e., hamstrings) between repetitions. Methods: Eighteen healthy men (mean ± SD age = 23 ± 3 years; body mass = 92.6 ± 12.2 kg) with lower-body strength training experience participated in this study. The subjects were familiarized with the testing procedures prior to data collection. On 2 separate occasions, the subjects performed 50 repeated, maximal concentric isokinetic muscle actions with the left leg extensors. Each muscle action was performed at a velocity of 180°/second through a full 90° range of motion. For one of the trials, the subjects maximally flexed the knee joint using the leg flexors following each full extension in order to bring the dynamometer's lever arm back to the starting position. For the other trial, the subjects relaxed the leg flexors following each maximal leg extension, and an investigator assisted in bringing the lever arm back to the starting position. These 2 trials were performed in a random order. Throughout testing, surface electromyographic signals from the biceps femoris were assessed to ensure compliance with the testing protocol. Percent decline of the leg extensors was calculated as follows: ([initial peak torque − final peak torque]/initial peak torque) × 100. The mean peak torque value was defined as the mean across the 50 repetitions performed throughout each trial. Linear regression was performed on the peak torque values for each trial to determine the linear slope coefficient for the decrease in peak torque (Nm/repetition). Three separate paired samples t-tests were used to examine the data. Results: There was no mean difference between the trials for the leg extensor percent decline in peak torque (hamstrings = 61.4 ± 8.7%, no hamstrings = 62.2 ± 10.6% [p = 0.672, Cohen's d = 0.08]). Similarly, the mean peak torque values did not differ between the trials (hamstrings = 70.4 ± 11.6 Nm, no hamstrings = 71.4 ± 10.5 Nm [p = 0.393, Cohen's d = 0.091]). Finally, there was no mean difference between the trials for the linear slope coefficient for the decline in peak torque (hamstrings = −1.54 ± 0.39 Nm/repetition, no hamstrings = −1.62 ± 0.46 Nm/repetition [p = 0.269, Cohen's d = 0.193]) Conclusions: Inclusion of the musculature responsible for flexing the knee joint did not affect the fatigue-related peak torque values associated with maximal, isokinetic strength testing of the leg extensors. Practical Application: Muscle activity for the flexors does not influence the fatigue levels of the quadriceps femoris during isokinetic strength testing. Therefore, the instructions concerning leg flexion that investigators and practitioners provide to research subjects and/or athletes has little bearing on the peak torque data for the quadriceps femoris muscles.

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8. The Relationship Between Muscle Quantity, Quality, and Rapid Torque Production

J. Rosenberg,1 E. Ryan,1 E. Sobolewski,1 M. Scharville,1 G. King,2 A. Tweedell,1 C. Kleinberg,1 and B. Thompson3

1The University of North Carolina at Chapel Hill; 2Duke's Non-Invasive Vascular Lab; and 3Texas Tech University

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Rapid torque production has been shown to be important for postural stability and rapid motor control tasks. Previous studies have reported that muscle size and quality may independently contribute to muscular strength in older adults. However, we are aware of no previous studies that examined the contribution of these variables to rapid torque production. Purpose: The purpose of the present study was to determine the relationship between rate of torque development (RTD) and muscle cross-sectional area (CSA) and muscle quality. Methods: Thirty-five healthy, recreationally active males (mean ± SD age: 20 ± 2 years; height, 175.6 ± 7.1 cm; mass, 73.4 ± 9.9 kg) volunteered for this investigation. Participants visited the laboratory on 2 separate occasions for familiarization and experimental testing which were separated by 2–7 days and performed at the same time of day (±2 hours). During all ultrasound (US) measurements, participants were examined in the prone position with their leg fully extended and right foot securely attached to a vertical post at a 90° joint angle between the foot and leg. To ensure the probe moved perpendicular to the skin and along the transverse plane during each scan, a custom made probe support composed of high-density foam padding was positioned perpendicular to the longitudinal axis of the leg. Transverse measurements of the medial gastrocnemius (MG) were obtained using a portable B-mode US imaging device. All US imaging analyses were performed using Image-J software. Maximal isometric testing was conducted on a calibrated isokinetic dynamometer with participants seated at a 135° angle between the thigh and torso, their right leg fully extended, and foot secured in a custom steel foot plate. Each participant performed 2–3 maximal voluntary contractions (MVCs) with 2 minutes of recovery between trials. During each MVC, participants were verbally encouraged to plantarflex “as hard and fast as possible” for a total of 3–4 seconds. Peak RTD (RTDpeak) was quantified from the first derivative of the absolute torque-time curve during its initial ascent. A pearson correlation coefficient (r) was used to examine the relationship between RTDpeak and muscle CSA and echo intensity (EI). Furthermore, a stepwise regression analysis was used to determine the contribution of muscle CSA and EI on RTDpeak, with an alpha level of p ≤ 0.05. Results: CSA was positively related (r = 0.41, p = 0.014) and EI was negatively related (r = −0.37, p = 0.031) to RTDpeak. Stepwise regression analyses identified CSA, but not EI, as a significant predictor of RTDpeak (p = 0.014), accounting for 16.8% of the total variance. Conclusions: These findings suggest that among healthy, young males, muscle quantity may be a significantly better predictor of rapid torque production than muscle quality. While muscle quality has been shown to be a significant predictor of muscular strength in older adults independent of muscle size, this may be due to the greater variability in EI among older adults in comparison to the younger population in this study. Practical Application: Future studies may wish to examine the relative contributions of muscle quantity and muscle quality, in addition to other muscle architectural and activation variables that may contribute to explosive strength production.

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9. An Examination of Fatigue Index and Velocity-Related Force Loss for the Forearm Flexors

J. Carr, T. Beck, X. Ye, and N. Wages

University of Oklahoma

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Skeletal muscle is composed of a mixture of 2 main types of muscle fibers: fast-twitch (FT) and slow-twitch (ST). Muscles composed of mostly FT fibers typically demonstrate greater force production, faster contraction times, and a higher fatigue index compared to those with more ST fibers. The greater fatigue index for FT muscles allows for reliable, non-invasive estimates of fiber type composition (% FT vs. ST) with the use of the Thorstensson test. Purpose: The purpose of this study was to examine the relationship between the fatigue index from the Thorstensson test and the velocity-related decrease in peak torque for the forearm flexors. Methods: Thirteen habitually active males (age = 23.3 ± 2.7 years; height = 181.5 ± 5.4 cm; bodyweight = 85.7 ± 13.1 kg) volunteered for this study. The subjects reported to the lab on 3 occasions separated by at least 48 hours. The first visit was a familiarization session with the Loredan isokinetic dynamometer. The second and third visits were randomly ordered and required the subjects to perform either 50 repeated, maximal concentric isokinetic muscle actions of the dominant forearm flexors at a velocity of 180°/second or 6 separate sets of 3 maximal concentric isokinetic muscle actions at randomly ordered velocities of 30, 90, 150, 270, and 330°/second. Bivariate regression was used to calculate the percent declines (PTs) in peak torque from the fatigue test and with increases in velocity. A Pearson correlation was then used to examine the association between the 2 percent declines. An alpha level of 0.05 was used to determine statistical significance for the correlation. Results: There was a significant correlation (r = −0.71, p ≤ 0.05) between the % decline in PT during the fatigue test and the velocity-related % decline in PT. Conclusions: Force output preservation at high contraction velocities was found to be significantly correlated with fatigue index during maximal contractions of the forearm flexors. Practical Application: The relationship between fatigability and the ability to maintain force output at high velocities may provide new insight into non-invasive tests for estimating muscle fiber type composition.

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10. Engaging in Resistance Training Is Associated With Greater Femoral and Spinal Bone Mineral Density in Male Long-Distance Runners

A. Duplanty,1 R. Budnar,1 H. Luk,1 A. Fernandez,1 D. Levitt,1 A. Venable,1 D. Hill,1 N. DiMarco,2 B. McFarlin,1 and J. Vingren1

1University of North TX; and 2Texas Woman's University

*Award Eligible—Doctoral Student Research Award for an outstanding poster abstract presentation.

Introduction: Numerous studies report low bone mineral density (BMD) in male long distance runners. In contrast, resistance training can increase BMD; however, the efficacy of combining resistance training with long distance running has not been elucidated. Purpose: The purpose of this study was to investigate the relation of engaging in resistance training and BMD in long-distance runners. Methods: 14 apparently healthy Caucasian men (mean ± SD; age = 25.6 ± 3.0 years; height = 177.2 ± 4.8 cm, mass = 75.9 ± 9.3 kg) who reported to a) run at least 20 miles per week, b) not participate in any cross training (biking, swimming, etc.), and c) engage in either no resistance training (NRT, n = 6) or at least 1 resistance training session per week (RT, n = 8) over the previous 3 years were recruited. Participants completed medical and exercise training history questionnaires. Body composition including BMD (total body, femoral neck region, femoral greater trochanteric region, femoral total region, and L1-L4 lumbar spine) was assessed using dual energy X-ray absorptiometry (DXA). An independent samples t test was used to compare variables between groups. Results: Age, height, total mass, lean mass, fat mass, body fat %, total body BMD and femoral greater trochanteric region BMD did not differ (p > 0.05) between groups. RT had greater BMD at the femoral neck region (p ≤ 0.05) and lumbar spine (p ≤ 0.05) compared to NRT. There was a trend for greater BMD for total femur (p = 0.058) in RT compared to NRT. Conclusions: Young adult male long-distance runners who reported to participate in resistance training at least once per week had greater BMD in the femoral neck and lumbar spine than their non-resistance trained counterparts. Practical Application: Long-distance runners should perform resistance training at least once per week since this is associated with greater BMD in this population.

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11. Comparison of BIA and DXA for Estimating Body Composition in Collegiate Female Athletes

B. Nickerson,1 R. Snarr,2 P. Bishop,3 H. Williford,4 and M. Esco4

1University of Alabama; 2Arizona State University; 3The University of Alabama; and 4Auburn University at Montgomery

*Award Eligible—Doctoral Student Research Award for an outstanding poster abstract presentation.

Purpose: The purpose of this investigation was to compare hand-to-foot bioelectrical impedance analysis (HF-BIA) to dual-energy x-ray absorptiometry (DXA) for predicting body fat percentage (BF%) and fat-free mass (FFM) in collegiate female athletes. Methods: Forty-four collegiate female athletes (age = 21.1 ± 2.0 years; height = 166.5 ± 6.9 cm; weight = 63.9 ± 10.0 kg) volunteered to participate in the study. Each participant's BF% and FFM was determined via HF-BIA and DXA. The body composition variables between the 2 devices were compared with T-tests, correlation coefficients, standard error of estimate (SEE), and the method of Bland-Altman. Results: The mean (±SD) BF% determined by DXA was 27.7 ± 5.9% and by HF-BIA was 25.8 ± 3.2%, which was significantly different (p ≤ 0.05). HF-BIA significantly correlated with DXA (r = 0.71, p ≤ 0.05) for BF% and yielded a SEE of 4.21%. The limits of agreement (i.e., 95% confidence intervals) for BF% ranged from 10.2% below to 6.4% above the mean difference of −1.9%. The mean FFM (±SD) determined by DXA was 46.2 ± 6.1 kg and by HF-BIA was 47.5 ± 6.0 kg, which was also significantly different (p ≤ 0.05). HF-BIA significantly correlated with DXA (r = 0.89, p < 0.001) for FFM with a SEE of 2.8 kg. The limits of agreement for FFM ranged from 4.0 kg below to 6.6 kg above the mean difference of 1.3 kg. Conclusions: Under these conditions, HF-BIA significantly underestimated BF% and significantly overestimated FFM compared to DXA. In addition, there were large limits of agreements between the 2 devices for BF% and FFM, indicating a wide range in individual differences. Practical Application: Though DXA is a laboratory method utilized to accurately evaluate body composition, it is not convenient for use in large groups of athletes. As a result, field techniques such as HF-BIA are more desirable due to their ease of use and quick administration time. However, based on the results of this study HF-BIA does not appear to serve as a suitable surrogate to DXA for evaluating BF% and FFM in female athletes. Sport practitioners should be aware of the study's results and use caution when interpreting HF-BIA analyses within this population.

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12. The Effects of Various Resistance Training on Bodyweight, Fat Mass, Body Fat Percentage, and Visceral Adipose Tissue in Physically Active Males

J. Carter,1 J. Oliver,2 A. Jagim,3 M. Greenwood,1 J. Parker,1 S. Riechman,1 J. Fluckey,1 S. Crouse,1 and R. Kreider1

1Texas A&M University; 2Texas Christian University; and 3Gannon University

*Award Eligible—Doctoral Student Research Award for an outstanding poster abstract presentation.

Introduction: Visceral adipose tissue (VAT) is linked to a number of obesity related diseases. While traditional (TRD) resistance training (RT) is known to increase lean body mass, strength, and power with a lesser effect on body fat percentage (BF%), the effects on VAT are not well studied. Recent research using cluster sets (CLU) has shown potential in improving power and strength over TRD. CLU allow each repetition to be performed more explosively by breaking TRD sets up into CLU with a brief rest within the set. To what effect these 2 types of RT affect VAT is currently unknown. Purpose: The purpose of this study was to investigate if 12 weeks of CLU or TRD affects body weight (BW), fat mass (FM), BF%, or VAT in healthy males who were previously active. Methods: Twenty-two male subjects (age 25 ± 5 years; height 179.7 ± 5.04 cm; body mass 82.1 ± 10.6 kg; 6.5 ± 4.5 years of training) participated in a structured periodized RT program for 12 weeks. The training involved 4 RT sessions per week divided into 3, 4 week mesocycles. To be included in the study, the subjects had to be between 20–35 years of age, have at least 2 years of RT experience, which included at least 1 RT session per week that targeted both the upper and lower body, and not ingest any ergogenic supplement excluding supplemental protein or multivitamins for the previous 6 weeks. The subjects were equally and randomly divided into the CLU (n = 11) and TRD (n = 11) based on their baseline characteristics. During the training, the subjects had their body composition analyzed using a DEXA at the Exercise and Sports Nutrition Laboratory at 0, 4, 8, and 12 weeks of training. Results: MANOVA revealed a significant time (p < 0.001) and group x time (p < 0.051) effect. There was a significant training effect for change in BW (CLU 1.13 ± 1.67, TRD 2.94 ± 1.32 kg, p = 0.011) between the interventions following 12 weeks of RT. However, there was no significant training effect between the interventions for change in total BF (CLU 0.60 ± 1.02, TRD 1.04 ± 1.76 kg, p = 0.47), fat free mass (CLU 1.01 ± 1.98, TRD 2.19 ± 2.09 kg, p = 0.19), or BF% (CLU 0.56 ± 1.38, TRD 0.75 ± 2.26%, p = 0.82) after 12 weeks of RT. However, CLU resulted in a significantly greater loss for VAT mass (CLU -2.00 ± 10.01, TRD 42.72 ± 49.25 g, p = 0.008), VAT volume (CLU -2.09 ± 10.40, TRD 46.27 ± 53.34 cm3, p = 0.008), and VAT area (CLU −0.42 ± 2.05, 8.86 ± 10.26 cm2, p = 0.008) compared to TRD. Conclusions: This study showed that CLU may be beneficial in reducing VAT mass, VAT volume, and VAT area compared to TRD. Practical Application: Very little is known about RT in regards to VAT changes. Furthermore, less is known about differing types of RT in regards to VAT alterations. This study showed that CLU may be beneficial in reducing VAT mass, VAT volume, and VAT area compared to TRD. This may be just 1 additional benefit for athletes engaging in CLU. However, further research is needed in this area to draw sound conclusions. Acknowledgments: This study was funded by the National Strength and Conditioning Association Doctoral Research Grant.

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13. Muscle Characteristics and Body Composition Across Player Position in NCAA Division I Football Players

M. Melvin,1 A. Smith-Ryan, 2 H. Wingfield,1 E. Roelofs,2 and E. Trexler2

1University of North Carolina at Chapel Hill; and 2The University of North Carolina at Chapel Hill

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Body composition and muscle characteristics of NCAA Division I football players have the potential to impact athletic performance. Evaluating baseline differences across position may be useful to reference if a player suffers an injury, gains or losses weight, or declines in performance. Muscle characteristics, as determined by muscle cross sectional area (mCSA) and echo intensity (EI), measured with ultrasound (US), may have utility for the strength and conditioning professional. Purpose: The purpose of this study was to investigate mCSA and EI of the vastus lateralis (VL) and body composition of NCAA Division I football players. Methods: Sixty-nine Divison I football players (Mean ± SD; Age: 20.0 ± 1.1 years; Height: 186.2 ± 7.0 cm; Body mass: 106.3 ± 21.1 kg; %fat: 17.8 ± 4.6%) volunteered to participate in this study. Subjects were stratified by player position: defensive linemen (DL), offensive linemen (OL), quarterbacks (QB), running backs (RB), wide receivers (WR), tight ends (TE), linebackers (LB), defensive backs (DB), and kickers/punters (KP). Players were also stratified by race, year classification, and starter status. Muscle CSA of the VL was determined from a panoramic scan of the VL using a GE logiq-e B-mode US. The US probe was held perpendicular to the tissue and swept across the skin at equal pressure from the lateral VL border to medial fascia separation. Echo intensity was determined from the panoramic scan by grayscale analysis using Image-J software. Body composition measures including fat mass (FM), lean mass (LM), and %fat were determined using dual-energy x-ray absorptiometry (DXA). One-way ANOVAs were used to evaluate differences in mCSA, EI, %fat, LM, and FM between position, race, year and starter status. Results: For mCSA, DL (46.7 ± 4.2 cm2) had significantly greater (p ≤ 0.05) CSA than WR, LB, DB, PK, and RB (Δ 5.4–14.4 cm2). Muscle CSA for OL (42.0 ± 5.5 cm2) was only significantly greater (p ≤ 0.05) than WR (Δ = 9.7 cm2). For %fat, LM and FM there were no significant differences between OL (22.3 ± 2.3%, 96.6 ± 6.8 kg, 29.9 ± 9.4 kg) and DL (24.4 ± 2.2%, 96.2 ± 4.8 kg, 29.1 ± 4.8 kg). However, OL and DL had significantly greater: %fat than WR, LB, DB, PK, and RB (Δ = 7.4–10.5%; p ≤ 0.05); greater LM than all other positions (Δ = 12.4–28.2 kg, p ≤ 0.05); as well as more FM than QB, WR, LB, DB, PK, and RB (Δ = 12.5–17.5 kg, p ≤ 0.05). There were no muscle or body composition differences for race, year, or starter status. Conclusions: Measures of mCSA, %fat, LM, and FM were found to be significantly different across position, likely due to the differences in position-specific tasks. However, no differences between positions were observed for EI measures, which may indicate competitive athletes have increased muscle quality regardless of body size and composition differences. Practical Application: Ultrasound mCSA and DXA measures may provide beneficial information for athletes, strength coaches, and athletic trainers. When returning to play from an injury, DXA and US measures may be beneficial for quantifying muscle imbalances, particularly between each arm and leg, as well as integrity of the tissue. Knowledge of regional fat distribution, muscle quality, and muscle imbalances may also improve the design of resistance exercise prescriptions targeting weight loss or gain.

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14. Effect of Inorganic Nitrate Consumption on Oxygen Consumption During Submaximal Exercise in Trained and Untrained Runners

C. Carriker, T. VanDusseldorp, N. Beltz, K. Johnson, N. Cole, J. McCormick, R. Vaughan, and A. Gibson

University of New Mexico

*Award Eligible—Doctoral Student Research Award for an outstanding poster abstract presentation.

Purpose: The purpose of this study is to investigate the submaximal metabolic response initiated after acute inorganic nitrate consumption in trained and untrained runners during 5 minute exercise bouts of varying intensities. Methods: Five untrained (42.44 ± 3.19 ml/kg/min) and 6 trained (60.09 ± 4.63 ml/kg/min) males (age 24 ± 4 years), gave informed consent for this IRB approved study. Participants were classified as trained or untrained (>85% or <65% age and gender norms; respectively) and completed 3 experimental trials (T1, T2, T3). T1 included baseline demographics and maximal aerobic capacity (

) via treadmill running. In a randomized, double-blind, placebo-controlled, crossover fashion, subjects were initially assigned to a placebo (PL) or inorganic nitrate rich (NR) group. Following T1, subjects underwent a 4 days washout minimizing consumption of nitrate rich foods. Participants then completed a 4 days loading protocol during which they consumed ∼4.2 mmol nitrate/day. Participants were asked to minimize the consumption of nitrate rich foods. The final dose was administered 2.5 hours prior to T2. Exercise during T2 consisted of 5 bouts of 5 minutes submaximal cycling at 45, 60, 70, 80 and 85%

. A second 6 days washout and 4 days loading, was observed prior to T3. T3 began 2.5 hours after the subject consumed the final NR or PL beverage. T3 consisted of identical procedures from T2.

was assessed to determine whether NR reduced oxygen cost, rating of perceived exertion (RPE), and heart rate (HR). Using a repeated measures ANOVA, main and interaction effects were determined for each beverage and between training status. Significance was determined at p ≤ 0.05. Results: Oxygen cost was reduced following nitrate consumption compared with placebo for untrained participants (p ≤ 0.05) at the lowest 2 intensities (45 and 60%

). There was no difference in oxygen cost for trained participants (p > 0.411 all intensities). Beverage consumption conferred no difference in HR across the 5 submaximal intensities for either group. Rating of perceived exertion remained similar throughout exercise at all intensities regardless of training status with a single exception for untrained participants at 70%

(p = 0.046). Conclusions: Oxygen cost was reduced for untrained participants during the lowest 2 intensities (45 and 60%

) while RPE for untrained was only reduced at 70%

. Trained participants did not exhibit any benefit following ingestion of the beverage rich in dietary nitrate. Heart rate was not changed for either group at any intensity. Practical Applications: Untrained participants may experience a reduction in oxygen cost during low to moderate intensity (<60%

) exercise after consumption of a beverage high in dietary nitrate. While RPE was not reduced over all workloads for trained participants, untrained participants perceived their level of exertion as being easier while exercising at 70%

following NR beverage consumption. The implications of these findings suggest untrained participants may experience benefits from NR beverages as compared to individuals who have a higher fitness level as indicated by

. Acknowledgments: Funding Received from NSCA's GNC Nutritional Research Grant 2013.

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15. Forearm Skin Blood Flow Responses to Kinesiology Tape: A Pilot Study

R. Herron, A. Collins, S. Carter, J. Mitchell, and P. Bishop

The University of Alabama

*Award Eligible—Doctoral Student Research Award for an outstanding poster abstract presentation.

Purpose: In recent years the use of kinesiology tape (KT) has increased in competitive sports. Previous research has suggested a reduction in pain and inflammation with KT use. The purpose of this investigation was to examine forearm skin blood flow responses with the application of KT. Methods: Three healthy participants (n = 3 males, age 22 ± 4 years) had 2 skin blood flow sites assessed simultaneously; tape (KT) vs. control (CON). Participants rested supine as KT was applied to the brachioradialis in accordance with manufacturer guidelines. A laser Doppler flowmetry probe (LDF) integrated with a local skin heater was positioned over the KT and CON sites on the dominant forearm. A small aperture in the KT allowed for direct measure of the blood flow. Skin blood flow (in arbitrary units; au) and blood pressure were assessed over a 5-minute baseline period during which local skin temperature was clamped at 34 °C. Local heating was increased at a rate of 0.2 °C·10 s−1 to a final temperature of 42 °C to elicit maximal cutaneous vasodilation and held for 30 minutes. Blood pressure was measured every 10 minutes via automated oscillometry. Mean arterial pressure (MAP) was used to calculate cutaneous vascular conductance (CVC; LDF/MAP). Results: An independent samples t-test found no difference in skin blood flow at baseline or max as expressed in %ΔCVC (Baseline p = 0.79, KT = 0.386 ± 0.080 au/mm Hg vs. CON = 0.353 ± 0.189 au/mm Hg; Max%Δ p = 0.56, KT = 351 ± 64% vs. CON%Δ = 448 ± 253%). Conclusions: KT did not affect baseline or maximal skin blood flow as indexed by LDF. Practical Application: One of the proposed mechanisms through which KT is able to alleviate pain and inflammation is through increased blood flow at application sites. Prior claims have suggested that KT tape can lift and deform the skin allowing for increased circulation. Theoretically, better circulation could benefit venous and lymphatic return, and in turn, reduce pain receptor stimulation. Within the framework of this design, these data do not support increased skin blood flow through which KT is hypothesized to attenuate pain and inflammation. However, further research is warranted due to the heterogeneity of the skin found in this pilot study.

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16. Safety of 28 Days of Creatine Nitrate Supplementation

J. Joy

University of Tampa/MusclePharm Corp

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Creatine monohydrate was first discovered as an ergogenic aid over 30 years ago when it was observed to increase myosin biosynthesis. Since, it has become a very popular ergogenic aid for its capabilities to increase strength, reduce fatigue, and increase lean mass. Thus, a great number of athletes and recreational fitness enthusiasts have reported consuming creatine. The safety of creatine monohydrate has previously been confirmed. However with each novel form of creatine that emerges, its safety must be verified. Purpose: Therefore, the purpose of this study was to examine the safety of a novel form of creatine, creatine nitrate (CN), over a 28 day period. Methods 27 college aged males and females participated in this study. Subjects were equally and randomly assigned to consume either 1 g (n = 14) or 2 g (n = 13) of CN daily. Blood draws for full safety panels were conducted by a trained phlebotomist prior to and at the conclusion of the 28-day supplementation period. Dependent samples T-tests were used to determine within condition differences. Results: Within condition differences existed for RBC, MCV, MCHC, RDW, % monocytes, serum glucose, BUN, serum creatinine, BUN:creatinine, serum calcium, total serum protein, serum albumin, AST, and ALT in the 1 g condition (p ≤ 0.05). Within condition differences existed for MCV, MCHC, % monocytes, absolute lymphocytes, serum creatinine, eGFR, BUN:creatinine, CO2, and total bilirubin in the 2 g condition (p ≤ 0.05). In the 1 g condition, RBC, MCHC, RDW, % monocytes, serum glucose, BUN, BUN:creatinine, serum calcium, serum albumin, and total serum protein increased, yet MCV, creatinine, AST, and ALT decreased. In the 2 g condition, MCHC, % monocytes, eGFR, and BUN:creatinine increased, yet MCV, absolute lymphocytes, creatinine, CO2, and total bilirubin decreased. Common increases for MCHC, % monocytes, and BUN:creatinine were observed between conditions, and common decreases for MCV and creatinine were observed between conditions. Conclusion: Surprisingly, creatinine decreased in both conditions, which explains the increase in BUN:creatinine. The increase in MCHC and decrease in MCV could be attributed to the nitrate portion of CN, which has been known to augment hemodynamics, but it is more likely that changes in MCHC and MCV were due to variability, as hematocrit, hemoglobin, and RBC did not have the same magnitude of change for both conditions. Despite significant changes in these hematological measures with CN supplementation, all values remained within normal ranges. Therefore, CN appears to be safe in both 1 g and 2 g servings daily for 28 days. Practical Applications: This supplement will theoretically aid performance in short duration, high intensity exercise, and this study demonstrates it is safe for consumption of up to 2 g daily in healthy men and women. Acknowledgments: This study was supported by MusclePharm Corp. The authors claim no conflict of interest.

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17. Effects of Chocolate Goat and Cow Milk on Force Recovery and Endocrine Responses after Back Squat Exercise

N. LeBlanc,1 D. Bellar,1 K. Moody,1 K. Murphy,1 G. Buquet,1 and L. Judge2

1University of Louisiana at Lafayette; and 2Ball State University/School of PE, Sport, and Exercise Science, Muncie, IN

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Purpose: This investigation examined the effects of chocolate milk from both goats and cows on endocrine responses and isometric mid thigh pull performance post back squat exercise. Methods: Participants included 12 college aged males (mean ± SD; Age 22.8 ± 2.4 years; height 178.9 ± 8.8 cm; weight 85.2 ± 10.7 kg; body fat 14.5 ± 4.8%, Back Squat 1RM: 139.6 ± 17.3 kg) with greater than 1 year experience with the back squat exercise. The participants reported to the lab on 4 occasions. The first visit included anthropometric measurements, determination of the back squat 1RM and familiarization with the isometric mid thigh pull assessment. The subsequent 3 visits included 5 sets of 8 repetitions of the back squat exercise at 80% of the participants previously determined 1RM. During these 3 trials, the participants performed an isometric mid-thigh pull. Saliva samples were collected prior to, immediately after, 1 hour and 2 hours post exercise to allow for hormone quantification. The back squat exercise was conducted to a parallel depth (visual markers used), and the cadence was controlled with a metronome set at 40 beats per minute. In this manner, the work performed during each trial was held constant. During the 3 exercise trials, a treatment was administered at the conclusion of exercise in a random double blind fashion. The treatments included low fat chocolate goats milk (355 ml, 225 kcal), low fat chocolate cow's milk (355 ml, 225 kcal) and a control (water 355 ml, 0 kcal). At the conclusion of all trials, hormone quantification for dehydroepiandrosterone (DHEA) testosterone (TEST) and cortisol (CORT) were undertaken with commercial ELISA kits. Results: Repeated measures Anova's were used to examine the changes in mid-thigh pull performance and hormone levels by time (pre, post, 1 hour, 2 hours). Analysis of mid thigh pull data demonstrated a significant main effect for time (F = 2.94, p = 0.048) with reductions in performance at the post and 60 minutes times, but no significant main or interaction effects for treatment (p > 0.05). Analysis for DHEA, TEST, CORT similarly revealed significant main effects for time (F > 8.3, p ≤ 0.001) but no significant main or interaction effects for treatment. Conclusions: Based upon these data, it does not appear that a single dose of either chocolate goat's or cow's milk is sufficient to alter post-exercise isometric strength or endocrine response. Practical Application: Practitioners need to be aware of the most effective solutions for post-exercise nutrition to help promote recovery. The present study does not suggest that a 355 ml dose of low fat chocolate dairy product is valuable in promoting an anabolic physiological state. Acknowledgments: The present investigation was funded by a grant from Mt Capra Wholefood Nutritionals.

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18. Effects of Arachidonic Acid Supplementation on Skeletal Muscle Mass, Strength, and Power

J. Ormes,1 R. Lowery,1 J. Silva,2 J. Rauch,2 S. Weiner,1 S. McCleary,2 J. Georges,1 K. Shields,1 M. Sharp,1 J. Joy,1 and J. Wilson1

1University of Tampa Human Performance Lab; and 2University of Tampa

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Arachidonic acid (ARA) is a long-chain omega-6 polyunsaturated fatty acid that can be integrated into membrane phospholipids and it is the primary substrate for COX-2-mediated biosynthesis of prostaglandins. Previous research found that ARA enhances power in strength-trained college-aged males. However, co-adminsitering 90 g/d of supplemental protein may have obscured the potential hypertrophic effects of ARA supplementation. Purpose: Therefore, the purpose of this study was to investigate the effects of 8 weeks of ARA supplementation in resistance trained individuals during a periodized resistance training program on skeletal muscle hypertrophy, body composition, strength, and power relative to a placebo-matched control. Methods: Thirty recreationally-trained males aged 20.4 ± 2.1 years with a respective average leg press and bench press of 231.5 ± 55.6 kg and 103.9 ± 26.8 kg, respectively, and a minimum of 1 year of resistance training experience were recruited for the study. All subjects participated in an 8-week, 3-day per week, periodized, resistance-training program that was split-focused on multi-joint movements such as leg press, bench press, and bent-over rows. Ultrasonography measured muscle thickness of the quadriceps, dual-energy X-ray absorptiometry (DEXA) determined lean body mass, power, and strength of the bench press and leg press were determined at weeks 0, and 8 of the study. Results: There were time, and group-by-time interactions for LBM (p ≤ 0.05) in which LBM increased from pre (ARA 57.7 ± 4.8 kg; Placebo 57.6 ± 5.0 kg to post (ARA 57.8 ± 5.6 kg; Placebo 59.3 ± 5.0 kg) only in ARA group, but not the placebo. Delta change of LBM was significantly greater in the ARA group (1.62 ± 0.01 kg) than the placebo (0.09 ± 0.7) (p ≤ 0.05). The Delta change for muscle thickness was greater in the ARA group (0.47 ± 0.08 cm) than the placebo (0.25 ± 0.04 cm) (p ≤ 0.05). There was a time, and group by time interaction for Wingate power, in which power increased to a greater extent in ARA (723.01 ± 104.53 W to 800.66 ± 112.60 W) than the placebo (738.75 ± 129.76 to 766.51 ± 136.52 W). Delta change for total strength (bench press + leg press) was greater in the ARA group (109.92 ± 33.25) than the placebo (75.78 ± 12.41). Conclusions: These results suggest that this ARA can positively augment adaptations in strength, and skeletal muscle hypertrophy in resistance-trained men. Practical Application: Athletes and everyday individuals looking to maximize their body composition, strength, and power could use ARA as an ergogenic aid.

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19. Phosphatidic Acid Supplementation Does Not Alter Body Composition or Strength in Sedentary, Middle Aged Men and Women

M. Sharp,1 J. Joy,1 R. Lowery,1 J. Ormes,1 S. McCleary,2 K. Shields,1 S. Weiner,1 J. Rauch,2 J. Silva,2 J. Georges,1 and J. Wilson1

1University of Tampa Human Performance Lab; and 2University of Tampa

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Phosphatidic Acid (PA) has recently emerged as a potent signaling molecule in the mammalian target of rapamycin (mTOR) anabolic pathway. PA consumed as an ergogenic aid coupled with resistance training has shown to be beneficial in increasing muscle hypertrophy. However, the effects of PA in a sedentary, middle-aged model are yet to be investigated. Purpose: To investigate the effects of 8 weeks of PA supplementation on body composition and strength in sedentary men and women. Methods: 15 male and 15 female participants aged 43.5 ± 3.8 years participated in this study. Subjects were given either 750 mg daily of PA or an equal volume, visually identical placebo in a double blind manner for 8 weeks. Subjects were instructed to maintain their diet and activity levels, and each was monitored for the duration of the study. Body composition was analyzed by DEXA along with ultrasound determined cross sectional area (CSA) of the rectus femoris. Muscular performance was assessed via handgrip and knee extensor isometric dynamometer tests. All measures were taken prior to and at the conclusion of the supplementation period. Results: No differences existed at baseline for diet, activity, or any dependent variables. Diet and activity levels remained constant throughout the study. No group x time interactions were present for body fat percentage, fat mass, lean body mass, CSA, handgrip strength, or knee extensor strength for men or women. Conclusions: Phosphatidic Acid does not appear to be a potent stimulus for lean mass accretion in sedentary, aging populations. Practical Application: PA supplementation should be used in combination with a resistance-training program in order to elicit its ergogenic potential.

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20. Reliability of a Novel Test of Upper Body Isometric Strength

M. Breaux,1 D. Bellar,1 L. Marcus,1 and L. Judge2

1University of Louisiana at Lafayette; and 2Ball State University/School of PE, Sport, and Exercise Science, Muncie, IN

*Award Eligible—Undergraduate Student Research Award for an outstanding poster abstract presentation.

Purpose: This investigation examined the association of a novel test of upper body isometric strength against a 1RM bench press measurement. Methods: Thirty-two college age adults (n = 18 female, n = 14 male; mean ± SD; Age 22.8 ± 2.9 years; height 171.5 ± 11.2 cm; weight 71.4 ± 15.7 kg; body fat 23.6 ± 5.0%) volunteered for the present investigation. The participants reported to the lab on 2 occasions. The first visit included anthropometric measurements and familiarization with both the upper body isometric test. The final visit consisted of 3 attempts of the novel upper body isometric assessment separated by 5 minutes of recovery. Grip width was held constant at 150% of biacromial width for both the bench press and isometric test. For the isometric test, participants were positioned in such a manner to create 90 degrees of elbow flexion, a flat back and 150% of biacromial width in a “push-up” style position while tethered (stainless steel chain) to a load cell (high frequency) anchored to the ground. The participants were instructed to push-up against the chain as hard as possible, and were not allowed to start with any slack in the chain. The attempt was concluded when a noticeable decline in force production was observed (50N). Generally, each trial lasted no more than 5 seconds. The peak isometric force was recorded for each of 3 attempts. Results: Repeated measures Anova analysis did not reveal a main effect for attempt (F = 2.09, p = 0.142). Mean values for Attempt 1 (400.8 ± 225.1 N) and Attempt 2 (403.3 ± 218.9) were very similar. Though non-significant, there appeared to be trend for reduced force production in the third attempt (381.1 ± 222.3 N). Conclusions: Results from this study suggest that the novel isometric upper body strength assessment is reliable, and it is likely that only 2 attempts are necessary to elicit peak isometric force. Practical Application: The study reveals that a simple and effective test is reliable and could prove to be a valuable tool for the strength and conditioning professional.

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21. Effects of Traditional vs. Alternating Whole-Body Strength Training on Average Power and REPS to Failure

A. Ciccone,1 R. Hafenstine,2 A. Cho,3 L. Brown,3 J. Coburn,3 and A. Galpin3

1California State University Fullerton; 2Fullerton College; and 3California State University, Fullerton

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Traditional strength training utilizes 2- to 5-minute inter-set rest intervals, which can result in long workouts. Although performing dissimilar exercises during rest intervals can minimize workout duration, these workouts may affect workout performance. Purpose: To compare the effects of traditional (TS) vs. alternating (AS) whole body strength training on squat (SQ) average power (AP) and repetitions to failure. Methods: Twenty healthy resistance-trained men (age = 24 ± 2 years, mass = 84.6 ± 10.0 kg, height = 177.7 ± 7 cm, SQ 1RM = 151 ± 21 kg, bench press (BPR) 1RM = 111 ± 15 kg, bench pull (BPU) 1RM = 71 ± 9 kg) completed 2 workouts using 80% 1RM. One workout consisted of 4 sets of squats on a force plate with a velocity transducer attached to the barbell, with 3-minutes passive rest between sets. Another workout consisted of SQ, BPR, and BPU exercises in an alternating manner with 50-seconds rest between sets. For both workouts, sets 1–3 were performed for 4 repetitions, while the fourth SQ set was performed to concentric failure. Total number of completed repetitions of the fourth SQ set was recorded. Also, average power was calculated for each repetition and averaged for each set and volume-equated for set 4. Results: AP was analyzed using a 2 × 4 (condition x set) repeated measures ANOVA, which revealed there was no significant interaction (p > 0.05). There was a main effect for workout condition (p ≤ 0.05) where TS (989 ± 183) was greater than AS (937 ± 176). There was also a main effect for set (p ≤ 0.05) where set 1 (1035 ± 208) was greater than sets 2 (989 ± 172 W), 3 (960 ± 175 W), and 4 (867 ± 163) and set 2 was greater than sets 3 & 4 and set 3 was greater than set 4. During the TS condition, subjects performed significantly more repetitions to failure (7.5 ± 2.3) when compared to the AS condition (6.3 ± 2.2). Conclusions: These data suggest that the addition of upper-body multi-joint exercises during SQ rest intervals can decrease lower-body AP and repetitions to failure. Practical Application: Individuals can decrease total strength workout duration by performing with added upper-body multi-joint exercises during squat rest intervals for the first 3 sets of squats without impairing squat AP. However, added upper-body multi-joint exercises during lower-body rest intervals can impair AP over 4 sets and decrease SQ reps to failure.

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22. Differences in Time Under Tension During the Back Squat Using Traditional vs. Cluster Set Configurations

S. Jenke,1 A. Kreutzer,1 M. Jones,2 M. Phillips,1 J. Mitchell,1 and J. Oliver1

1Texas Christian University; and 2George Mason University

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Greater gains in power with similar gains in lean mass have been reported following 12-weeks of hypertrophy training using cluster (CLU) compared to traditional (TRD) set configurations at the same total volume load. Time-under-tension (TUT) has been shown to maximize hypertrophic adaptations. However, whether there is a difference in TUT between CLU and TRD is currently unknown. Purpose: The current study examined the effect of TRD vs. CLU on differences in time under tension (TUT) responses during the concentric (CON) and eccentric (ECC) portions of the back squat (BS) exercise. Additionally, the perceptual responses to the different set configurations were investigated using Borg's ratings of perceived exertion (RPE) scale. Methods: Nine resistance trained males (mean ± SD; 25.7 ± 4.1 years; 177.7 ± 7.8 cm; 83.2 ± 8.1 kg; 15.5 ± 5.0% body fat; 5.7 ± 2.0 years training) had their body composition determined (dual x-ray absorptiometry) followed by determination of one-repetition maximum (1RM) BS (147.2 ± 18.8 kg; BS:body mass 1.8 ± 0.3) prior to the performance of 4 sets of 10 repetitions (reps) with 120 seconds (s) rest (TS) and 4 × (2 × 5 reps) with 30 seconds rest between clusters, and 90 seconds between sets, assigned randomly. Both trials were performed with 70% 1RM BS and were separated by 7 days. CON, ECC, and total (TOT) TUT were collected at 1000 Hz. Participants were instructed to perform every rep “as explosively as possible.” If participants rested for more than 2 seconds between reps, or were unable to complete a rep, resistance was lowered by 13.6 kg. A 2 (CONDITION) × 4 (SET) × 10 (REP) repeated measures ANOVA was used to analyze differences (p ≤ 0.05; mean ± SE). Results: A significant effect of SET was observed for CON (p = 0.001), ECC (p = 0.002), and TOT (p = 0.001) TUT. TOT TUT increased from SET1 (1.856 ± 0.75 s) to SET4 (2.120 ± 0.111 s; p = 0.001) with a similar pattern observed in CON and ECC. A CONDITION X REP effect was also observed for CON (p = 0.001), ECC (p = 0.003), and TOT (p = 0.001) TUT. TOT TUT was greater for every rep in TRD when averaged over SET. When averaged over sets the greatest increase in TOT TUT for TRD was observed in later reps (REP 7, 2.219 ± 0.154 s; REP8, 2.208 ± 0.133 s; REP9, 2.176 ± 0.114 s; REP10, 2.359 ± 0.141 s), while significantly greater TOT TUT was observed only in later reps of each cluster (REP5, 1.953 ± 0.81 s; REP8, 1.867 ± 0.094 s; REP9, 1.942 ± 0.104 s; REP10, 2.106 ± 0.115 s) in CLU. A similar pattern was observed in CON TUT. There was minimal change in ECC TUT during both conditions. A significant effect of CONDITION (p = 0.011) and SET (p = 0.001) in RPE was observed. RPE increased over each SET averaged over CONDITION (SET1, 12.5 ± 0.6; SET2, 14.3 ± 0.6; SET3, 16.3 ± 0.7; SET4, 17.5 ± 0.7), with TRD having a higher overall RPE (15.6 ± 0.6) compared to CLU (14.7 ± 0.7; p = 0.011). Conclusions: These data suggest differences in TOT TUT between TRD and CLU are a result of the CON portion of the lift. Further, RPE may be related to CON TUT. Practical Application: For athletes involved in sports requiring a high power output, CLU may best be utilized during hypertrophic training to minimize the decrease in CON TUT, which allows similar gains in lean mass compared to TRD but greater power adaptations. Acknowledgments: This work was supported in part by a grant from the TCU Research and Creative Activities Fund.

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23. The Usefulness of Average Velocity of Opening Deadlift Attempts in Open and Collegiate Powerlifters During Competition as a Predictor of Performance

A. Klemp,1 C. Dolan,1 J. Quiles,1 K. Schau,1 B. Esgro,1 E. Jo,2 and M. Zourdos1

1Florida Atlantic University; and 2California State University Pomona

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Success in the sport of powerlifting is dependent upon the completion of near maximum intensity loads in the squat, bench press, and deadlift exercises. Furthermore, recent literature has suggested that experienced lifters are more efficient (i.e., can achieve slower velocities) at higher intensities compared to less experienced or novice lifters. Therefore, appropriate attempt selection during a competitive powerlifting meet is essential to achieve optimal performance. However, research has not yet examined how velocity of attempts during a meet may impact or predict the velocity of subsequent attempts and overall powerlifting performance. Purpose: To investigate if any correlation exists between the average velocity of the first attempt in the deadlift and the successful completion of subsequent attempts. Additionally, we compared the average velocity of first attempts, in the deadlift between collegiate (CPL) and open powerlifters (OPL). Methods: Thirty-seven competitive powerlifters (weight.: 83.1 ± 24.1 kg.; height: 174 ± 7.1 cm; body fat: 13.3 ± 6.1%) competed in either a Collegiate (n = 26) or Open (n = 11) division during the 10th USA Powerlifting (USAPL) Florida Collegiate State Championships and Southeastern USA Regional Powerlifting Championships. Each competitor had their load (kg) and average and peak velocities (m/s) measured and recorded during the competition via a Tendo unit placed on the barbell for all 3 attempts in the deadlift. Paired t-tests were utilized to compare average and peak velocity between groups and Spearman correlations were used to examine if any correlation between average velocity of the first attempt and successful second and third attempts existed. Significance was set at p ≤ 0.05. Results: CPL exhibited significantly (p ≤ 0.05) faster first attempt average velocities (0.45 ± 0.9 m/s) compared to OPL (0.37 ± 0.65 m/s). However, across all 37 powerlifters no correlation existed between average velocity of the first attempt and the successful completion of subsequent attempts (p = 0.12, R = 0.26). Conclusions: The findings demonstrate that CPL first attempts in the deadlift are significantly faster than OPL. This may signify that CPL are not as experienced and, therefore, not as efficient in performing the deadlift; as evidenced by recording faster velocities at similar relative intensities compared to OPL. Additionally, no correlation was observed between first attempt average velocity and the successful completion of subsequent attempts. Practical Application: To our knowledge this is the first study to examine deadlift velocities of powerlifters during a sanctioned competition. Based on these results it appears that less experienced powerlifters are less efficient than more experienced powerlifters and therefore, should select a first attempt deadlift load that allows for a faster velocity in comparison to a more experienced powerlifter, in an effort to optimize performance. Acknowledgments: The authors would like to thank Dr. Robert Keller and the USAPL for the opportunity to collect data during competition.

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24 Velocity Drives Power Output During the Back Squat Using Cluster Set and Traditional Configurations

A. Kreutzer,1 S. Jenke,1 M. Jones,2 M. Phillips,1 J. Mitchell,1 and J. Oliver1

1Texas Christian University; and 2George Mason University

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Cluster sets (CS) result in greater power output during a single exercise bout when compared to traditional set configurations (TS). Further, greater gains in power have been reported when incorporating cluster sets (CS) during hypertrophic training due to the ability to work at a greater average power output. To what extent force and velocity contribute to the overall greater power output at hypertrophic intensities is unknown. Purpose: The purpose of this study was to compare the effects of CS and TS on the kinetic and kinematic profile during hypertrophic back squat exercise (BS). Methods: Nine resistance trained men (mean ± SD; 25.7 ± 4.1 years; 177.7 ± 7.8 cm; 83.2 ± 8.1 kg; 15.5 ± 5.0% body fat; 5.7 ± 2.0 years training) participated in this repeated measures crossover study consisting of body composition determination (dual x-ray absorptiometry), one-repetition maximum (1RM) BS (147.2 ± 18.8 kg; BS:body mass 1.8 ± 0.3), and the performance of TS (4 sets x 10 REPs at 70% 1RM with 120 seconds rest) and CS (4 × (2 × 5) at 70% 1RM with 30 seconds between clusters and 90 seconds between sets). Seven days separated trials. Kinematic and kinetic measurements were sampled at 1000 Hz via force plate and 2 linear position transducers. Participants were instructed to perform every rep “as explosively as possible.” If participants paused for more than 2 seconds between reps, or were unable to complete a rep, resistance was lowered by 13.6 kg. Results: A significant SET (p = 0.002) and a CONDITION × REP interaction (p = 0.002) were observed in average power (Pa). Pa decreased significantly (p = 0.003) in both groups from SET1 to SET4 (1532 ± 107 W to 1297 ± 131 W). CS resulted in significantly greater Pa across all reps averaged over sets with exception of REP5 (p = 0.264). The greatest differences in Pa when comparing CS with TS were observed in latter reps (REP6: 162 ± 49; REP7: 234 ± 42; REP8: 194 ± 31; REP9: 157 ± 29; REP10: 156 ± 25 W) when compared with TS. A significant SET (p < 0.001) effect and CONDITION x REP interaction (p = 0.001) were observed for average velocity (Va). Va decreased significantly (p = 0.001) in both groups from SET1 to SET4 (0.828 ± 0.029 to 0.709 ± 0.041 m·s−1). While CS resulted in significantly greater Va across all REPS averaged over sets with exception of REP5 (p = 0.114). The greatest differences in Va when comparing CS with TS were observed in later REPS (REP6: 0.828 ± 0.029, REP7: 0.120 ± 0.020, REP8: 0.097 ± 0.016, REP9: 0.081 ± 0.017, REP10: 0.074 ± 0.014 m·s−1). Average force (Fa) was significantly greater (p = 0.009) in CS (1858.5 ± 57.8 N) when compared with TS (1846.8 ± 58.4 N). Fa was significantly lower in SET 4 (1843 ± 60 N) compared to SET2 (1857.1 ± 57.3 N; p = 0.035), SET3 (1853.9 ± 57.4 N; p = 0.032), and SET1 (1856.8 ± 57.2 N; p = 0.051). Conclusions: While Va and Pa decreased from REP1 to REP10, Fa did not change within sets. This suggests that Va is the driving factor for decrements in power during CS and TS. Further, greater Pa and Fa during CS when compared with TS across all sets - especially in later REPS - suggests that CS allow for greater maintenance of both of these variables. Practical Application: The present study suggests that maintaining velocity is the most important factor in optimizing power output. Further, the present results confirm that CS provide a valuable tool to increase Pa and Va during hypertrophy training cycles. Acknowledgments: This work was supported in part by a grant from the TCU Research and Creative Activities Fund.

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25. A Comparison of Three Methods of Assessing the Lower Body Stretch-Shortening Cycle Utilization of Athletes

T. Suchomel, C. Sole, and M. Stone

East Tennessee State University

*Award Eligible—Doctoral Student Research Award for an outstanding poster abstract presentation.

Purpose: The purpose of study was to compare 3 methods of assessing the lower body stretch-shortening cycle (SSC) use of athletes. Methods: Eighty-six NCAA Division I athletes performed unloaded countermovement (CMJ) and squat jumps (SJ) on a force plate. Jump height (JH) and peak power (PP) were calculated for both the CMJ and SJ. Three methods of assessing lower body stretch-shortening cycle use were calculated. The measures included: Pre-Stretch Augmentation Percentage (PSAP) calculated as ((CMJ–SJ)/SJ) × 100, Reactive Strength (RS) calculated as CMJ–SJ, and Reactive Strength Index-Modified (RSImod) calculated as CMJ height/time to takeoff. A series of one-way repeated measures ANOVA were used to compare differences in PSAP and RS for JH and PP and RSImod between sport teams. Results: The greatest PSAP-JH was produced by women's tennis and was followed in order by men's soccer, baseball, women's volleyball, women's soccer, and men's tennis; however no differences were statistically significant (p > 0.05). The greatest PSAP-PP was produced by women's tennis and was followed in order by men's soccer, volleyball, baseball, women's soccer, and men's tennis; however, no statistical differences existed (p > 0.05). Statistically significant differences in RS-JH were present between teams (p = 0.031). The greatest RS-JH values were produced by baseball, men's soccer, volleyball and were followed in order by women's tennis and men's tennis and women's soccer. The greatest RS-PP values were produced by men's soccer followed in order by women's tennis, baseball, volleyball, women's soccer, and men's tennis, but no statistical differences existed (p > 0.05). Statistically significant differences in RSImod existed between sport teams (p < 0.001). The RSImod value for men's soccer was statistically greater than the RSImod value of men's tennis (p = 0.007), women's soccer (p < 0.001), and women's tennis (p < 0.001), but not statistically different from baseball or volleyball (p > 0.05). Similarly, the RSImod value of baseball was statistically greater than men's tennis (p = 0.041), women's soccer (p < 0.001), and women's tennis (p < 0.001). Finally, the RSImod of volleyball was statistically greater than women's soccer (p < 0.001) and women's tennis (p < 0.001). Conclusions: According to the PSAP values for both JH and PP, moderate to large effect sizes indicate that women's tennis players may use the SSC the most effectively. However, RS values for JH and PP indicate that men's soccer may use the SSC more effectively than the other teams. Large to very large effect sizes between RSImod values indicate that the men's soccer, baseball, and volleyball teams use the SSC more effectively than the other teams. Practical Application: Although PSAP, RS, and RSImod have been used to assess an athlete's ability to use the SSC, practitioners should be aware that these measures may show vastly different results when comparing individuals and teams. Therefore, it is recommended that practitioners and coaches should consistently use only one of the aforementioned measures when evaluating their players' and team's use of the SSC for the accurate information in regard to changes in ability. Although PSAP, RS, and RSImod are used as measurements of the use of the SSC, practitioners should consider using an alternative method to measure SSC efficiency with regard to tissue mechanics.

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26. Does the Isometric Mid-Thigh Pull Relate to Speed and Change of Direction Performance?

C. Thomas, P. Jones, and P. Comfort

University of Salford

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Purpose: To assess the use of isometric strength testing as a determinant of speed and change of direction performance in collegiate athletes. Methods: Fourteen collegiate athletes (mean ± SD; age = 21 ± 2.4 years; height = 176 ± 9.0 cm; mass = 72.8 ± 9.4 kg) participated in the study. Athletes attended the lab on 2 occasions, at the same time of day. Anthropometric data (height and mass), maximal and explosive strength tests were completed on Day 1, and speed and change of direction (COD) tests completed on Day 2. Maximal and explosive strength was assessed via an isometric mid-thigh pull (IMTP) and counter-movement jumps (CMJ) performed on a FT700 force platform sampling at 600 Hz. IMTP involved 5 seconds trials with peak force (IPF), instantaneous rate of force development (IRFD), impulse at 100 ms (IMTP 100) and 300 ms (IMTP 300) determined. The countermovement jump (CMJ) was performed with hands on hips, with PF (CMJ PF), peak power (CMJ PP), Impulse at 100 (CMJ 100), and 300 ms (CMJ 300) determined. Speed and COD performance was measured using a 20-m sprint (with a 5 m split time) and a 505 test where athletes were instructed to sprint 5 m, turn 180° on their preferred foot, and sprint back 5 m, respectively. For all sprint and COD trials athletes began the test with their front foot 0.5 m behind the start line and time to complete each task was measured using timing cells. For each test athletes completed 3 trials with 2 minutes rest between trials, and 5 minutes rest between IMTP and CMJ tests, and 10 minutes rest between speed and COD tests. Relationships between variables (IMTP, CMJ, and speed and COD) were determined using Pearson's product—moment correlation. Statistical significance was set at p ≤ 0.05. Results: Correlation coefficients between IMTP, CMJ and speed and COD performance are outlined in Table 1. The results suggest that IMTP 300 displayed the strongest relationships with 5- and 20-m sprint performance, whereas CMJ PP displayed the strongest relationship with COD performance. Conclusions: The results demonstrate maximum and explosive force production measures during IMPT could be used as determinants of speed and COD ability in college athletes. However, CMJ PP may be a better marker of COD performance. Impulse at 300 ms during IMTP is recommended as a predictor for sprint performance. Practical Application: Regular performance monitoring requires ease of set up and administration, whilst causing minimal disruption to the training environment. IMTP measures are related to athletic performance (acceleration, speed and COD), and thus are recommended for use in athlete monitoring and assessment, however, dynamic tests (CMJ) may be a better determinant of COD ability.

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27. Short-Term Training Increases Average Power but Not Peak Torque of the Forearm Flexors in Females

D. Traylor,1 T. Housh,2 E. Jesch,1 R. Schmidt,2 J. Cramer,2 G. Johnson,2 H. Bergstrom,3 N. Jenkins,2 K. Cochrane,2 and R. Lewis

1Clemson University; 2University of Nebraska–Lincoln; and 3University of Nebraska

*Award Eligible—Doctoral Student Research Award for an outstanding poster abstract presentation.

Although very short-term resistance training (VST = 3 training sessions) have been shown to increase peak torque (PT) and average power (AP) across a velocity spectrum in the forearm flexors of men (Traylor et al., 2013 and 2014), the minimum number of training sessions needed to increase PT and AP of the forearm flexors of females is unknown (Traylor et al., 2012 and 2014). Purpose: The purpose was to examine the effects of 6 concentric isokinetic training sessions on PT at maximal voluntary isometric contraction (MVIC), 60, 180, and 300°/sec and AP for the forearm flexors at 60, 180, and 300°/sec. Methods: Eleven adult females (mean ± SD; age = 21.5 ± 0.7 years; weight = 64.0 ± 9.2 kg; height = 169.8 ± 6.1 cm) signed an informed consent (visit 1) and completed 2 pretests (visits 2 and 3) and a posttest (visit 10). Testing included maximal, unilateral isometric and concentric isokinetic muscle actions of the non-dominant forearm flexors. During the fourth through ninth visits the subjects performed 5 sets of 10 maximal concentric isokinetic muscle actions of the non-dominant forearm flexors at 60°/sec. A 3 × 4 (time [pretest 1, pretest 2, and posttest] × velocity [MVIC, 60, 180, and 300°/sec]) repeated measures ANOVA was used to analyze PT and a 3 x 3 (time [pretest 1, pretest 2, and posttest] × velocity [60, 180, and 300°/sec]) repeated measures ANOVA was used to analyze AP. An alpha level of p ≤ 0.05 was considered statistically significant for all analyses. Results: For PT, there was no significant time x velocity interaction or main effect for time, but there was a significant main effect for velocity (η2 partial = 0.39). Peak torque decreased with velocity. For AP, however, there was no significant time x velocity interaction, but significant main effect for time (η2 partial = 0.38) and velocity (η2 partial = 0.39). The follow-up t-tests for the marginal means for time (collapsed across velocity) indicated that there was no significant differences in AP between pretest 1 and pretest 2, but the posttest was greater than pretest 1 and pretest 2 at 60, 180, and 300°/sec. Thus, the short-term training resulted in the same pattern of increase in AP for all velocities from pretest 1 and pretest 2 to the posttest. The follow-up t-tests for the marginal means for velocity (collapsed across time) indicated that there were no significant differences in AP between 60 and 300°/sec, but AP was greater at 180°/sec than both 60 and 300°/sec. Conclusions: The present study was the first to show increases (33.5–35.6%) in AP of the forearm flexors across a velocity spectrum after 6 training sessions in females. The training, however, was not sufficient to elicit increases in PT at any velocity (MVIC to 300°/sec). Practical Application: The results of the present study indicated that AP and strength adapt differently in women. These findings provide a rationale for future research in clinical settings designed to define the gender-specific characteristics of upper extremity rehabilitative resistance training programs. Strength and power increases, as a result of short-term training, have implications for patients with limited access to physical and/or occupational therapy due to medical coverage. Furthermore, practice and competition schedules often place time pressures on the rehabilitation and recovery of athletes. Therefore, these findings also have implications for the number of visits that are required for rehabilitation after injury and/or surgery. Future investigations should examine the minimum number of training sessions needed to increase strength of the forearm flexors at various velocities in females.

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28. High-Intensity Interval Training: Effects of Work Interval Duration on Lean Mass and Maximal Cycling Performance

E. Trexler,1 A. Smith-Ryan,1 H. Wingfield,2 M. Melvin,2 and E. Roelofs1

1The University of North Carolina at Chapel Hill; and 2University of North Carolina at Chapel Hill

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Athletes with a need to improve work capacity or body composition often supplement their training with additional cardiovascular exercise. Retention of lean mass and power output may be a concern when incorporating large volumes of cardiovascular exercise, particularly in sports that emphasize strength and anaerobic power. Purpose: To examine the effects of high-intensity interval training with varying work interval durations on body composition, oxygen uptake, and maximal cycling performance. Methods: Fifty-four men (n = 25) and women (n = 29) (Mean ± SD; Age: 36.2 ± 11.7 years, height: 173.5 ± 10.1 cm, weight: 95.9 ± 17.3 kg) with a body mass index ≥25 kg·m2 participated in the current study. Prior to the intervention, body composition was measured using a 4-compartment (4C) model derived from air displacement plethysmography, dual energy X-ray absorptiometry, and bioelectrical impedance spectroscopy. Peak oxygen consumption (

) was determined using a ramp protocol on a cycle ergometer (Corival Lode) increasing 20 watts per minute at a cadence of 60–80 RPMs; respiratory gases were analyzed via indirect calorimetry (True One 2400, Parvo-Medics, Inc., Provo, UT). Peak power output achieved (POW) and time to exhaustion (TTE) during the ramp protocol were also recorded. Participants were randomly assigned to high-intensity short interval (SIT; n = 21), high-intensity long interval (LIT; n = 20), or control (CON; n = 13) groups. SIT and LIT completed 3 high-intensity interval workouts per week for 3 weeks. SIT consisted of 10, 1-minute cycling bouts at 90% of peak power output with 1-minute rest periods. LIT consisted of 5, 2-minutes bouts with 1-minute rest periods, with undulating intensities ranging from 80-100% of peak power. Cumulative work durations for LIT and SIT each totaled 10 minutes per session. Pre- and post-test measurements of body composition, oxygen uptake, and cycling performance were compared using a series of paired samples t-tests. Results: LIT and SIT both increased

significantly (2.65 ± 0.79 to 2.84 ± 0.73 L/min, p = 0.002; 2.62 ± 0.68 to 2.88 ± 0.77 L/min, p < 0.001, respectively), but CON did not (2.54 ± 0.93 to 2.61 ± 0.97 L/min, p = 0.44). Lean mass increased significantly in the LIT group (60.9 ± 12.5 to 62.5 ± 11.6 kg; p = 0.004), but not in SIT (65.7 ± 12.8 to 66.5 ± 11.6 kg, p = 0.079) or CON (66.6 ± 15.8 to 67.8 ± 16.3 kg, p = 0.217). LIT and SIT improved POW (210.8 ± 52.7 to 226.1 ± 48.0 W, p = 0.004; 210.7 ± 49.5 to 232.3 ± 51.2 W, p < 0.001) but CON did not (191.5 ± 62.5 to 191.3 ± 69.6 W, p = 0.97). LIT and SIT also increased TTE (875.0 ± 153.1 to 933.5 ± 145.3 seconds, p < 0.001; 872.8 ± 146.5 to 934.1 ± 154.8 seconds, p < 0.001), whereas CON did not (819.4 ± 187.6 to 818.4 ± 210.7 seconds, p = 0.935). Conclusions: In overweight and obese individuals, 3 weeks of SIT and LIT both improved

, POW, and TTE in maximal cycling. Only LIT increased lean mass to a significant degree, but the SIT group trended toward significance (p = 0.079). Practical Application: LIT and SIT are both suitable strategies for conditioning, particularly when power and lean mass retention are of high priority. The increased work duration of LIT may impart a greater anabolic stimulus than that of SIT, potentially indicating a more favorable effect on retention of lean mass. Acknowledgments: Supported by the Nutrition Obesity Research Center (P30DK056350).

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29. Trunk Muscle Endurance Times in Weight Training Females

W. Hanney,1 M. Kolber,2 P. Pabian,1 P. Salamh,3 C. Rothschild,1 M. Hinton,1 and R. Rivers1

1University of Central FL; 2Nova Southeastern University; and 3SEO Physical Therapy

Purpose: To date, trunk endurance times have been reported in the literature for the purpose of evaluating normative hold times as well as endurance ratios. These values have been reported among healthy females but has not been investigated in the female weight training population. Therefore, the purpose of this study was to establish isometric endurance times of trunk muscles and their ratios among a group of weight training females to use as a reference for both performance and risk assessment. Methods: Participants were females (mean 27.61 years ± 9.98) that participated in regular weight training at least 3 times per week. Primary assessments included endurance times of the trunk flexors, trunk extensors, as well as the left and right lateral trunk muscles measured in seconds. Ratios of each endurance time were calculated relative to the extensor muscle endurance time. Means ± standard deviations (SD) were calculated for each of the test positions. Additionally, ratios of each mean endurance time was normalized to the mean extensor endurance time to allow for comparison across studies. Finally, t tests were performed to assess differences of the timed scores between the trunk flexor and trunk extensor tests as well as between the left and right side bridge tests. Results: Sixty-one women were recruited to participate in this study. The mean flexor endurance time was 162.7 s ± 105.9 while the mean extensor endurance time was 104.6 s ± 56.6. Side-bridge left demonstrated mean values of 66.1 s ± 38.1, while the right side bridge mean values were 61.1 s ± 33.2. There was a significant difference between the trunk flexor and extensor tests (p = 0.00), but not between left and right side bridge tests (p = 0.06). Ratios normalized to the extensor test were 1.56 for flexor, 0.63 for left side bridge and 0.58 for right side bridge. Conclusions: Female recreational weight training participants were found to have significantly greater trunk flexor endurance compared to trunk extensor endurance, with no significant difference between left and right lateral trunk flexor endurance. The mean flexor endurance time was the highest of all mean endurance times however also demonstrated the largest variance. The flexor ratios found in this study are in contrast to previous endurance ratio data. Practical Application: Differences should be taken into consideration when evaluating the trunk endurance times of weight training females for training and rehabilitation purposes as endurance weakness of the extensors compared to flexor muscle groups has been implicated as a risk factor for developing low back pain.

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30. Relationship Between PEAK and Average Power of the Drive-Block in Football Offensive Line Play With Strength and Power Measures

B. Jacobson, E. Conchola, and D. Smith

Oklahoma State University.

Strength and power are vital components of American football and training of these variables is a year-round requirement conducted in sophisticated facilities and supervised by strength and conditioning professionals. For offensive linemen the drive-block is a principal technique in the running game and is designed to move the opponent in a particular direction. Maximizing strength and power to augment the effectiveness of blocking is year-long endeavor in American football. However, little can be found to verify that the typical exercises actually correlate with on-the-field play. Two of the common strength exercises for football are the squat and power clean which are routinely assessed along with the vertical jump. Purpose: The purpose of this study was to investigate the relationship of peak power (PP) and average power (AP) of the drive-block to 1-RM squat, 1-RM power clean, body mass (BM), and percent fat (%). Methods: Following IRB approval, PP and AP were assessed using a Tendo Power and Speed Analyzer as the linemen exploded into a blocking dummy from a 3 point stance. 1-RM assessments for the squat and power clean (PC) were recorded along with vertical jump (VJ) distance, body weight and percent fat. These data were correlated with PP and AP of the drive-block. Results: Means for each variable were: BM 136.29 + 8.19 kg, squat 457.69 + 81.81 kg, power clean 280.77 + 35.17 kg, and body fat 24.44 + 6.12%. Pearson Product correlations yielded significant (p ≤ 0.05) relationships between both PP and AP of the drive block and the 1-RM squat and PC. A significant relationship was also found between AP and VJ. Practical Application: These data help serve to verify the usefulness of the squat and PC in an offensive line training protocol.

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31. Effects of an Ultra-Endurance Event on Energy Balance, Body Composition and Training Adaptations: A Case Study

A. Jagim,1 K. Levers,2 E. Galvan,2 D. Joubert,2 M. Greenwood,2 C. Rasmussen,2 and R. Kreider2

1Gannon University; and 2Texas A&M University

Introduction: Ultra-endurance events are becoming increasingly popular. Typically, these events are defined as endurance competitions lasting longer than 6 hours or 100 miles in duration. However, several competitions consist of consecutive days or weeks at these distances and therefore it is unknown how the body will respond to the demands placed upon it in these conditions. By better understanding the physiological demands of an event of this nature, athletes can better prepare themselves through proper training and nutritional practices. Purpose: The purpose of this case study was to observe the effects of a self-supported ultra-endurance mountain cycling event on energy balance, body composition, lower and upper body strength, anaerobic capacity, aerobic capacity and markers of clinical health. Methods: A trained endurance cyclist participated in this case study by competing in the self-supported ultra-endurance event known as the Tour Divide mountain bike race in the spring of 2013. The subject cycled approximately 8,835 total kilometers in 44 days south-to-north and north-to-south over the U.S. and Canadian Continental Divide interspersed with climbs totaling nearly 121,920 meters on the race route. Body composition, physical performance, and markers of clinical health were collected pre-race and up to 3-week post-race. Results: Average total energy intake increased by 1,541 kcals during the race compared to pre-race food consumption. We observed an increase in carbohydrate (113%) and fat (12.85%) intake with a marked decrease in protein consumption (−28%). The participant lost a total of 8.4 kg over the course of the 44-d trek and remained 11.0 kg below pre-race weight 3-weeks post-race. The participant lost fat (−7.2 kg) and fat-free mass (−1.9 kg) over race period, resulting in a 6.4% decrease in body fat. Upon completion of the race, the participant experienced a decrease in absolute Peak

, mean power, and peak power measured by a Wingate Anaerobic Capacity Test 96-hours post-race that remained depressed 3-weeks post-race. Additionally, upper and lower body muscular strength endurance performance decreased 96-hours post-race (−50/−57% and −67%, respectively). Parameters of liver function, AST and ALT, were elevated immediately post-race (92% and 95%, respectively) and remained 46 and 58% above normative values 96-hours post-race. Creatine kinase concentration also significantly increased (210%) immediately following the race and remained elevated 24 (30%), 48 (46%) and 72-hours (20%) post-race. Conclusions: We conclude that completing a 44-d extreme ultra-endurance mountain biking race results in a significant decrease in fat and fat free mass. Additionally, prolonged ultra-endurance performance facilitates decreases in aerobic capacity, anaerobic power, muscular strength endurance as well as increases in markers of muscle damage. Practical Application: Based on the results of the study, it is recommended that anyone competing in an ultra-endurance event significantly increase their energy intake with an emphasis on protein in order to off-set the high energy expenditures common to races of this nature and limit its catabolic effects. Acknowledgments: This study was supported by a grant from the Sydney & J.L. Huffines Institute for Sports Medicine and Human Performance.

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32. Effect of Concurrent Sprint Interval and Resistance Training on Measures of Strength, Power, and Aerobic Performance

R. Laird,1 S. Kennedy,2 D. Elmer,3 L. Salom,2 K. Lee,2 and M. Barberio4

1McDaniel College; 2Auburn University; 3Berry College; and 4George WA University School of Medicine and Health Sciences

Purpose: The purpose of this investigation was to determine the effect of sprint interval (SIT) and resistance training performed concurrently on measures of strength, power, and

compared to resistance training alone in recreationally active females. Methods: 28 healthy females (20.3 ± 1.7 years, 35.4 ± 4.0 ml·kg−1·min−1

, 113 ± 17 lbs. 1 repetition max (1 RM) back squat) were asked to complete a 12 weeks training program. Pre and post testing consisted of 1 RM back squat, maximal isometric squat, rate of force development (RFD), anaerobic power evaluation, lactate threshold (LT), and

. Following initial testing, participants were paired according to 1RM back squat and

values and randomly assigned to 1 of 2 groups: concurrent training (CT) that completed both resistance and SIT protocols, and resistance training (RT) which only completed the resistance training protocol. Training was completed 3 days per week and lasted for 12 total weeks. Resistance training was completed before noon with each participant trained at the same time each day. Separated by at least 4 hours, CT participants returned and completed SIT. Results: 1 RM squat and maximal isometric force values were significantly elevated following training in both RT and CT (both p < 0.01). RFD was not significantly altered in either group. Wingate testing revealed significant increases to peak and mean anaerobic power values in both ST (p ≤ 0.05) and CT (p < 0.01) with no statistical difference between group response differences.

also increased as a result of resistance and concurrent training (p < 0.01). Predicted zero incline velocity resulting in

(Vmax) values were significantly elevated in both groups (p < 0.01) although concurrent training resulted in a significantly greater adaptive response (p < 0.01). LT also increased significantly in both groups following training (p < 0.01). Conclusions: These data indicate that resistance training in isolation and sprint interval based concurrent training result in identical improvements to measures of strength, power, and

with no indication of adaptive interference. Only Vmax adaptations supported the hypothesis of synergistic enhancement. These findings may be the result of commonalities between the adaptive responses to sprint interval and resistance training. Practical Application: The results of this study suggest that it is possible to complete SIT and resistance training concurrently without adaptive interference. Coaches designing programs for athletes where improvements in strength, power, and endurance are prerequisites for performance enhancement should evaluate how SIT or other high intensity interval training might supplement programs already in place. Acknowledgments: This research was funded by Auburn University No Conflicts.

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33. The Relationship Between the Functional Movement Screen and Dynamic Stability as Measured by the Star Excursion Balance Test in Team Sport Athletes

R. Lockie,1 S. Callaghan,2 C. Jordan,3 T. Luczo,4 and A. Schultz1

1University of Newcastle/Exercise and Sport Science; 2Edith Cowan University; 3University of Newcastle; and 4California State University of Monterey Bay

The Functional Movement Screen (FMS: deep squat; hurdle step [HS]; in-line lunge [ILL]; shoulder mobility; active straight-leg raise; trunk stability push-up [TSPU]; rotary stability), is used to detect movement deficiencies, although research has suggested the FMS may not detect limitations that could affect athletic performance (e.g., multidirectional sprinting). Dynamic stability, which is a component of speed, could be indicated by certain FMS actions which feature unilateral support. The Star Excursion Balance Test (SEBT) is used to assess dynamic stability, through functional reaching in 8 directions (Figure 1). No research has analyzed the relationship between the FMS and SEBT. Purpose: To ascertain whether athletes who display superior dynamic stability also perform better in the FMS; to determine relationships between the SEBT and FMS. Methods: Forty-one team sport athletes (32 male, 9 female) were assessed in the FMS in 1 session, and the SEBT in another. Subjects were ranked according to the total reach score (sum of all excursions) when both the left and right leg were used for SEBT stance, and split into high-, intermediate, and low-performing groups (n = 13 for each group). To ensure the groups had different dynamic stability capabilities for the 2 dichotomization methods, subjects ranked 14 and 28 were removed. Between-group differences in the FMS and SEBT were calculated via a one-way analysis of variance with Bonferroni post hoc adjustment (p ≤ 0.05). Data was pooled (n = 41) for a correlation analysis (p ≤ 0.05) between the FMS and SEBT. Results: There were few significant between-group FMS differences, even though the high-performing groups were clearly superior in dynamic stability when each leg was used for SEBT stance. The high-performing group was better in the HS and ILL when compared to the intermediate group for the right leg stance SEBT (p = 0.017–0.026); no between-group differences in the FMS were established for the left leg stance SEBT. The HS, ILL, and TSPU correlated with anterior and lateral plane excursions (r = 0.315–0.476). There were no relationships between the FMS and excursions stated to be the most challenging (posteromedial, medial, anteromedial). Conclusions: The ILL and HS provided a limited indication of dynamic stability, as better-performing athletes scored higher, and the screens related to certain excursions. However, no other screens differentiated subjects of different dynamic stability levels, and any significant correlations between the FMS and SEBT were moderate (r < 0.05). The posteromedial, medial, and anteromedial excursions had no relationship to the FMS. The FMS has limited function for identifying movement limitations that could affect dynamic stability. Practical Application: The FMS may not provide an indication of an athlete's dynamic stability. However, strength coaches could use the SEBT to delineate between athletes of different dynamic stability capabilities, and to monitor changes to performance.

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34. The Influence of Instrument Assisted Spinal Mobilization Applied During Mechanical Spinal Distraction on Asymptomatic Subjects

C. Proulx,1 J. Gallo,2 and J. Murphy3

1New York Chiropractic College; 2Salem State University; and 3Charleston Southern University

Introduction: The majority of adults will experience a debilitating bout of low back pain at some point. In the athletic population, low back pain accounts for a significant amount of time lost in competition as well as training. In addition, in the absence of pain, low back injury and fatigue continues to reduce performance locally in the lower extremities. The use of mechanical spinal distraction has been used to decrease motor neuron excitability and thereby decreasing muscle activity and performance of the paraspinals and extremities distal to the point of application. High velocity mobilization and manipulation procedures combined with spinal distraction have been implicated as a potential approach to treating spinal conditions and facilitating recovery and enhancement to motor control. Purpose: As an initial investigation, the intent is to determine the local muscle activity responses to a controlled instrument mobilization technique to the lumbar spine while under mechanical spinal distraction. Methods: The study was a single trial within subject design. The study took place in the clinical laboratory at a University. Subjects (n = 9) were men and women healthy volunteers from the student population at the University. All subjects were screened for contraindications as well as previous history of recent low back pain or injury, less than 1 year as well as any contraindications to the treatment. Subjects were secured to a low coefficient lumbar spinal distraction system in the prone position. All subjects received the same progression to reach a total of 18.18 kg of final distraction force. At maximal intensity, subjects will be held in spinal distraction for 1 minute, prior to mobilization. Mobilization was applied at the L3 transverse process with the intent of producing a rotation moment, opposite the side of electromyography application. Main outcome measures included surface electromyography of the right lumbar paraspinals and middle trapezius collected in standing (for comparison), lying prone on distraction table prior to distraction force application and after 1 minute reaching maximal distraction force of 18.18 kg, during mobilization application, immediately following mobilization and 1 minute after mobilization. Repeated measures analysis was used to determine effect, if any, of controlled instrument assisted mobilization of the lumbar spine during spinal distraction. Results: There was no significant difference in muscle activity of the erector spinae when lying prone with no distraction force, during at maximal distraction force, immediately after mobilization or 1 minute after mobilization, in any comparison (p > 0.05). Standing and during mobilization resulted in significantly higher muscle activity (p < 0.0.5). There was no significant difference in muscle activity in any situation of the middle trapezius (p > 0.05). No adverse events were reported. Conclusion and Practical Application: In normal subjects, the addition of mobilization during mechanical spinal distraction did not create adverse responses to what might be considered a potential treatment in the spinal patient. Independently, these techniques have shown to have clinical value, however there has been little information on combining these techniques to determine the added benefit. If spinal distraction is successful in reducing motor neuron excitability and hence muscle activity that may be resistant to mobilization, this effect may prove to be advantageous. The combined technique may allow clinicians to utilize lower forces when applying mobilization and manipulation techniques, decrease the potential of adverse reactions, create enhanced recovery approaches from intense training, as well as potentially increasing specificity of treatment. Further clinical studies are needed to determine if this approach is a viable method of improving outcomes or enhancing recovery.

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35. The Effects of Practical Vascular Blood Flow Restriction Training on Maximal Muscular Strength

B. Campbell,1 J. O'Halloran,2 N. Martinez,3 N. Theilen,2 J. Wilson,4 and M. Kilpatrick2

1University of South Florida/Exercise and Performance Nutrition Laboratory; 2University of South Florida/Exercise and Performance Nutrition Laboratory; 3University of South Florida; and 4University of Tampa Human Performance Lab

Practical blood flow restriction training is a new training technique that has the potential to increase muscular hypertrophy and muscular strength while allowing practitioners to train with lighter loads (20–30% of 1-RM). Through the use of elastic knee wraps, the limbs can be restricted using a perceived pressure scale. The comparison of practical blood flow resistance training with traditional, non-blood flow restricted resistance training and its effects on muscular strength has not been investigated. Purpose: The purpose of this study was to compare the effects of practical vascular blood flow restriction training (BFR) to traditional resistance training during a 4-week period in trained, college-age males. Methods: Twenty-one resistance-trained males participated in a 4-week training program and were randomly assigned to 1 of 2 groups: Practical BFR training (BFR; n = 10) and Resistance training (RT; n = 11). The primary difference between the groups was the BFR group performed approximately 62% of all sets blood flow restricted at 20–30% of 1-RM while the RT group performed all sets at an intensity of >70% 1-RM in a traditional manner (non-blood flow restricted). Perceived pressure for blood flow restriction in the BFR group for the arms and legs was 7 out of 10. Workouts for both groups were similar and consisted of whole body routines ∼3 d/wk. A 2 × 2 repeated measures ANOVA was used to assess group, time, and group by time interactions. Statistical significance was set to p ≤ 0.05. Results: There was a no difference in total lifting volume between the 2 groups. There was a main effect for time for bench press 1RM (p = 0.001) and Leg Press 1RM (p < 0.001). Specifically, BFR improved from 220.5 ± 65.1 to 235.0 ± 50.6 pounds and from 822 ± 135.9 to 952.5 ± 168.9 pounds in the bench press and leg press, respectively. The RT improved from 245.9 ± 60.9 to 257.7 ± 53.5 pounds and from 780.5 ± 192.4 to 957.3 ± 213.4 pounds in the bench press and leg press, respectively. No interaction effects were observed for bench press 1RM (p = 0.708) or leg press 1RM (p = 0.134). Conclusions: Four-weeks of practical blood flow restriction training is as effective for inducing maximal bench press and leg press strength as compared to traditional resistance training, despite training at low percentages of subjects 1-RMs. Practical Application: Our results suggest that coaches and athletes can improve strength with BFR to a similar extent to high intensity training. This could have implications for injured or overreached athletes who cannot handle heavier training loads. Acknowledgments: This investigation was supported by Dymatize Nutrition Sport Performance Institute.

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36. Comparison of 1 Repetition Maximum Barbell and Dumbbell Bench Press

B. Church,1 W. Jackson,2 L. Bryant,1 M. Jones,1 T. Adams,1 and J. Stillwell1

1Arkansas State University; and 2East Arkansas Community College

Purpose: The purpose of this investigation was to determine the relationship between 1-repetition maximum barbell bench press (BBP) and 1-repetitionmaximum dumbbell bench press (DBP) in college-aged males. Methods: Fifty-six college-aged males (mean ± SD; age = 18 ± 2.2 years; height = 177.4 ± 9.2 cm; weight = 82.4 ± 14.0 kg) volunteered to participate in this investigation. Participants' 1-RM in the BBP and DBP was measured on days separated by a minimum of 48 hours. The order was divided so that half performed the BBP first. A standardized warm-up was used for both exercises. The DBP 1-RM was reported as the sum of the weight of the 2 dumbbells. Statistical analysis included means and standard deviations, Pearson correlation coefficient, simple regression analysis, and one-way ANOVA. Statistical significance was set at p ≤ 0.05. Results: Results revealed that participants performed significantly better in the BBP than the DBP (p ≤ 0.05). Means and standard deviations were as follows: BBP (M = 189.1 lbs, SD = 44.2), and DBP (M = 235.4 lbs, SD = 57.9). A Pearson correlation was performed which revealed a correlation coefficient of r = 0.92 (p ≤ 0.05). Further analysis produced the following simple regression equation: DBP = 0.698(BBP) + 24.8. Conclusions: These results revealed a clear difference in average values for BBP and DBP 1-RM, presumably due to the fact that the arms work independently when using dumbbells. Although DBP strength was less, a high correlation coefficient indicates the predictive potential between the 2 variables. Practical Application: The practitioner may use this information to help understand the relationship between strength in the BBP and DBP. The simple regression equation may be used to estimate DBP from BBP or vice versa. This may potentially reduce the amount of time required to establish a 1-RM. In addition, it may be advantageous to use the prediction to reduce the effort required and the potential injuries that may occur with heavy loads. Acknowledgments: This investigation received no funding.

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37. Short-Term Changes in Isometric Bench Press Strength Among Trained and Untrained Young Adults

S. Dorgo,1 R. Reed-Jones,2 P. Ambati,1 and N. Murray1

1University of Texas at El Paso; and 2University of Prince Edward Island

Despite the known principle of training-testing specificity, previous research showed that dynamic movement based resistance training may have carry-over effects to isometric (static) strength testing. However, the exact carry over effects between trained and untrained subjects training at different intensities has been unclear. Purpose: To compare the short-term isometric bench press strength changes between young adults with and without bench press specific resistance training experience. Methods: Thirty-nine untrained adults (mean ± SD age: 23.5 ± 3.9; BMI: 25.4 ± 5.2) with no current engagement in regular resistance training and no training experience with the bench press exercise were assigned to one of the following groups using blocked randomization: (a) training with overload intensities (OR); (b) training with minimal intensities (MR); and (c) control subjects with no training. An additional 14 trained adults (mean ± SD age: 23.3 ± 3.9; BMI: 25.0 ± 3.4) formed the trained (TR) intervention group. Subjects' strength was assessed by an isometric bench press test with relevant force plate data collected, and by the 1RM bench press test. Following pre-testing, subjects completed 6 weeks of resistance training, with 2 sessions weekly, each comprised of 3 sets of 10 repetitions. The TR and OR groups used 75% of their latest measured 1RM, while the MR group used a weightless 5 ft. PVC pipe. Subjects in the control group were asked to refrain from any resistance training. Isometric strength and 1RM follow-up tests were administered every 2 weeks. Data were analyzed using a general linear mixed model and alpha level was set at p ≤ 0.05. Results: There were no initial strength differences between the untrained groups (OR, MR, and Control) for the isometric bench press test (p > 0.58). TR group was significantly stronger than any of the untrained groups (p < 0.0006) at pre-test and remained significantly stronger through all follow-up tests (p < 0.009), despite a 5.3% actual decrease in isometric bench press strength (p = 0.038) from pre-test to post-test. Similarly, the MR and Control groups showed a decrease in isometric strength from pre-to post-test (−4.3% and −0.3%, respectively), although both were statistically non-significant (p > 0.71). On the contrary, a significant (p = 0.0427) isometric strength increase was observed in the OR group (8.4% improvement). A significant group-by-time interaction (p = 0.0462) was observed among the 4 groups, confirming a different isometric strength change pattern across the groups. At the same time, pre-to post-test 1RM bench press strength increased significantly in the TR, OR, and MR groups (p < 0.0001), but remained unchanged (p = 0.123) in the Control group. Conclusions: While training with minimum resistance training intensities was sufficient to elicit 1RM bench press strength improvements in the MR group, these changes had no carry-over effect to isometric bench press strength. The same phenomenon was observed in the trained group, which despite improving the 1RM strength actually decreased in the isometric strength performance. A carry-over effect was observed only among those untrained subjects who trained at overload intensities. Practical Application: Strength improvements are most likely to be observed if similar movements and muscle contraction patterns are used both during training and testing. Dynamic strength training likely carries over to static strength improvement only in untrained subjects.

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38. Accuracy of the NFL-225 Test to Estimate 1RM Bench Press in African-American College Football Players

M. Heinecke1 and D. Mayhew2

1Winston–Salem State University; and 2Truman State University

The NFL-225 test has received considerable attention as a technique for predicting one-repetition maximum (1RM) bench press in college football players. Most of the prediction equations have been produced using mixed racial samples of players. A previous study suggested that a race variable improved prediction accuracy of NFL-225 equations. However, the investigators did not actually utilize a race coefficient in their regression equation to estimate 1RM from NFL-225 repetitions, and thus this assumption has never been adequately tested. Purpose: The aim of this study was to determine the accuracy of NFL-225 prediction equations for estimating 1RM bench press in African-American college football players. Methods: Sixty-six African-American football players from an NCAA Division II school were assessed prior to off-season training for 1RM bench press and repetitions completed with 102.3 kg (225 lbs). Test sessions typically occurred within 1 week of each other. Repetition groups were established as Gr 1 (1–10 reps), Gr 2 (11–20 reps), and Gr 3 (>20 reps). Actual 1RM bench press was compared to predicted bench press values produced from 9 NFL-225 prediction equations from the literature. Results: Intraclass correlation coefficients (ICC) for all prediction equations were greater than 0.964. Four of the prediction equations produced 1RM estimates that were not significantly different from actual 1RM, although the equations underestimated by 1.3–2.5 kg (CV = 5%). There was no significant difference among the 3 repetition groups for the difference between predicted and actual 1RM for any of the 9 equations. The best equation produced 74% of the players with predicted 1RM values within 5% of actual 1RM and 92% within 10% difference. The larger differences between predicted and actual 1RM were produced by those with greater actual 1RM values and who did more NFL-225 repetitions. Conclusions: Several NFL-25 prediction equations in the literature are acceptable for predicting 1RM bench press in African-American college football players. These are the same equations that have shown acceptable validity in mixed racial samples in other studies. Unfortunately, the study that suggested a race variable improved prediction accuracy did not provide an acceptable equation with a race factor to determine how much it reduced the prediction error when estimating 1RM bench press from NFL-225 repetitions. Practical Application: Strength and conditioning specialists can be confident that several currently available NFL-225 prediction equations provide acceptable estimates of 1RM bench press in the majority of African-American players.

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39. Acute Effects of an Elastic Resistance Drill on Baseball Catching Throw-Downs

A. Fry,1 L. Frickey,1 M. Lane,1 M. Andre,2 A. Joice,1 and M. Reddy1

1University of Kansas; and 2University of Wisconsin–LaCrosse

A critical component of success for a baseball catcher is the ability to rapidly throw-down to second base to catch a stealing base runner. Anecdotal evidence suggests throw-down performance may be improved by training the motion while working against elastic resistance. Purpose: To determine the acute effects of practicing the baseball catching throw-down motion while working against elastic resistance. Methods: Trained and experienced baseball catchers participated in this study (n = 8; X ± SD; age = 22.0 ± 5.6 years, height = 1.80 ± 0.05 m, BW = 84.3 ± 9.3 kg, catching experience = 5.5 ± 1.1 years). Before (pre) and after (post) each of 2 testing sessions, subjects were filmed while performing 5 repetitions of the throw-down motion using high speed videography (240 Hz, 4.2 ms resolution). A pitching machine simulating 70-75 mph fast balls provided consistent pitches. Video was analyzed for time elements using Kinovea v0.8.15. Variables included ball transfer time (ball in mitt to hand on ball), throwing motion time (removal of ball from mitt to release of ball), and total ball handling time (transfer time + throwing motion time). A radar gun recorded the resulting throwing velocity. Transfer time, throwing time, and ball velocity were used to derive catcher pop times (total time from ball in mitt to arrival at second base). During 1 test session (Resistance), subjects performed 3 x 5 repetitions of a catcher throw-down drill while attached to a Vertimax training device. Elastic bands were attached to the rear ankle and the wrist of the mitt hand. Resistance varied from 50 to100 N through the ranges of motion used. During the Control testing session, the throw-down drill was performed without the Vertimax. Data were analyzed with 2 x 2 RMANOVAs and dependent t-tests (p ≤ 0.05). Results: No significant differences were found for any variable in the following table, or for any change score (p > 0.05). See table. Discussion: It was anticipated that ball transfer would be improved immediately after performing training with resistance. This could be due to enhanced gross movement patterns immediately following the resistance work, or possibly to a post-activation potentiation effect. This lack of an acute training response could be due to the moderate training status and experience of the subjects, a relative unfamiliarity with the training device, or the modest resistances used for this study. It is also possible that prior technique training for the throw-down motion is required to permit the training modality to be used effectively. Practical Application: It is possible that the catcher throw-down training against resistance such as used in the present study is an advanced exercise requiring considerable familiarization and long-term practice. The present data indicate there is not an acute benefit from this exercise. Future study is needed to determine if this exercise is effective with other levels of catchers and with consistent long-term training.

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40. Binge Drinking Following Heavy Eccentric Resistance Exercise: Effect on Muscle Power Recovery in Women

T. Layman, A. Duplanty, R. Budnar, H. Luk, C. Cregar, N. Idemudia, A. Fernandez, D. Levitt, D. Hill, and J. Vingren

University of North TX

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Purpose: To investigate the effect of alcohol on explosive performance measures during recovery from heavy eccentric resistance exercise. Methods: Ten healthy women (Mean ± SD: 22.2 ± 1.2 years, 164.9 ± 4.4 cm, 62.2 ± 6.2 kg, 25.6 ± 5.3 body fat %) completed 2 identical acute heavy resistance exercise tests (AHRET) separated by 1 week. The AHRET consisted of 4 sets of 10 repetitions of eccentric smith machine squats at 110% of 1-repetition maximum (1-RM) with 4 minutes of rest between sets. The first AHRET session was used as preconditioning and no performance measures were obtained. The second and third AHRET sessions were used for the experimental protocol. On these 2 visits participants consumed a drink containing either alcohol (EtOH; 1.086 g of alcohol per kg lean mass; 82–122 ml total) or Placebo (no alcohol) from 10-30 minutes post-AHRET. The participants were blinded to conditions and the order of conditions was counter-balanced. Blood alcohol concentration (BAC) was measured using a breathalyzer. Before the AHRET (PRE), and 24 and 48 hours post AHRET, participants performed 3 consecutive vertical jumps on a force plate, 20 yard shuttle runs, and 20 yard sprints, all at maximal effort. Muscle soreness was measured using analog scales at PRE and 24 and 48 hours. Results: BAC peaked 60–80 minutes post-exercise in all participants (0.10 g·dl−1 ± 0.01) on alcohol ingestion days. No effect (p > 0.05) of alcohol was found for vertical jump peak power (EtOH, PRE: 37.6 ± 3.3 W·kg−1, 24 hours: 34.2 ± 5.6 W·kg−1, 48 hours: 37.5 ± 6.8 W·kg−1; Placebo, PRE: 36.4 ± 5.0 W·kg−1, 24 hours: 37.0 ± 5.0 W·kg−1, 48 hours: 37.2 ± 3.6 W·kg−1), vertical jump height, shuttle run time or 20 yard sprint time. Leg soreness increased moderately from PRE (EtOH: 1.2 ± 1.1; Placebo: 0.7 ± 0.7) to 24 hours (EtOH: 2.7 ± 1.4; Placebo: 1.9 ± 1.2) with no difference between conditions. Conclusions: A moderate-high BAC does not appear to affect explosive lower body power capability 24 and 48 hours following a heavy eccentric squat session that induces moderate muscle damage. Practical Application: Moderate alcohol consumption post exercise may not influence lower body soreness or power performance in the short term recovery period.

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41. Effects of Different Types of Strength Training on Bone Mineral Density and Muscle Mass in Middle-Aged and Elderly Adults

L. Lin,1 M. Lo,2 M. Chen,1 H. Chow,1 T. Lin,1 and Y. Tsai1

1National Cheng Kung University; and 2Kun Shan University

Purpose: To examine the effects in bone mineral density and lean muscle mass after 24 weeks of exercise intervention with 3 different exercise intensities and mode of exercises in middle-aged and elder adults. Methods: 53 healthy volunteers aged 51–70 randomly assigned to 4 groups after a pre-maximum strength test (control group, n = 13; moderate-load resistance group, n = 14; high-load resistance group, n = 13; multi-component exercise group, n = 13). There were 75 minutes progressive training program for exercise groups for 2 days per week following 24 weeks. Exercises include of total body workout using 9 different resistance training machines, 2 sets of 50%of 1RM (13–15 reps) for moderate-load resistance group and 2 sets of 80% of 1 RM (8–10 reps) for high-load resistance group. Multi-component exercise group performed 1 set of 50% of 1 RM (13–15 reps) of resistance training and 30 minutes of aerobic exercise. Control group was asked to maintain life style as usual without additional exercise. The bone mineral density and body conposition of upper and lower limbs were measured by dual-energy X-ray absorptiometry before and after training (0/25 weeks). Results: After 24 weeks, the bone mineral density of lumbar spine had decreased 1.7% in control group. The exercise groups had also shown dissimilar adaptation according to different part of body compared to different groups. The bone mineral density of high-load resistance group had increased +0.8% after training and showed significantly higher (+1.5%) than control and multi-component group in legs (p ≤ 0.05). Muscle mass in exercise group (+1.7–2.8%) improved arm lean mass more than control group (−0.7–1.3%) (p ≤ 0.05). Conclusions: The high-load resistance training program has beneficial effects on bone mineral density in middle-aged and elder adults and moderate-load resistance group and multi-component group only delay the onset of aging. However, similar responded and effect of lean muscle mass were shown between exercise groups. Acknowledgments: We would also like to thank the National Science Council of Taiwan for financially supporting the work under contract no. NSC101-2410-H-006-121.

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42. Lifting Performance and Indices of Recovery 24 Hours after Exhaustive Resistance Training Bouts in Adolescent Males

J. Mitchell,1 R. Herron,2 S. Carter,2 A. Collins,2 A. Martinez,1 S. Baggett,1 and P. Bishop2

1University of Alabama; and 2The University of Alabama

Purpose: Resistance training is a major component used by athletes to achieve peak performance. While training frequency guidelines recommend 2–3 nonconsecutive days per week, many adolescents train on consecutive days. We examined the relationship of lifting performance and self-reported indices of recovery in adolescent athletes. Methods: Eighteen trained male (mean ± SD; age = 16.0 ± 2.0 years) high school athletes performed 3 sets to failure in bench press and back squat exercises. Measures were taken at baseline and following a 24 hours recovery period. Participants provided information on hours of sleep, time of last meal, and feelings of hunger, tiredness, and recovery 24 hours after baseline. The level of recovery was evaluated from the number of repetitions performed during the athletes first set of each exercise in comparison with baseline measures. Full recovery was defined as meeting or exceeding the number of repetitions completed during baseline. Performance differences between baseline and the 24 hours assessment in bench press and back squat were compared to hours of sleep and time of last meal, in conjunction with subjective feelings of recovery, tiredness, and hunger to determine relationship significance. Pearson r correlation revealed a significant negative correlation between bench press performance difference and amount of sleep (r = −0.64, p = 0.004). Significant negative correlations were found between back squat performance differences and participants' feelings of tiredness (r = −0.54, p = 0.02), hunger (r = −0.62, p = 0.01), and time of last meal (r = −0.47, p ≤ 0.05). Significant correlations were not found between bench press and feelings of tiredness (r = −0.31, p = 0.22), recovery (r = 0.02, p = 0.93), hunger (r = −0.17, p = 0.50), and time of last meal (r = 0.03, p = 0.91). Additionally, a correlation was not found between the amount of sleep (r = 0.46, p = 0.05) and performance difference in back squat; however, this relationship warrants further investigation. Conclusions: Results suggest monitoring sleep status and subjective feelings of recovery and hunger in adolescent athletes could improve resistance training program design to elicit more favorable results.

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43. The Acute Effect of Pilates Exercise on Lower Extremity Maximal Strength

H. Monger and B. Harrison

Longwood University

Purpose: The term “core function” can be described as the ability of the anatomic core to accelerate, decelerate, or stabilize the Lumbo-Pelvic-Hip complex in all 3 planes of motion successfully according to the demands being placed on the body. Due to the widespread acknowledgment of the importance of appropriate core function in maximizing human performance, exercises designed to improve core function are common components of strength and conditioning programs across sports and recreation. Currently, there is a lack of sufficient data to allow strength and conditioning professionals to create evidence-based core function training programs despite their popularity. Pilates is an exercise modality commonly associated with an emphasis on improving core function. Pilates training has been shown to improve control over anatomic core muscles in asymptomatic, healthy adults. While the chronic effects of core training programs, including Pilates programs, on athletic performance have been examined, the acute effects of core training on athletic performance variables have yet to be determined. Incorporating core training into a movement preparation or warm-up protocol may elicit greater positive responses than a general, low-intensity, aerobic warm-up in the context of a training session involving maximal or near-maximal strength efforts. Therefore, the purpose of this study was to determine the acute effects of a pilates exercise intervention on performance of a lower extremity maximal strength effort. Methods: Ten recreationally trained males between the ages of 18–26 with a minimum of 6-months of resistance training experience and demonstrated proficiency with the deadlift exercise were recruited for this study. Subjects completed 3 visits: the first visit was used to establish a baseline 1RM value for the deadlift while the second and third visits were randomly ordered and involved subjects completing either a 12-minute cycling ergometer intervention at an RPE between 10–12 or a 12-minute Pilates mat-based exercise program prior to repeating the deadlift 1RM test. Independent-sample t-tests were used to compare 1RM scores between the conditions. Results: Mean baseline 1RM deadlift (164.1 kg ± 38.5 kg) was significantly larger (p < 0.001) than the post-cycling 1RM deadlift (157.5 kg ± 36.4 kg) but not significantly different (p = 0.591) than the post-Pilates 1RM deadlift (164.8 kg ± 38.8 kg). The post-Pilates 1RM deadlift was significantly larger (p = 0.001) than the post-cycling 1RM deadlift. Conclusions: Performance of a 1RM deadlift was not positively influenced by a Pilates exercise intervention but was negatively influenced by a cycling intervention. Due to the nature of the baseline assessment a larger volume of deadlift repetitions were completed during this visit than during the intervention visits. The increased volume may have elicited a similar preparatory effect as the Pilates program. The decrease in deadlift 1RM performance following the cycling intervention may be due to fatigue in the lower extremity musculature even though the intensity and duration of the program was low. The results indicate that a Pilates mat-based exercise program is a better choice than a low-intensity aerobic activity to precede a resistance training session involving maximal or near-maximal efforts Practical Applications: Identifying the most effective movement preparation protocol is an important component when designing daily resistance training sessions. The results of this study indicate that a movement preparation protocol incorporating Pilates mat-based exercises will generate a more positive outcome than a low-intensity aerobic cycling protocol when performance of maximal or near-maximal efforts is prescribed for the daily training session.

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44. The Relationship Between the Number of Weekly Practice Hours and Competition Performance by Apparatus of Compulsory Female Gymnasts

A. Russell, H. Williford, G. Schaefer, C. Foo, and M. Esco

Auburn University at Montgomery

Female artistic gymnasts in the United States in levels 4 and 5 are considered compulsory gymnasts. All gymnasts at the same compulsory level perform the same predetermined routines. While the skills and routines for each level are clearly outlined, there are no requirements regarding the appropriate number of training hours per week for gymnasts at a particular level. Thus, the amount of time gymnasts train each week is determined by individual gymnastics clubs, and varies widely from gym to gym. Purpose: The purpose of this investigation was to determine if there is a correlation between number of weekly practice hours (WPH) and competition performance of compulsory female gymnasts on each apparatus: vault (VT), uneven bars (UB), balance beam (BB), and floor exercise (FX). Methods: The 2012 State Championships apparatus scores from 373 level 4 and 5 gymnasts from 4 states who competed in their compulsory championships were randomly selected for data analysis. All scores were obtained from www.mymeetscores.com, a public website that publishes meet results from USA Gymnastics sanctioned events. The weekly practice hours (WPH) for each gymnast were obtained from practice schedules posted on public websites of the gyms that the gymnasts represented at their respective state championships. Pearson product correlation was used to determine the relationship between WPH and each apparatus: VT, UB, BB, and FX. Results: There were very weak correlations found between WPH and VT, UB, BB, and FX (r = −0.14, p ≤ 0.05; r = 0.16, p ≤ 0.05; r = 0.11, p ≤ 0.05; and r = 0.03, p ≤ 0.05, respectively). Conclusions: This study found very weak correlations between WPH and competition performance on each of the apparatus. Therefore, WPH does not appear to be related to performance in compulsory female gymnasts. Practical Applications: Practitioners should be aware of the results of this study when determining weekly practice time for compulsory female gymnasts. The association between WPH and competition performance is small. Further study is needed to investigate the relationship between the number of practice hours and performance outcomes of compulsory female gymnasts.

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45. Deceptive Load Information Does Not Enhance Bench Press Strength Measures

J. Schnaiter1 and T. Piper2

1Ball State University; and 2Western Illinois University

Maximal strength measures are the objective of many strength and conditioning programs. One potential limitation to max strength testing is that participants may not offer maximal effort for various reasons, resulting in sub-maximal measures of strength. Purpose: The purpose of this study was to determine the effects of deceptive feedback on maximal strength during a machine bench press. Methods: Thirty-two recreationally athletes age 19.875 ± 1.621 completed 6 days of maximal bench press testing (non-consecutive). On the first 2 days of testing, participants were tested for true one-repetition maximum (1RM) lifts and given accurate feedback. On testing days 3, 4 and 5, participants were given randomized deceptive feedback in which they were told that the loads were 5% (T-5), 10% (T-10), and 15% (T-15) below the actual weight of resistance for each attempt. To mask the true nature of the study the weight stacks on the machine were concealed and participants were told that this was so that they could focus on proper technique. This deception resulted in the subjects lifting loads which were above what they were told and believed. On the final day of testing (TF) participants were informed that the loads reported during the prior 3 sessions (T-5, T-10, T-15) were inaccurate and that the final test session was critical to the completion of the study. They were then given accurate feedback for the final 1RM trials. No verbal encouragement was given during any of the trials other than the reporting of perceived weights being attempted. After all of the participants completed the 6 days of testing, they were debriefed and told the true nature of this research. The manipulation of the results on T-5, T-10, and T-15 was explained and their results were revealed. Differences were determined using a repeated ANOVA with Bonferroni post-hoc tests (p ≤ 0.05). Results: The average 1 RM scores for the bench press were as follows: TC (178.87 ± 8.13), T-5 (180.84 ± 7.81), T-10 (179.59 + 7.65), T-15 (177.78 ± 7.93), TF (187.00 ± 8.05). 1 RM was significantly different between TC and TF. Conclusions: These findings indicate that deceptive feedback did not increase 1 RM measures on bench press machine, however, when subjects were instructed that their performance was critical to the completion of the study they performed at significantly higher levels than any other trial. Practical Application: The common practice of the bench press may explain why deceptive feedback did not elicit a significant increase in one-repetition maximums. The motivation to perform greater strength measures indicates that some form of psychological manipulation does influence maximum strength for the bench press. When participants are properly motivated they are able to lift significantly more than may be expected.

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46. Comparison of Muscle Activity During the Olympic Deadlift and a Walk-In Deadlift Machine

B. Snyder, S. Senger, and C. Cauthen

University of South Carolina Upstate

Purpose: The deadlift exercise is one of the most effective exercises for developing lower-body strength, but technique errors can lead to low back injuries. For individuals prone to back injuries or for inexperienced lifters, a walk-in deadlift which moves the load to the side of the lifter may be preferable as a “stepping stone” exercise. The purpose of the study was to compare EMG activity and body position of the walk-in deadlift machine and the standard Olympic Deadlift (OD). Methods: Fifteen college-aged resistance trained individuals were recruited. Subjects were classified as High Skilled (n = 8), or Low Skilled (n = 7) based on their current and historical use of the deadlift in training, although all had some training in the lift. Motion capture analysis measured posture and electromyography was used to measure muscle activation while performing 80%3RM of OD and 2 different variations of the walk-in deadlift (WID) machine: 1) WID with the end of the toe aligned with the load and pronated grip (ToePro), and 2) WID with ball of the foot alignment and pronated grip (BallPro). Results: There were no differences in concentric normalized EMG between High Skilled and Low Skilled but in the combined low and high skilled groups, activity of the erector spinae was 27.4% lower (p ≤ 0.05) than ODL during the WID BallPro variation, but was statistically unchanged for the ToePro variation. Quadriceps activity was significantly higher in both WID variations compared with OD (+64.4% for BallPro, and +32.2% for ToePro), while gluteus maximus activity was lower (−36.1% for BallPro, and −36.0% for ToePro). Biceps femoris activity was the same for all exercises. Motion-capture data revealed that during the ToePro lift, the back angle was significantly (plower (more upright posture) than OD at the start (148 ± 2.9 from the right horizontal axis for ToePro vs. 156 ± 3.4 for OD), mid-concentric (133 ± 2.2 ToePro, 137 ± 1.1 OD) and mid-eccentric (128 ± 2.2 ToePro, 133 ± 1.9 OD) phases of the lift. The knee was also more flexed in all phases (81 ± 3.1 vs. 69 ± 3.3 at start, 43 ± 2.2 vs. 21 ± 1.7 mid concentric, (p ≤ 0.05) 52°±2.1 vs. 30 ± 2.2 mid eccentric). These differences were also present for the BallPro lift, with the exception of the knee angle at the start and the back angle for the mid-concentric phase. Furthermore, for both BallPro and ToePro, the hands were significantly closer (p ≤ 0.05) (66% for BallPro, 46% for ToePro) to the knee during the concentric lift compared to the OD, and significantly closer for BallPro (37%) compared to ToePro. No differences in posture were found between High skilled and Low skilled participants. Conclusions: Although differences in posture are not always directly predictive of EMG activity, the results suggest that the WID may be safer for both high and low skilled individuals based on EMG activity of the low back, posture, and position of the load during the lift. Practical Application: Use of the walk-in deadlift machine may prove useful at preventing injuries in novice lifters, although each participant must consider the effect of differences in leg and hip muscle activation on training results when deciding which exercise to use during their workouts.

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47. A Comparison of Autoregulatory Progressive Resistance Exercise vs. Traditional Periodization on Body Composition and Muscular Strength in Older Females

M. Stone,1 C. Foster,2 C. Wilborn,2 and B. Brabham2

1Univeristy of Mary Hardin-Baylor/Human Performance Laboratory; and 2University of Mary Hardin-Baylor

Purpose: While traditional periodized resistance training programs have been studied extensively, a form of periodization termed autoregulatory progressive resistance exercise has limited research regarding its benefits outside the population of college aged athletes. Therefore, the purpose of this study was to determine if a significant difference existed between an autoregulatory progressive resistance exercise (APRE) protocol and a traditional linear periodization (PER) protocol in regards to body composition, muscular strength and muscular endurance in women between the ages of 50–70 year old. Methods: Utilizing a matched pair design, subjects (n = 21, 57.5 ± 5.3 years, 78.83 ± 13.92 kg, BF% 41.5 ± 6.8) performed either an autoregulatory progressive resistance exercise (APRE) protocol or a traditional linear periodization (PER) protocol 3 days per week. At weeks 0 (T1) and 4 (T2) subjects had body composition determined through dual-energy x-ray absorptiometry (DEXA) as well as 1 repetition maximum (1RM) for both the chest press (CP) and leg press (LP). Additionally, subjects completed a repetition to failure test at 75% of their 1RM. Subjects were matched according to body composition and total weight lifted on the CP and LP and then randomly assigned to either the APRE group or the PER group. Baseline analysis revealed no significant differences between the groups on assessed variables (CPMaxkg, p = 0.585, LPMaxkg, p = 0.258, FMkg, p = 0.769, LMkg, p = 0.753, BF%, p = 0.513). Subjects were then required to perform their assigned protocol 3 days a week for 4 weeks. Data were analyzed using an independent samples t-test. Results: No significant differences were observed in any of the assessed variables after 4 weeks of training (CPMaxkg, p = 0.603, LPMaxkg, p = 0.745, FMkg, p = 0.765, LMkg, p = 0.860, BF%, p = 0.420). Conclusions: While the results revealed no significant differences between the APRE and PER groups, participants in both groups did experience increases in muscular strength and endurance, a decrease in body fat percentage, and an increase in lean mass. Practical Application: Today's strength and conditioning professionals are always looking for programs that meet the needs of their athletes and/or clients. Autoregulatory progressive resistance exercise programs allow the athlete/client to have good and bad days and adjusts for how they are performing on any given day. This protocol is another option for those seeking to improve performance and/or function. Acknowledgments: This study was funded by a graduate faculty research grant from the University of Mary Hardin-Baylor.

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48. Assessment of Difference in Perceived Exertion Between Coaches and Players During 1-Week of Pre-Season Training

R. Wilson1 and A. Snyder2

1Dept of Kinesiology and Physical Education, Northern Illinois University; and 2University of Wisconsin–Milwaukee

During practices coaches evaluate the level of exertion experienced by their players to determine when they need to take breaks and adjust the intensity level of drills within the session, and to modify the planned intensity level of future sessions. This evaluation is typically achieved through qualitative means. The accuracy of these evaluations depends on the perceptive skills of the coach, which can be further mediated by the years of coaching experience. To assess how well the coach is able to evaluate the level of exertion that the players have undergone during a training session a common measure needs to be used. Purpose: The purpose of this study was to determine the agreement between the coach and the players' in their perception of exertion during multiple training sessions using a common measure of perceived exertion. Methods: Twenty-two (n = 22) college-level male soccer players and the assistant coach provided their perceived exertion level for the first week of training during a pre-season training period. A previously used modified version of the Borg Criterion-Reference 10 Rating of Perceived Exertion (RPE) scale was used as the objective measure. After 13 of the 14 training sessions, players provided their RPE score for the whole session. RPE scores were obtained within 10 minutes after the conclusion of the training session. The coach provided his RPE score for the players' for the whole training session without bias from the players. The scores were analyzed using a paired sample t-test to determine if they were different for each session as only the session comparisons were appropriate and not those across the training week (p ≤ 0.05). Results: For 10 of the 13 training sessions, the ratings of exertion for the session were significantly different between the players and the coach (Table 1). In 5 of the training sessions, the coach provided a higher rating than the players did. In 5 of the training sessions, players provided higher ratings than the coach did. Discussion: The amount of agreement between the coach's and the players' level of perceived exertion was very low and the tendency of the error between the scores was inconsistent even though both the players and the coach were familiar with the RPE scale. Practical Application: As the RPE scale has been shown to be a reliable measure of physiological exertion during intermittent training sessions, these data indicate that there is more disagreement than agreement between a coach's perception of the exertion on his players and the players own perception of the exertion for the observed training sessions. Therefore, greater discussion of exertion expectation and/or more practice in using a scale may be necessary to track training intensity in this manner.

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49. Standardization of Individual and Series Elastic Band Resistance Properties With Custom Designed Slide Tension Assembly

J. Anning, C. Hughes, M. Calhoun, D. Tommarello, and B. Richardson

Slippery Rock University

Even though many coaches and trainers use elastic bands as a form of resistance during acceleration training, no research has gone into developing a reliable method to quantify the resistance offered from these bands. Purpose: The purpose of this study was to quantify the resistance of individual and series elastic bands using a custom designed slide assembly. Methods: Four different colors of bands (Flexbands, Speed and Explosion, Stow, OH) were individually tested: (a) micro (RED), (b) monster mini (BLACK), (c) light (PURPLE), and (d) average (GREEN). Each band was tested individually at regular intervals of 1 inch up to 150% of its resting length based on recommendation by the manufacturer. The elastic band chains were created by tying 4 bands of the same color in a series. The band was then secured to the waist of the subject who then walked forward to the 11 foot starting position so the slack was removed from the band. Static tension for the series elastic bands was then measured at 1 foot intervals within the resisted acceleration training range (11–21 feet). A custom designed slide tension assembly (Sweeney Automation, Baltimore, MD) was used to record band tension as a function of elongation length. Simple linear regression was used to predict elastic band tension from 1 inch intervals for each band color. Results: Strong linear relationships (p < 0.01) were found for each individual and series band color. Individual tension (lb) was predicted using the following regression equations (length = in): (a) RED = 0.74 (length) + 1.51; (b) BLACK = 1.15 (length) + 1.77; (c) PURPLE = 1.67 (length) + 3.08; and (d) GREEN = 2.79 (length) + 4.78. Series tension was predicted using the following regression equations: (a) RED = 1.57 (length) + 3.27; (b) BLACK = 2.47 (length) + 4.6; (c) PURPLE = 3.39 (length) + 6.67; and (d) GREEN = 5.93 (length) + 10.07. Conclusions: Based on the results, individual and series tension-displacement patterns have been quantified. Practical Application: The standardization of individual and series elastic band resistance properties establishes a foundation for future studies exploring how these bands could be used to provide resistance during acceleration training. Acknowledgments: This study was supported by the Slippery Rock University Faculty/Student Research Grant Program.

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50. Gender Comparisons of Muscle Activation Patterns of the Biceps Femoris, Rectus Femoris and Gluteus Maximus During a Glute Bridge Exercise

H. Bradburn,1 R. Dudley,2 G. Noffal,1 and S. Lynn1

1California State University, Fullerton; and 2California State University Fullerton

Introduction: The gluteus maximus is one of the largest and most powerful muscle in the human body and these morphological features are in direct correspondence to its function; therefore improving the function of this muscle may aid in greater efficiency of movement patterns. Previous research proposed that gluteus maximus weakness has been associated with various lower extremity injuries. Females have shown greater susceptibility to lower extremity injuries, with a majority being quadriceps dominant compared to males in various dynamic sporting activities. However, it has not been established whether there are gluteus maximus, hamstring and quadriceps differences between genders in an isolation exercise. Purpose: The purpose of the study was to assess whether muscle activation patterns in the lower extremities differ between males and females during an isolation exercise. Methods: Twenty-one healthy females (age: 22.73 ± 3.19 years; height: 1.62 ± 0.06 m; mass: 59.82 ± 9.9 kg) and 30 healthy males (age: 22.74 ± 2.24 years; height: 1.77 ± 0.06 m; mass: 84.83 ± 16.54 kg) participated in this study. Electromyography (EMG) was collected from the gluteus maximus, biceps femoris and rectus femoris on the dominant lower extremity while subjects performed the glute bridge exercise, at a sampling rate of 1000 Hz. The following muscle ratios: gluteus maximus to biceps femoris (GluteMax/Hamstring); biceps femoris to rectus femoris (Hamstring/Quadriceps); gluteus maximus to rectus femoris (GluteMax/Quadriceps) were calculated. Results: Between subjects MANOVA revealed a significant effect of gender (p ≤ 0.05). Males illustrated significantly greater GluteMax/Hamstring ratio than females in the glute bridge exercise (p = 0.025). The GluteMax/Quadriceps ratio was significantly greater for males compared to females during the task (p = 0.015). No differences were observed, however, in the Hamstring/Quadriceps ratio between genders. Conclusions: These findings may have potentially occurred due to males predominantly activating the gluteus maximus or females increasing the hamstring activation to complete the hip extension movement; suggesting an alternative strategy between genders. The differences in GluteMax/Quadriceps ratio may have been a result of males displaying greater gluteus maximus activation while females utilize greater quadriceps activation. This may have clinical implications related to greater quadriceps activation, placing females at greater risk of injury, by potentially applying strain to anterior cruciate ligament in dynamic movements, as there is greater anterior contraction unopposed by weaker posterior muscles. Practical Implication: Rehabilitation and training in female athletes should pay special attention to focus on exercises that target greater levels of gluteus maximus activity, as this is crucial to aid the correct muscle recruitment patterns to conduct movements efficiently, assist stability and reduce injury risk. Use of the gluteus maximus should be encouraged to relieve stress on the smaller bicep femoris muscle, caused glute amnesia, which is initiated by sedentary lifestyles.

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52. Between Session Reliability of the Turning Point Core Trainer as a Measure of Shoulder Hip Separation Angle and Angular Velocity

J. Brown,1 M. Waller,2 P. Eisenman,1 and C. Hicks-Little1

1University of Utah; and 2University of Saint Francis

Introduction: Shoulder Hip Separation Angle (SHSA) has been determined to be an important factor regarding performance in rotational sports such as golf and baseball. To date 3-dimensional motion capture analysis has been used to measure SHSA; however, due equipment costs and lengthy time periods to analyze measurements it is not practical for sports conditioning coaches (SCC). Although 3-dimensional motion capture analysis is recognized as the gold standard, a more economical and time efficient tool is needed to evaluate such measurements. The Turning Point Core Trainer (TP) is a device designed to measure SHSA, Shoulder Angular Velocity (SAV), and Hip Angular Velocity (HAV); however, data regarding reliability of this tool is lacking. The purpose of this study was to examine between session reliability of the TP as a measure of SHSA, SAV, and HAV. Methods: Fifty-eight healthy individuals from the University of Utah volunteered for this study (male = 33, female = 26, age 24.85 ± 4.37 years, height 1.72 ± 0.09 m, weight 70.74 ± 12.89 kg, BMI 23.78 ± 2.95 kg/m2). This study was approved by the Institutional Review Board at the University of Utah. Each participant completed three 30 seconds trials on 2 separate testing days using the TP with zero resistance and no forward incline. A one minute rest period separated each trial. Participants were asked to return to the lab for the second testing session within 3–14 days. SHSA is the difference between the upper torso and hip about the body's y-axis and was recorded in degrees. In addition, the TP was used to measure SAV and HAV and was recorded in (°-s−1). All angular velocities were recorded around the y-axis. Maximal SHSA, SAV, and HAV for both directions were used for analysis. Intraclass correlations (ICC) were used to examine reliability between testing sessions. In addition, paired t-tests were used to examine differences in SHSA, SAV, and HAV between testing sessions. Statistical significance was set at p ≤ 0.05. All data was analyzed using PASW Statistical software 18.0 (IBM Inc., Chicago, IL). Results: The results revealed excellent ICC, and no significant differences between testing days (Table 1). Conclusions: These results support the hypothesis that the TP has excellent test-retest reliability and support its use for assessing SHSA, SAV, and HAV. Practical Application: These findings support test-retest reliability using the TP; however, future studies should examine the validity of the TP. Acknowledgments: We would like to express our gratitude to BioTechnology for use of the Turning Point Core Trainer.

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53. Relationship Between Rotational Kinematics of the Pelvis and Thorax Segments and Club Head Velocity in Elite Golfers

J. Charles, G. Noffal, S. Lynn, K. New, and B. Frazier

California State University, Fullerton.

Proper proximal to distal sequencing has been shown to be an important factor in golf for producing high club head velocities. Since these rotations originate at the pelvis and travel up to the thorax, it has been suggested that increasing the range of motion (ROM) of these segments will lead to higher segmental velocities, which will translate to higher club head velocities. Although a higher ROM may lead to higher segmental velocities, the timing and coordination of these segmental velocities, not just the magnitude, likely play a role in increasing clubhead velocity. Purpose: To analyze the effect of downswing range of motion of the pelvis and thorax segments on the velocity of those segments, as well as clubhead velocity. Methods: Twenty high-skilled golfers (23.5 ± 5.32 years, 1.82 ± 0.05 m, 77.7 ± 7.0 kg), maintaining a handicap less than 5, completed 5 golf swings each. A motion capture system was used to identify swing kinematics. The ROM and the downswing velocity of the pelvis segment and thorax segment were calculated for each golf swing. Along with this, the clubhead velocity at impact was recorded for each trial using a ball flight monitor. A bivariate correlation was used to determine if a correlation existed between the downswing ROM of the pelvis and thorax, the downswing velocities of these segments, and clubhead velocity. Results: Pearson correlation coefficients revealed several significant correlations between variables. Among these were: (a) a positive relationship between pelvic ROM and pelvic downswing angular velocity, (b) a negative relationship between pelvic ROM and clubhead velocity, (c) a positive relationship between thorax ROM and thorax downswing angular velocity, and (d) a negative relationship between thorax ROM and clubhead velocity (Table 1). Discussion: The results of the present study show that as ROM increases, the clubhead velocity decreases. This suggests there are more variables involved in increasing clubhead speed than just increasing the range of motion. Previous research has shown that the rate of acceleration and deceleration of these segments, along with when the peak velocity occurs relative to impact are important factors to consider when attempting to increase clubhead velocity. Practical Application: These findings may provide strength and conditioning specialists with insight regarding the fact that increasing clubhead velocity cannot simply be accomplished by stretching to achieve a higher ROM in the pelvis and thorax segments. The focus needs to include training segment acceleration and deceleration along with timing and coordination of segment rotations as well. It is worth noting that the present study used young, elite golfers; if elderly participants had been used it is possible a positive correlation would have existed between segmental ROM and clubhead velocity, and the specialist should indeed focus on improving ROM.

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54. Relationships Between Medial Gastrocnemius and Achilles Tendon Architecture and Jump Performnce in Rugby League Players

P. Comfort, A. Regan, and J. McMahon

University of Salford

Numerous studies have identified relationships between athletic performance and muscle-tendon architectural properties. Lateral gastrocnemius thickness and Achilles tendon (AT) length have been shown to be moderately related to jump performance and rate of force development (RFD) in trained males. The medial gastrocnemius (MG), however, is the most frequently studied muscle with regard to fascicle-tendon behavior during stretch-shorten cycle (SSC) exercise and has been shown to be of great importance to SSC function. Purpose: The purpose of this study was to identify and compare the relationships between MG and AT architecture and peak power, during the squat jump (SJ) and countermovement jump (CMJ). Methods: Twenty one, well trained professional rugby league players (age 24.3 ± 2.6 years, height 181.7 ± 5.7, body mass 94.4 ± 9.1 kg) performed 3 SJ and 3 CMJ on a force platform to determine peak power using a forward dynamics approach. The best performance of each jump was used for further analysis. Ultrasound images were recorded using a 7 MHz linear array ultrasound probe capturing in B-mode, with a scanning depth of 60 mm. To determine MG fascicle length, pennation angle and thickness the probe was positioned at the mid-portion of the MG muscle belly and was orientated in the same plane as the MG fascicles. AT thickness was measured 2 cm proximal to the AT insertion on the calcaneus and AT length was calculated as the distance between the AT insertion and the MG muscle-tendon junction. Results: Intraclass correlation coefficients showed a high reliability (r ≥ 0.83, p < 0.001) for power during jump performances and muscle-tendon architecture (r ≥ 0.94, p < 0.001). Moderate correlations were observed between SJ power and MG fascicle length (r = 0.42, p < 0.01; r2 = 0.18) and pennation angle (r = −0.43, p < 0.01; r2 = 0.18) and CMJ peak power and AT length (r = 0.43, p < 0.01; r2 = 0.18) (Table 1). Conclusions: AT length is more closely associated with peak power during the CMJ compared to the SJ, whereas MG fascicle length and pennation angle are more closely associated with peak power during the SJ. Practical Application: These findings highlight relationships between peak power and lower leg muscle and tendon architecture during jump performance, similar to previous research. The differences in relationships between the CMJ and SJ may be attributable to the role of the SSC in each exercise. Acknowledgments: Thank you to Wigan Warriors Rugby League Team.

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55. Dynamic Postural Stability Positively Altered Following Participation in an Injury Prevention Program

M. Crawford,1 C. McCrory,1 N. Cortes,2 and E. Greska1

1University of West Florida; and 2George Mason University

Lower extremity injury prevention programs have shown results of their success, however, there is little data that describes the effects on balance and control when participating in such training programs. Purpose: To determine the effects of a neuromuscular training intervention (NTI) on the performance of the Star Excursion Balance Test (SEBT). Methods: Participants included 15 Division I female soccer players (19.6 ± 1.0 years, 1.67 ± 0.05 m, 63.1 ± 5.7 Kg), free of lower extremity injury at the time of participation. A motion analysis system, comprised of 8 cameras and 2 force plates, was utilized to capture biomechanical data. Laboratory testing required the participant to perform the SEBT while standing on a single force plate, with 3 valid trials for each of the anterior (ANT), posterior-medial (PMD), and posterior-lateral (PLT) directions using both legs (Right Leg, RL; Left Leg, LL). Upon completion of the initial laboratory tests, participants partook in NTI. The 10-week on-field training program was integrated into normal team practice, and consisted of plyometric and agility drills, focusing on proper movement patterns. Post-NTI was identical to pre-NTI procedures. Each SEBT trial was examined from initial toe-off of the reaching foot to the returning touchdown. Bilateral peak mean variables of interest included reach distance, center of pressure (COP), and joint rotations of the hip, knee, and ankle. Joint rotations included flexion (FLX), extension, abduction (ABD), adduction (ADD), internal rotation (IR), and external rotation (ER). For comparative analysis, reach distances were normalized to the participant's respective leg length. Repeated measures ANOVAs were used to evaluate the effects of training (pre to post), with an a priori alpha level set at 0.05. Results: From pre-to post-training, the RL ANT direction displayed significant increases in anterior COP (p = 0.048), and knee IR (p < 0.001); as well as significant decreases in knee ADD (p = 0.002), and knee ADD/ABD range (p = 0.033). No significant differences were noted for LL in the ANT direction. For PMD direction, the LL exhibited significant decreases in anterior COP (p = 0.038) and hip IR (p = 0.048), and an increase in anterior/posterior COP range (p = 0.041). The RL for the PMD direction significantly increased in anterior/posterior COP range (p = 0.032), hip ER (p = 0.014), knee ABD (p = 0.045), and decreased in medial/lateral COP range (p = 0.030), hip IR (0.014), knee ADD (p = 0.035), and ankle IR/ER range (p = 0.018). In PLT direction, the LL displayed significant increases in reach distance (p = 0.043), anterior COP (p = 0.001), and hip ER (p = 0.012), and decreases in posterior COP (p = 0.011), and hip IR (p = 0.010). The RL for the PLT direction significantly increased in anterior COP (p = 0.022), hip ABD (p = 0.022), hip ADD/ABD range (p = 0.002), hip ER (p < 0.001), hip IR/ER range (p = 0.003), knee FLX (p = 0.045), and knee IR (p = 0.026), and decreased in posterior COP (p = 0.033), hip IR (p = 0.008), knee ADD (p = 0.003), knee ADD/ABD range (p = 0.003), and knee ER (p = 0.002). Discussion: Coupling of alterations in COP and joint rotations demonstrates an increased level of dynamic postural control after NTI participation. Such increases in dynamic postural control may help expound upon the mechanisms that facilitate the reduction in lower extremity injury incidence when participating in injury prevention programs. Practical Application: The functionality of an NTI demonstrates the ability to not only reduce injury occurrence but also the ability to improve physical performance.

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56. Acute Effects of Assisted Jumping on Jump Performance

D. Dunnick,1 T. Beaudette,1 L. Brown,2 J. Coburn,1 and S. Lynn1

1CSU Fullerton Center for Sport Performance; and 2California State University, Fullerton

Introduction: Vertical jump (VJ) performance plays an important role in various sports. There has been conflicting research investigating assisted jumping as means to enhance VJ. It is hypothesized that assisted jumping may lead to an acute increase to VJ performance. Purpose: The purpose of this study was to investigate the acute effects of assisted jumping on body weight VJ performance. Methods: Nine NCAA collegiate women's volleyball players (19.11 ± 1.05 years; 175.99 ± 7.52 cm; 75.47 ± 10.88 kg) completed 2 experimental conditions (bodyweight [BW] and assisted jumps [AJ]). Following each condition, participants performed 3 bodyweight countermovement VJ separated by 15 seconds rest. During AJ participants wore a climbing harness with elastic cords attached to their hips, then stretched to the ceiling by a rope. In both conditions participants performed 5 plyometric countermovement VJ with either 0% bodyweight reduction or 40% bodyweight reduction depending on the trial. Following both conditions, participants rested for 1 minute then performed 3 individual bodyweight countermovement VJ separated by 15 seconds rest. Jump height, relative delta GRF, and take off velocity were measured using an AMTI force plate sampling at 1000 Hz. Results: There was no main effect for condition. Difference in jump height (C = 33.85 ± 4.56 cm, BW = 32.06 ± 8.45 cm, AJ = 34.10 ± 4.99 cm), relative delta GRF (C = 14.4 ± 3.95 N/kg, BW = 14.77 ± 3.32 N/kg, AJ = 14.13 ± 2.79 N/kg) and take off velocity (C = 2.51 ± 0.02 m/s, BW = 2.53 ± 0.23 m/s, AJ = 2.52 ± 0.21 m/s) were not statistically significant. Conclusions: These results suggest that the assisted jumping stimulus was not strong enough to elicit differences in jump performance. Perhaps a greater stimulus due to greater bodyweight reduction may have resulted in faster take-off velocity which could translate to increased bodyweight jump performance. Additionally, the use of a harness during assisted jumping may have altered the subjects jumping mechanics leading to an unnatural feeling jump. Practical Application: These findings do not support acute increases in jump performance post assisted jumping in experienced jumpers a 40% bodyweight reduction. The use of experienced vs. inexperienced participants as well as greater bodyweight reduction may have an effect on the acute implementation of assisted jumping, and should be investigated further.

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57. Validity of the MAD MAXX Power Reading for Firing out of the Positional Stance for American Football Players

H. Jahandar, B. Mann, J. Stoner, and T. Guess

University of Missouri

The speed and power of offensive and defensive lineman is key for the success of a football team. The ability to measure the change in abilities for a sports specific movement like firing off of the ball is crucial to understanding the effectiveness of the strength and conditioning program. The MAD MAXX (Just Better Sports by Shoot-A-Way—Upper Sandusky, OH) is essentially an immovable tackling dummy which purportedly measures the power of the athlete when driving off of the ball as well as their reaction time. It is unknown, however, how the power is measured and if the power reading is actually accurate at all. Purpose: The purposes of this study were to determine the validity of the power reading of the Mad Maxx. Methods: A 10 g ENDEVCO Model 7596A VALULINE accelerometer (Meggitt Sensing Systems—Irvine, CA) is attached to the end of the sliding bar in the MAD MAXX machine. The signal from the accelerometer is used to find the time that impact starts and the time that the dummy reaches the end of the path. In each trial, the signal from the accelerometer is recorded and the value from the MAD MAXX machine is logged. The signal is then filtered using LabVIEW software (National Instruments Corporation—Austin, TX) to find the time interval during which the energy transfer occurs in order to measure the power in each trial. The weight of the dummy and the length of the path that dummy travels after the impact have been measured in advance to calculate the energy that is transferred during the impact. Eleven players, 5 offensive-line players and 6 defensive-line players were involved in the experiment. One of the defensive-line players attempted 9 times and charged the dummy from a 2-foot line in front of the machine. The rest of the players made 3 to 5 attempts individually. Results: The results indicate that there is a significant difference between the values recorded by MAD MAXX and the ones calculated by the method. The data recorded by the accelerometer for the 9-attempt defensive-line player had a mean of 540.9 and a standard deviation (SD) of 33.0 while the numbers logged by MAD MAXX had an average of 764.0 and a SD of 185.2. The t-test performed between these 2 groups results in a p value of 0.006. The average power recorded by MAD MAXX was 680.7 and 551.4 for defensive-line and offensive-line players respectively. The average power calculated by the accelerometer was 542.2 and 502.3 watts for the same groups. Both the MAD MAXX values and the power measurements indicate higher power values for defensive-line players compared to offensive-line players. For these players, data from the MAD MAXX machine have average values ranging from 435.2 to 795.2 for each player with a high standard deviation ranging from 61.6 to 289.8 (average 147.0). However, the power calculated by the accelerometer shows more consistency; the average values range from 463.8 to 580.7 with a narrower standard deviation ranging from 19.7 to 68.6 (average 38.8). The high standard deviation for each player power measurements in MAD MAXX and inconsistency between the MAD MAXX values and calculated power values for each trial suggest that MAD MAXX values cannot be used for tracking the athletes' performance or deciding on training routines. Conclusions: There was a significant difference between the 2 measurement systems. The Mad Maxx demonstrated a much higher standard deviation (147.0) compared to the accelerometer data (38.8W). Practical Application: Strength and conditioning practitioners should not rely on the MAD MAXX to determine power outputs for an athlete executing a firing off maneuver, as the data was found to be neither valid nor reliable. Practitioners wanting this data may need to rely on other mechanisms to get this information.

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58. Lateral Squats Significantly Decrease Sprint Time in Collegiate Baseball Athletes

M. Jones,1 B. Thompson,2 and T. Dorian2

1George Mason University; and 2Springfield College

Purpose: Lateral movement is commonly used in the sport of baseball in reaction to a stimulus. Post-activation potentiation, in the form of complex training, has been shown to elicit greater lower body power production in explosive movements when heavy strength movements are performed prior. The purpose of the current study was to examine the acute effect of lateral squats on lateral movement and sprint time. Methods: Male, NCAA Division III baseball athletes (n = 12, mean ± SD: 18.9 + 1.2 years, 176 + 6.6 cm, 79.9 + 10.9 kg) with >1 year of formal strength training participated in this repeated measures crossover design that consisted of 3 sessions each separated by 3 days. Session 1 consisted of familiarization with the 10-minute supervised standardized warm-up, lateral squat (LS) technique, and the lateral movement-into-a-sprint test (LMS). All were proficient in the LS and performed it regularly in training. Subjects were then randomly assigned the order of testing protocols for sessions 2 and 3. The session 2 protocol consisted of the warm up followed by either sitting for 1-minute (no-LS) or performing the LS for 1 x 5 repetitions @85% 1RM for each leg. Next, 4 minutes of walking preceded the LMS, which consisted of leading off of a base and waiting for the visual stimulus from a light emitting diode. In reaction to the visual stimulus, subjects exerted maximal effort while moving to the right by either pivoting or crossing over the foot and sprinting for 10 yards (yd). In session 3, the subjects switched protocols (LS, no-LS). Dartfish software (Dartfish Inc., USA) was used to assess foot contact time (FCT), stride frequency (SF), and stride length (SL). Infrared timing (Brower Timing Systems, USA) was used to measure 10-yd sprint time (ST). Repeated measures ANOVA was used to analyze differences across conditions for FCT, SF, SL, and ST. Significance (p ≤ 0.05) is reported. Results: No differences were observed between the LS and no-LS conditions for FCT (p = 0.70), SF (p = 0.28), or SL (p = 0.79). A significant difference for ST (p = 0.03) did exist between LS (1.85 ± 0.09 seconds) and no-LS (1.89 ± 0.10 seconds). The FCT and SL of the first stride was significantly (p < 0.001) less than the second stride. The SF and ST for segment 6–10 yd was significantly (p < 0.001) less than the 1–5 yd segment. Conclusions: Previous research findings have demonstrated improved sprint times following single joint or isometric strength exercise. The effect of multi-joint, dynamic strength exercise on sprint times has been understudied. Results from the current study support the use of dynamic lateral squats for performance enhancement prior to performing a lateral movement into a 10 yd sprint. Practical Application: Complex training, in the form of lateral squats, paired with a lateral movement-into-a-sprint may provide relevant sport-specific training for baseball through improved speed during base running.

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60. Validity and Reliability of Hand and Electronic Timing for 40-YD Dash Times in College Football Players

B. Mann,1 D. Mayhew,2 P. Ivey,1 and S. Bird1

1University of Missouri; and 2Truman State University

The 40-yd dash is the premier event for evaluating sprint speed among football players at all competitive levels. While professional players are timed exclusively with an electronic system, college and high school players may be timed electronic systems or by individuals with varying levels of experience using hand-held stopwatches. Some question remains on the validity of hand timing, as well as a lack of reliability assessment of each method. Some controversy appears to exist concerning the difference between these 2 methods, as well as a lack of reliability assessment of each method. Purpose: The purposes of this study were to evaluate the validity of hand timing when compared to electronic timing and to assess the reliability of both hand and electronic timing for the 40-yd dash among college football players. Methods: NCAA Division I college football players (n = 47) were measured for 40-yd dash at the end of a winter conditioning period. All trials were performed on an indoor artificial turf. Players ran 2 trials that were timed electronically using a touch pad start and infrared beam stop. Each trial was also timed by 2 experienced (ET) and 4 novice timers (NT) using hand-held stopwatches. Results: There was no significant difference (p = 0.93) between trial 1 (5.12 ± 0.37) and 2 (5.11 ± 0.36) timed electronically. One NT had a significantly slower time recorded for the second trial than the first trial; otherwise there was no significant difference between trial 1 (4.92 ± 0.34 seconds) and trial 2 (4.92 ± 0.34 seconds) for the other NT. Reliability for electronically timed trials (ICC = 0.995) was significantly higher than for hand timed trials (ICC = 0.987). The average of all hand timing (4.89 ± 0.34 seconds) was significantly faster in all cases than electronic time (5.12 ± 0.36 seconds) by −0.23 ± 0.05 seconds. Smallest worthwhile difference for electronic timing to indicate a meaningful gain from training would be an improvement greater than 0.07 seconds. The smallest worthwhile difference for hand timing would be an improvement of 0.11 s. Conclusions: Hand timing in the 40-yd dash is typically 0.23 seconds faster than electronic timing in college football players regardless of the experience of the timers. A 1.4% improvement in electronically timed 40-yd dash would indicate a meaningful gain from training, while a 2.2% improvement would be required to show meaningful gain when using hand timing. Practical Application: Electronic timing of the 40-yd dash is the most accurate method of evaluating sprint speed in college football players. Hand-timing may be faster than electronic timing by a value equivalent to a normal individual's reaction time.

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61. Validity of the Schultz Slam Test (SST) as a Measure of Core Power in Collegiate Football Players

D. Schultz,1 A. Dandas,2 A. Petersen,1 T. Koesterer,3 J. Ortega,1 and T. Manos1

1Humboldt State University; 2Lewis & Clark University; and 3Cortland University

Most power sports, such as football, require the use of anaerobic metabolism for a majority of ATP production. Tests currently being used to measure core performance (e.g., sit ups, McGill protocol, and explosive throw tests) are endurance based or require a single maximum burst of energy; none of these tests correlate well to football performance measures. Purpose: To evaluate the validity of a newly designed core power test (i.e., the Schultz Slam Test [SST]) as a measure of core performance in American football players. Reliability, as well as convergent, content and divergent groups' validity were assessed. Methods: Collegiate Division II redshirt players (N = 22; height 185.0 ± cm, mass 102.6 ± kg) had core power measured using the SST and a 60-s maximum sit-up test (with a built-in 30-s test), and core endurance measured using the McGill protocol (McGill, 2007). The SST involved 10 repetitive slams of a 30-lb medicine ball to the ground for time; Standard sit up test and the McGill protocols were used. A standardized testing battery for athletic performance (3-repetition maximums for the power clean, back squat, and bench press, as well as vertical jump height, expressed as absolute values as well as relative to body weight) was completed to assess convergent validity of the core tests. To establish content validity, 7 strength and conditioning coaches (>5 years of football experience) were asked to view a video of the core tests and then complete a questionnaire with items relating to specificity and practicality of the tests. To establish divergent groups' validity, the SST scores of college-level players were compared with 20 high school football players scores. Results: The SST was a reliable test in colligate (r = 0.852, p < 0.0001) and high school players (r = 0.941, p < 0.0001). The only significant correlation between SST and football performance was squat relative to body weight (1.63 ± 0.26; r = −0.505). No significant correlations between athletic performance and sit-ups were found. The McGill protocol best related to athletic performance. The McGill right lateral hold was significantly correlated with relative power clean score (1.20 ± 0.18; r = 0.680), relative squat (1.63 ± 0.26; r = 0.708) and vertical jump height (27.61 ± 2.92 in; r = 0.515). The McGill left lateral hold was significantly correlated with the relative power clean (1.20 ± 0.18; r = 0.773), relative squat (1.63 ± 0.26; r = 0.801) and vertical jump height (27.61 ± 2.92 in; r = 0.520). The total McGill was significantly correlated with the relative power clean (1.20 ± 0.18; r = 0.518), and relative squat (1.63 ± 0.26; r = 0.477). The McGill extension was significantly correlated with absolute bench press (133.71 ± 27.91; r = −0.468). Coaches believed that the SST was the most sports-specific test and the McGill protocol was the most practical test. The collegiate-level players' SST times were significantly faster than high school players (t[40] = 6.70, p = 0.000). Conclusions: Validity of the SST was supported by establishing content and divergent groups' validity, yet convergent validity of SST was not shown. The McGill test better related to football performance measures when compared to sit up and SST measures. Practical Application: Although the SST failed to relate to football performance, the McGill test results suggest that core rigidity may be required to transfer of power in football.

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62. The Effect of Ultra-Endurance Cycling in Hot Environment on TH2 Cytokine

H. Luk,1 D. Levitt,1 A. Duplanty,1 R. Budnar, Jr.,1 A. Fernandez,1 T. Layman,1 A. McKenzie,2 E. Lee,2 L. Armstrong,2 B. McFarlin,1 D. Hill,1 and J. Vingren1

1University of North TX; and 2University of Connecticut

Ultra-endurance cycling under extreme hot ambient temperature imposes transient physiological stress, resulting in changes in the body internal milieu including activation of T helper cell 1 (TH1) and T helper cell 2 (TH2). The balance between the pro- (TH1) and anti-inflammatory (TH2) cytokines is important in regulating the inflammatory response and facilitating recovery after exercise. Only limited attention has been given to the anti-inflammatory cytokines response to exercise in a hot environment. Purpose: We sought to describe the influence of completing 164 km road cycling under moderate to high heat exposure (WBGT: 23.9–36.2 °C) on anti-inflammatory cytokines. Methods: Forty-one experienced cyclists (38 men and 3 women; 49.4 ± 8.6 years; 83.0 ± 14.6 kg; 176.1 ± 7.2 cm; 19.7 ± 6.5% body fat) participating in the August 2013 Hotter’N Hell Hundred ride in Wichita Falls, TX were recruited. Participants completed a 164 km bicycle ride in a hot environment (WBGT: 31.4 ± 3.8 °C: max: 36.1 °C). Blood samples were collected within the 2 hours prior to the ride (PRE, 0500–0700 h) and immediately after event completion (POST). Serum was analyzed for TH2 cytokines: interleukin (IL)-4, IL-5, IL-7, IL-10, and IL-13. Results: Anti-inflammatory cytokines IL-4 (PRE: 1.10 ± 0.48; POST: 0.99 ± 0.55 pg·ml−1) and IL-13(PRE: 0.67 ± 0.45; POST: 0.61 ± 0.44 pg·ml−1) decreased significantly; whereas, IL-10 (PRE: 1.19 ± 0.45; POST: 1.64 ± 0.58 pg·ml−1) and IL-7 (PRE: 0.90 ± 0.27; POST: 1.00 ± 0.29 pg·ml−1) increased significantly in concentration. No change was observed for IL-5 (PRE: 0.3 ± 0.03; POST: 0.3 ± 0.3 pg·ml−1; p = 0.24) from PRE to POST. Conclusions: Ultra-endurance cycling under hot ambient temperature reduced [IL-4] and [IL-13], which indicate a decrease in the signal for mast cell activation, since their function is to promote an Ig class switch to IgE. Meanwhile, an increase in [IL-10] and [IL-7] was found which suggests an inhibition of macrophage function and pro-inflammatory cytokine release. Practical Application: In order to heal from ultra-endurance exercise, pro- and anti-inflammatory cytokines orchestrate the immune-mediated recovery process. The finding of a reduced anti-inflammatory response suggests that consumption of immune suppressive medication, such as NSAIDs, should be avoided in conjunction with ultra-endurance cycling under extreme hot ambient temperature to prevent a potential exacerbation of immune suppression and resulting prolonged recovery.

Friday Podium Presentations

Friday, July 11, 2014, 8:30 AM–8:45 AM

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1. Adenosine Tri-Phosphate's Effects on Power, Reaction Time, and Muscle Excitability Following Repeated Sprinting Bouts

R. Lowery,1 J. Rauch,2 S. McCleary,2 S. Weiner,1 J. Ormes,1 K. Shields,1 M. Sharp,1 J. Joy,1 J. Georges,1 and J. Wilson1

1University of Tampa Human Performance Lab; and 2University of Tampa

*Award Eligible—Master's Student Research Award for an outstanding podium abstract presentation.

Adenosine-5'-triphosphate’s (ATP) role as the primary intracellular energy source for body tissues is well established. One extracellular-mediated function of ATP includes the modification of muscle excitability (i.e., increasing skeletal muscle calcium permeability and blocking chloride efflux) and vasodilation. Purpose: To conduct a pilot study to investigate the effects of ATP supplementation on the ability to sustain power output, reaction time, and muscle excitability during and following a repeated sprint bout. Methods: Ten NCAA National Championship baseball athletes were recruited for this study. A double-blind, placebo controlled trial consisting of individuals either consuming 400 mg/d of PEAK ATP (TSI, Missoula, MT) or 400 mg/d of a placebo was conducted. Wingate peak and average power and electromyography determined muscle activation/excitability were assessed on day 0 and on day 15 after 2 weeks of supplementation. Vertical jump power and reaction time was taken immediately prior to and following the sprinting bout on day 0 and day 15. Results: Vertical jump power decreased from pre to post sprinting in the placebo (−280.8 ± 124.8 watts), but not PEAK ATP condition (+44.4 ± 60.7, Group × Time, p ≤ 0.05). Wingate power from sprint 1 to 10 on day 15 tended to be greater and the reaction time tended to be faster in the ATP compared to the placebo condition, (Group × Time, p = 0.1). Conclusions: The results of this pilot study suggest that peak ATP supplementation can prevent declines in dynamic power output following an intermittent sprinting bout and warrants further study. Practical Application: Athletes looking to maintain power output during exhausting, intermittent events such as occurs during hockey, soccer, or football games may benefit from supplementing with ATP daily.

Friday, July 11, 2014, 8:45 AM–9:00 AM

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2. Similar Improvement in Sprint Performance Following Sprint Training With vs. Without Ball Carry in Rugby Players

L. Seitz,1 M. Barr,2 and G. Haff2

1Centre for Exercise and Sport Science, Edith Cowan University; and 2Edith Cowan University

*Award Eligible—Doctoral Student Research Award for an outstanding podium abstract presentation.

Enhancing sprint performance is a fundamental component of performance required for success in many individual and team sports such as American football, rugby league and rugby union. Furthermore, sprinting with a ball in hand (ball carry) is of importance for rugby players since scoring a try is associated with players sprinting or accelerating towards the try line while carrying the ball. However, to our knowledge, no attempt has been made to determine the effects of sprint training with ball carry on the sprint performance of rugby players. Purpose: The purpose of this investigation was to compare the effects of sprint training while carrying a ball vs. sprint training without carrying a ball on the sprint performance of junior elite rugby league players. Methods: Twenty-four junior elite rugby league players were divided into a ball carry group (BC; n = 12) and a no ball carry group (NBC; n = 12). The players of the BC group were required to catch and carry the ball under one arm during each sprint whereas the NBC group performed sprints without carrying a ball. The 8-week training intervention took place during the precompetitive phase of the season and consisted of 2 sessions per week. Sprint performance was measured prior to and after the training intervention with 40-m linear sprints performed under 2 conditions: with and without ball carry. A 3-way (group × time × condition) factorial ANOVAs was performed to compare changes in sprint performance with and without the ball, before and after the training intervention for both BC and NBC training groups Results: The BC and NBC groups experienced similar improvements in 10, 20 and 40-m sprint times and acceleration, regardless of the condition under which the sprint tests were performed. Figure 1 shows the percent decrease in sprint time for the BC and NBC groups after the training intervention. Conclusions: Sprint training while carrying a rugby ball is as effective as sprint training without carrying a rugby ball for improving the sprint performance of elite junior rugby league players. Practical Applications: Speed drills while carrying the ball can be integrated into rugby practices to improve the sprint performance of elite rugby league players to the same degree as traditional speed drills without ball carry. This is particularly of interest to coaches during the precompetitive phase of the annual calendar or during congested training and playing schedules during the in-season since the sprint performance of the players can be improved using specific drills in which technical and tactical skills are involved in conditions similar to actual competition.

Friday, July 11, 2014, 9:00 AM–9:15 AM

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3. Fatty Acid Blood Levels, Vitamin D Status, and Physical Performance and Its Relationship to Resiliency and Mood in Active Duty Soldiers

N. Barringer,1 R. Kreider,2 S. Crouse,2 M. Greenwood,2 T. Elliott,2 R. Kotwal,3 S. Carroll,4 and R. Dalton2

1ESNL Texas A&M University; 2Texas A&M University; 3Trauma Care Delivery at Joint Trauma System, Defense Center of Excellence for Trauma; and 41st Brigade Combat Team, first Cavalry Division

*Award Eligible—Doctoral Student Research Award for an outstanding podium abstract presentation.

The mental health of Soldiers is a growing concern as rates of depression and suicide have increased in Soldiers with recently more deaths attributed to suicide than deaths due to combat in Afghanistan in 2012. Previous research has demonstrated the potential for eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), Vitamin D, physical activity, and physical fitness to improve depression/quality of life scores. Purpose: To determine if fatty acid blood levels, Vitamin D status and physical activity are associated with physical fitness scores, measures of mood, and measures of resiliency in active duty Soldiers. Methods: One hundred active duty males (mean ± SD age, 26 ± 5.6 years; height 69.2 ± 3.2 inches, weight 185 ± 26 pounds) volunteered for this study. The study took place over a period of 3 days. On Day 1 participants signed consent forms and filled out a questionnaire with background information, the Dispositional Resiliency Scale-15 (DRS-15), Big 5 Personality Test, International Physical Activity Questionnaire (IPAQ), and the Patient Health Questionnaire-9 (PHQ-9). On day 2 patients reported fasted and blood samples drawn for Omega-3 and Omega-6 fatty acids and Vitamin D (25(OH)D). On day 3 subjects completed a standard Army Physical Fitness Test (APFT) consisting of 2 minutes of push-ups, 2 minutes of sit-ups, and a 2 mile run for time. Blood samples were analyzed using liquid chromatography, tandem mass spectrometry (LC/MS/MS) measurement of arachidonic acid (AA), EPA, DHA, and total phospholipid fatty acids and vitamin D. Data were analyzed using IBM SPSS statistics software. Bivariate Correlation was run on variables and then hierarchical regression analysis was used to determine if combined variables presented a stronger model. Results: PHQ-9 Scores were correlated using Pearson correlation with DRS-15 scores (r = −0.533), 2-mile run time (r = −0.336), APFT (r = −0.245), and Big 5 Personality Test (r = −0.301), but only DRS-15 and APFT were significant in the hierarchical regression with an r = 0.33. DRS-15 was negatively associated with AA blood levels and total sitting time (r = −0.21 and r = −0.20, respectively). Run times were negatively correlated with Vitamin D (r = −0.21). Push-ups were positively correlated with EPA (r = 0.26) and sit-ups were positively correlated with both EPA and DHA (r = 0.26 and r = 0.21, respectively). Conclusions: The DRS-15 could be utilized as a tool to combat depression scores as higher scores in resiliency were correlated with lower scores in depression. Faster run times were also associated with lower depression scores so fitness is important for both the physical and mental health of the Soldier. We also see that total sitting time and a diet high in omega-6 fatty acids might threaten resiliency. Vitamin D, EPA, and DHA also demonstrated a statistically significant relationship with physical fitness measures which supports previous research. Further research needs to be done to determine a cause and effect relationship but it is prudent given the current findings to recommend increased physical activity and a diet with adequate vitamin D and Omega-3s as a potential strategy to support Soldier resiliency. Practical Application: Although cause and effect is not established it is prudent given the current findings to recommend increased physical activity and a diet with adequate vitamin D and Omega-3s as potential method to support Soldier resiliency.

Friday, July 11, 2014, 9:15 AM–9:30 AM

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4. Evaluating Squat Attempt Velocities of Collegiate and Open Powerlifters as a Marker of Performance and Indicator of Success During Competition

C. Dolan,1 J. Quiles,1 A. Klemp,1 K. Schau,1 B. Esgro,1 E. Jo,2 and M. Zourdos1

1Florida Atlantic University; 2California State University Pomona

*Award Eligible—Master's Student Research Award for an outstanding podium abstract presentation.

The squat is one of the competitive disciplines in the sport of powerlifting, where 3 attempts are allowed for the squat, bench press, and deadlift. Therefore, competitors must exhibit high levels of technical mastery over the skill of squatting to optimize performance at or near maximal intensities. The velocity of the squat between lifters with varying levels of experience has been investigated as a marker of neuromuscular efficiency. However, an examination of squat velocity as a marker of performance and predictor of success in powerlifters has yet to be investigated. Purpose: To compare average and peak velocities of the first squat attempt, and third squat attempt between collegiate powerlifters (CPL) and open powerlifters (OPL). An additional aim was to determine if a correlation exists between the average velocity of the first squat attempt and successful subsequent squat attempts in powerlifters. Methods: Thirty-Five competitive powerlifters attending the 10th Anniversary USAPL Florida Collegiate State Championships (n = 26, 19 males and 7 females) (weight.: 81.25 ± 25.63 kg.; body fat: 13.96 ± 6.38%) and the 10th Anniversary USAPL Southeastern USA Regional Open Championships (n = 9, 8 males and 1 female) (weight.: 87.23 ± 17.82 kg.; body fat: 12.59 ± 5.67%) agreed to allow their squat attempt velocities to be recorded via a Tendo unit, which was attached to the barbell. All subjects performed 3 squat attempts in which their goal was to successfully complete one repetition at or near maximal intensity. Average velocity was recorded for all squat attempts made by each competitor. A paired t-test was utilized to analyze the average velocity between groups, and a Spearman's correlation was used to determine whether the average velocity of the first attempt correlated to the success of subsequent attempts. Significance was set at p ≤ 0.05. Results: The first squat attempt average velocity was not significantly different (p > 0.05) between CPL (0.44 ± 0.09 m/s) and OPL (0.40 ± 0.07 m/s). Similarly, third squat attempt average velocity was not significantly different (p > 0.05) between CPL (0.35 ± 0.08 m/s) and OPL (0.28 ± 0.09 m/s). No correlation appears to exist between the average first squat attempt velocities and successful subsequent squat attempts (R = 0.08, p > 0.05). Interestingly, CPL did exhibit greater peak velocity on the first attempt compared to OPL (CPL: 0.87 ± 0.17 m/s, OPL: 0.72 ± 0.12 m/s). Conclusions: Our findings demonstrate that CPL and OPL exhibit similar average squat velocities in the first and third squat attempts during competition. However, CPL had a greater peak velocity (p ≤ 0.05) compared to OPL during first attempts, possibly showing inefficiency even though average velocities were similar between groups. Additionally, it does not appear that first squat attempt average velocity was an indicator of total successful attempts. Practical Application: Our results indicate that no correlation could be made between first attempt average velocity and subsequent successful attempts. However, it does appear that less experienced powerlifters (i.e., CPL) may be less efficient and less skillful than more experienced powerlifters (i.e., OPL), thus CPL should take caution in selecting an appropriate opening attempt to ensure successful completion. Acknowledgments: The authors would like to thank Dr. Robert Keller and USA Powerlifting for the opportunity to conduct the study.

Friday, July 11, 2014, 9:30 AM–9:45 AM

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5. Effect of Resistance Exercise Intensity on RPE, Heart Rate, VO2, Blood Lactate and Peak Power

C. Goodman, L. Vasquez, C. Capps, J. McBride, R. Battista, and U. Alan

Appalachian State University

*Award Eligible—Master's Student Research Award for an outstanding podium abstract presentation.

Purpose: The efficacy of rating of perceived exertion (RPE) has been studied extensively in regards to aerobic exercise. However, studies examining RPE and resistance exercise are more limited, especially when performing sets to volitional failure. The purpose of this study was to evaluate the effects of various intensities of 1 repetition maximum (1RM) squatting performed to volitional failure on measures of RPE, heart rate (HR), oxygen consumption (

), blood lactate (BLA) and peak power (PP). Methods: Twelve male volunteers (age: 21.4 ± 1.7 years, height: 176.8 ± 4.8 cm, body mass: 77.6 ± 10.3 kg,

: 53.8 ± 5.9 ml/kg/min, 1RM Squat: 119.8 ± 22.8 kg) completed 2 sessions separated by a minimum of 3 days. During the first session a 1RM in the back squat was obtained from each subject with all squats performed to a 70° knee angle. In the second session, subjects performed a set of squats in a randomized fashion at 50, 70, and 90% of the previously determined 1RM. During the testing session, the subject was attached to a metabolic cart in order to assess

. Breath-by-breath analysis of percent expired carbon dioxide, percent expired oxygen, and total volume of expired air was collected and analyzed. HR was measured using a heart rate monitor strapped at sternum level of the subject. A 0.7 µL blood sample before and immediately post each trial was taken in order to analyze BLA by a finger prick using a Lactate Plus analyzer. Perception of effort was evaluated throughout each testing session using Borg's 6-20 scale. Ten minutes of rest was given between each condition. HR, BLA,

and PP were accessed prior to each condition to ensure values were at resting levels. Each set was performed to volitional failure (50-F, 70-F, 90-F) and measures were assessed immediately after completion of each set. Results: HR (50%: 159.9 ± 23.0; 70%:161.0 ± 11.3; 90%: 150.6 ± 16.4 bpm) and

(50%: 29.7 ± 10.2; 70%: 27.6 ± 11.6; 90%: 16.2 ± 4.5 ml/kg/min) were significantly lower in 90-F in comparison to 70-F and 50-F (p < 0.001). BLA (50%: 11.0 ± 5.3; 70%: 10.8 ± 5.6; 90%: 8.5 ± 6.0 mmol/L) (p = 0.89) and RPE (50%: 16.3 ± 1.6; 70%: 16.2 ± 2.2; 90%: 15.7 ± 2.0) (p = 0.92) were not significantly different between any of the conditions. Peak power during the first repetition (PPf) (50%: 1440 ± 365; 70%: 1667 ± 282; 90%: 1773 ± 477 W), peak power during the last repetition (PPl) (50%: 976 ± 430; 70%: 1109 ± 324; 90%: 1460 ± 450 W), % change in peak power (%PP) (50%: 11.0 ± 5.3; 70%: 10.8 ± 5.6; 90%: 8.5 ± 6.0%) were not significantly different between any of the conditions (p = 0.62) Repetitions were significantly different between all conditions (50%: 33.5 ± 7.3; 70%: 16.3 ± 4.7; 90%: 3.3 ± 2.6#) (p < 0.001). Conclusions: HR and

appear to be intensity dependent when performing a set to volitional failure to some extent. However, this was not a linear pattern in that the HR and

values were not significantly different between 50% and 70% of 1RM. RPE was not significantly different between any of the conditions and thus there appears to be no specific relationship between RPE, intensity and the HR and

responses. Based on the data from the current investigation it appears that BLA and PP% (i.e., fatigue) could be more of a mitigating factor for perception of effort when performing a single set of squats to volitional failure independent of the intensity (% of 1RM). Practical Application: Due to the commonality of fatigue when performing a resistance exercise to volitional failure, RPE may not allow for an individual to differentiate between a set performed with either 50%, 70% or 90% of 1RM. Care should be taken if attempting to use RPE to identify training loads especially when sets are performed at or near volitional failure.

Friday, July 11, 2014, 9:45 AM–10:00 AM

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6. Power, Aerobic Capacity, and Ventilatory Threshold Changes due to a Monitored Periodized Training Program in Female Division I College Soccer Players

A. Walker, J. Pellegrino, K. Dods, and S. Arent

Rutgers University, IFNH Center for Health & Human Performance

*Award Eligible—Master's Student Research Award for an outstanding podium abstract presentation.

Despite performance and injury-prevention benefits of strength training, soccer teams often neglect it in order to emphasize aerobic training. Well-designed periodization programs should allow improved power without sacrificing aerobic capacity. Purpose: To determine the effects of a year-long periodization plan emphasizing strength training on changes in aerobic capacity, ventilatory threshold (VT), and power in a women's college soccer team. Methods: Division I female college soccer players (N = 25; Mweight = 64.7 ± 1.2 kg) participated in the modified training program from the start of Spring training through the end of the competitive season. Athletes underwent performance testing 4 times throughout the program: before (T1) and after (T2) Spring training, at the beginning of pre-season (T3), and after their last NCAA tournament game (T4). Testing consisted of vertical jump (VJ) to assess power and a maximal graded exercise test (GXT) to assess

and VT via direct gas exchange. Given the history of injuries and low power values of the team, the periodization program stressed power and strength training. The primary mode of aerobic training was through intervals and small-sided games. The program gradually transitioned from 4 days of weight lifting in the Spring season to 1 day per week in-season due to increased sport demands. Training intensity and weekly training load was monitored through use of the algorithms in the Polar Team 2 Pro System. Results: There were significant effects of Time on VJ (p = 0.015) and VT (p = 0.019). VJ was significantly increased from T1 to T2 (4.9 ± 1.8 cm, p = 0.027) and T3 (4.6 ± 1.5 cm, p = 0.023), before returning towards T1 levels by T4 (3.6 ± 1.5 cm, p = 0.115). VT remained relatively stable from T1 to T2 (0.9 ± 1.3 %

, p = 0.908), before significantly increasing by T3 (3.1 ± 1.2%

, p = 0.050). By T4, VT had returned to T1 values (0.2 ± 1.2 %

, p = 0.998). There were no significant changes in

(p = 0.777), with an average value of 48.8 ml O2/kg/min at the start of the season. The largest decreases in VJ and VT were seen for players exceeding 1100 training load points on the Polar Team2 System on average in-season. Conclusions: Periodization focused on strength training during the Spring and early Summer training (T1–T3) increased the players' power while maintaining aerobic fitness. During the summer training, players were able to sustain power improvements while also increasing VT as they began to emphasize sport-specific training in preparation for the season. The decrease in both VJ and VT during the season (T4) suggests a need to modify the in-season strength training program while also identifying indicators of overreaching. Training load data from the Polar Team 2 System supports its efficacy for monitoring training stress and provides evidence for a threshold for optimal training to support off-season gains. Practical Application: The use of periodization emphasizing strength training in female college soccer players successfully increases power and aerobic efficiency during the off-season without sacrificing aerobic capacity. This has the potential to improve on-field performance and reduce injury. Properly applied periodization throughout the year can lead to increased performance if work load is monitored and the increased need for recovery and continued strength training in-season is recognized. Acknowledgments: Thanks to the Rutgers Women's Soccer Team.

Friday, July 11, 2014, 10:00 AM–10:15 AM

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7. Effects of Vibration Massage on DOMS, Using a Car Buffer

E. Weigel and P. Appicelli

Winona State University

*Award Eligible—Master's Student Research Award for an outstanding podium abstract presentation.

Delayed Onset Muscle Soreness (DOMS) is the pain and stiffness felt in muscles several hours to days after unaccustomed eccentric and/or strenuous exercise. This damage can result in decreased muscle force production, increased serum creatine kinase activity, inflammation, and increased proteolytic activity. Several interventions have been used to minimize the symptoms of DOMS. Two of the more common are vibration massage and deep tissue massage. The use of a hand held buffer has the potential to massage and vibrate the affected tissue. Purpose: The purpose of this study was to simulate a deep tissue massage and a form of vibration therapy with using only a hand held car buffer. Methods: Fifteen male trained subjects between the ages of 20–26 years were used for this study. Ten subjects were used as a treatment group and 5 as a control. All subjects received pre-exercise measurements, including hip flexion with a goniometer, muscle tenderness of the hamstring using a digital force pressure gauge, and perceived pain (PP) on a 1 to 10 scale level of soreness. Subjects then performed a high volume hamstring workout to induce soreness. The workout included approximately 4 sets of 10–12 reps of hamstring curls, glute/ham raises, and RDLs. On day 2 all subjects were assessed with the same 3 measurements as day one. Subjects in the treatment group then received buffer treatment for one minute to the hamstring and were then re-measured with the same 3 measurements after receiving the buffer treatment (control group was measured twice but no buffer treatment was applied between measurement bouts). On day 3 subjects underwent the same protocol as day 2, which included pre-measurements, buffer treatment, and post-buffer treatment. A repeated measures ANOVA was used to determine statistically significant differences Results: Average data for the treatment [buffer] and control group is shown in the table below (mean +standard deviation). The exercise protocol was sufficient in inducing DOMS symptoms in both groups. The buffer group showed a significant difference in pre-to post-measurements on each treatment day. There were no significant pre-to post-measurement differences seen in the control group. Conclusions: A brief (1 minute) application of a hand held buffer does have at least a short term effect on DOMS. These effects include an increase in range of motion, an increase in pressure tolerance, and a decrease in reported pain. Practical Application: Strength and conditioning professionals can use a hand held buffer on their athletes/clients to reduce the effects of DOMS by using it pre- and post-workout on their affected muscle groups.

Friday, July 11, 2014, 10:15 AM–10:30 AM

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8. Influences of Training Status on Acute Isometric Force Percent Decline Following Concentric vs. Eccentric Exercise

X. Ye, T. Beck, N. Wages, J. Carr, and C. Miller

University of Oklahoma

*Award Eligible—Doctoral Student Research Award for an outstanding podium abstract presentation.

Eccentric exercise (ECC) has been used as a common exercise intervention in laboratory testing and exercise training program for decades. Unlike concentric exercise (CON), ECC is believed to induce not only muscle fatigue, but also muscle damage. Therefore, as an important muscle damage marker, acute strength loss following ECC is generally more severe. However, this could be affected by many factors. Purpose: This study compared acute isometric strength percent decline in resistance trained (RT) and untrained (UT) individuals following the ECC and CON exercises. Methods: Twenty-four college-aged men participated in this study and finished 2 randomized visits. Thirteen of them were defined as RT (mean ± SD; age = 24 ± 4 years; height = 180.2 ± 7.7 cm; weight = 92.2 ± 16.9 kg); and the remaining 11 were defined as UT (mean ± SD; age = 23 ± 4 years; height = 179.3 ± 5.2 cm; weight = 81.5 ± 9.0 kg). The CON and ECC exercises were randomly assigned to each subject during visits 1 and 2. At the beginning of each visit, all subjects performed 2 isometric maximal voluntary contractions (MVCs) in a strength testing apparatus for their elbow flexors. The higher MVC was then recorded as pre-testing isometric strength (PRE). Immediately after the strength testing, subjects performed 6 sets of 10 elbow flexion contractions (CON or ECC) on an isokinetic dynamometer at a velocity of 60° per second, and one minute of rest was provided after each exercise set. Once they finished the exercise intervention, post-isometric strength (POST) was then tested. Isometric strength percent decline for each individual was calculated as (PRE - POST)/PRE × 100%. A 2-way (training status [RT vs. UT] × condition [CON vs. ECC]) mixed factorial analysis of variance (ANOVA) was performed to compare the percent declines in isometric strength between these 2 groups during different exercise interventions. When appropriate, follow-up analyses included independent samples t-tests and paired samples t-tests. Results: The results showed that there was a significant 2-way interaction (p = 0.038). In addition, independent samples t-tests showed that there was no significant difference in isometric strength percent declines between RT and UT following the CON; however, UT showed higher percent decline in isometric strength following the ECC (mean ± SD: RT vs. UT = 24.14% ± 9.89% vs. 33.79% ± 9.89%, p = 0.013). Furthermore, paired samples t-tests showed that isometric strength percent declines were similar for RT following both the CON and ECC, but not for UT (mean ± SD: CON vs. ECC = 26.21% ± 8.11% vs. 33.79% ± 9.89%, p = 0.015). Conclusions: High intensity CON induced similar strength loss for RT and UT individuals. However, UT suffered more strength loss following the ECC exercise. In addition, strength loss in RT was not specific to the training condition (CON or ECC). Practical Application: Testers and practitioners should realize that testing strength loss following eccentric exercise is probably not a valid marker of muscle damage for resistance trained individuals, since eccentric exercise-induced strength loss is similar to that caused by concentric exercise in this population.

Friday, July 11, 2014, 10:45 AM–11:00 AM

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10. Effect of Different Forms of Suspension Exercise on Energy Expenditure, Endocrine Responses and Force Production Post Push-Up Exercise

D. Bellar,1 C. Etheredge,1 and L. Judge2

1University of Louisiana at Lafayette; and 2Ball State University/School of PE, Sport, and Exercise Science, Muncie, IN

Purpose: This investigation sought to examine changes in force production, endocrine response and energy expenditure following 2 forms of suspension push-ups and an isotonic bench press. Methods: Participants included 15 college aged males (mean ± SD; Age 24.7 ± 3.6 years; height 178.6 ± 4.3 cm; weight 81.1 ± 5.8 kg) with greater than 1 year experience with resistance training. The participants reported to the lab on 10 occasions. The first visit included anthropometric measurements, average support weight during a suspension push up, familiarization with the isometric upper body strength assessment, and practice with all 3 exercise types in cadence with a metronome set to 60 bpm. The 3 forms of exercise included a barbell bench press using a weight corresponding to the average support weight during a suspension push-up (BP), a suspension push up with straps for the hands only (DUAL) and a suspension push up with straps for the feet and hands (QUAD). All exercise repetitions were performed in cadence to a metronome set at 60 bpm. In a random order of exercise type, participants engaged in 3 additional trials consisting of 6 sets of 10 repetitions where saliva samples were collected pre and post exercise, and upper body isometric strength measures were collected immediately post, 1 hour post, 24 and 48 hours post. Expired gases were monitored continuously during the exercise. After all trials were completed, commercial ELISA kits (n = 12) were used to analyze saliva samples for testosterone (TEST) and cortisol (CORT) concentrations. Results: Repeated measures Anovas were used to examine changes in isometric peak strength, TEST, CORT and oxygen consumption by exercise type (BP, DUAL, QUAD). Analysis of isometric peak strength revealed a main effect for time (F = 10.22, p ≤ 0.001) but no significant main or interaction effects for exercise type (p > 0.55). Analysis of TEST did not reveal any significant main or interaction effects though mean levels were higher after exercise (pre: 139.9 pg/ml; post 160.0 pg/ml). Similarly, analysis of CORT did not reveal any significant main or interaction effects. Analysis of oxygen consumption data revealed a significant main effect for exercise type (F = 8.20, p ≤ 0.001). The QUAD condition resulted in the greatest oxygen consumption (13.03 ± 2.57 L/min) compared to the DUAL (12.37 ± 1.17 L/min) and the BP (10.68 ± 2.41 L/min). Conclusions: Based upon these data, suspension exercise when compared against traditional resistance exercise with comparable resistance, results in similar reductions in muscle force production post exercise, and similar endocrine responses. However, oxygen consumption is increased over traditional resistance exercise and is greatest with both the feet and hands suspended. Practical Application: Strength and conditioning professionals should be aware that suspension exercise appears to have similar effects when compared to traditional resistance exercise when matched for resistance and tempo. However, energy expenditure is higher in suspension exercise in these instances. Acknowledgments: This study was funded by a grant from TruFit, LLC.

Friday, July 11, 2014, 11:00 AM–11:15 AM

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11. Evidence of Exercise-Induced Hypogonadism in Men Competing at the 2011 Ironman World Championships

D. Hooper, W. Kraemer, B. Kupchak, R. Stearns, B. Volk, W. DuPont, A. Sterczala, D. Looney, T. Szivak, S. Flanagan, M. White, B. Comstock, C. Maresh, and D. Casa

University of Connecticut

It has been previously identified that chronic and intense aerobic endurance training can result in a substantially reduced serum total testosterone concentration, eventually leading to an exercise-induced hypogonadism. Although this problem has been identified in a resting state, the circulating hormonal concentrations of testosterone surrounding an acute aerobic demand have not been analyzed. Purpose: The purpose of the study was to examine the circulating testosterone concentrations before, immediately after and for 2 days following participation in the 2011 World Ironman Championships in Kona, Hawaii. Methods: 22 men (age 40.6 ± 11.5 years; height 178.8 ± 6.1 cm; body fat 10.1 ± 3.1%) volunteered to participate in the investigation. Blood samples were taken at baseline (BL) 2–4 days before the event. Subjects then reported to the medical tent immediately following the event (IP), and again for further analyses 12-18- (D1) and 36–42-hours (D2) post-race. Results: At BL 15 of the 22 men met the criteria for hypogonadism (Total testosterone (TT): <14 nmol·L−1). Mean TT for all subjects was slightly above the criteria for hypogonadism (14.04 ± 8.96 nmol·L−1) at BL. TT was not significantly different (p ≤ 0.05) from BL at IP (14.61 ± 10.1 nmol·L−1). At D1 TT was significantly (p ≤ 0.05) lower than BL (9.03 ± 7.43 nmol·L−1) and 17 of the 22 men now met the criteria for hypogonadism. By D2, TT had significantly (p ≤ 0.05) increased (11.04 ± 8.22 nmol·L−1). There was no significant correlation between TT and age at BL (r = 0.201), nor with TT and time to complete the event (r = 0.197). Conclusions: The intense training required to participate in the Ironman World Championships appears to be resulting in substantially reduced TT concentrations, leading many men to reach the criteria to be considered clinically hypogonadal. Practical Application: Men participating in training for Ironman competitions should carefully monitor TT and possibly tailor their training accordingly in order to avoid negative symptoms associated with hypogonadism.

Friday, July 11, 2014, 11:15 AM–11:30 AM

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12. Effects of Caloric Load on Resistance Training Adaptations in Body Composition

S. McCleary,1 R. Lowery,2 J. Rauch,1 J. Silva,1 J. Ormes,2 K. Shields,2 S. Weiner,2 J. Georges,2 J. Joy,2 and J. Wilson2

1University of Tampa; and 2University of Tampa Human Performance Lab

*Award Eligible—Master's Student Research Award for an outstanding podium abstract presentation.

Athletes across a number of sports and athletic disciplines find themselves in an endless search for new and effective methods of gaining mass. One method concerns the modulation of calorie intake with athletes attempting to gain mass by consuming an extremely high caloric surplus. However, to date the dose response of overfeeding remains to be investigated. Purpose: To investigate the effects of 5 weeks of moderate and high overfeeding on body composition. Methods: Fourteen recreationally trained athletes were recruited for this study. Individuals were assigned to increase their calories by a moderate (825/calories per day, Pursuit Rx) or a high (2,280 calories per day, Honeyville Whey Concentrate and Maltodeuxtrin Blend) amount of calories in addition to their habitual daily food intake. Subjects performed full body resistance training twice a week for a 5-week period. Total mass, lean body mass, and fat mass were measured at weeks 0 and 5 of the study. Results: There were group by time interactions for total body mass, and fat mass. Total mass in the high group (4.3 ± 1.3 kg) was approximately double that of the moderate group (1.97 ± 0.2 kg). Fat mass increased to a greater extent in the high group ((1.04 ± 1.1 kg) than in the moderate group (−1.54 ± 1.2 kg), while lean body mass increased equally in both the moderate (3.9 ± 2.0 kg) and the high group (3.1 ± 1.7 kg). Conclusions: These results suggest that moderate overfeeding combined with resistance training results in more favorable changes in body composition than extreme overfeeding. Practical Application: Athletes looking to gain mass should do so. Based on our data, athletes should consume moderate more calories if looking to add mass.

Friday Poster Presentations

July 11, 2014, 11:30 AM–1:00 PM

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1. Time Course Response of Postprandial Oxidative Stress Is Not Mediated by Exercise Training in Prediabetics

P. Tucker,1 V. Dalbo,1 M. Roberts,2 A. Scanlan,1 and R. Bloomer3

1Central QLD University; 2Auburn University; and 3University of Memphis

*Award Eligible—Doctoral Student Research Award for an outstanding poster abstract presentation.

Purpose: Nearly 26 million people (8% of the U.S. population) have diabetes, while another 79 million people (25%) have pre-diabetes. One of the primary contributors to the damage associated with metabolic disorders is postprandial oxidative stress (PPOX). PPOX is characterized by an increased susceptibility to oxidative damage following the consumption of a meal rich in lipids and/or carbohydrates. Individuals who spend the majority of their day in a postprandial state are at increased risk of diet-induced oxidative stress. Thus, individuals with metabolic disorders (e.g., pre-diabetics) experience increased damage due to PPOX, compared to healthy counterparts. Chronic aerobic exercise reduces systemic oxidative stress via enhanced antioxidant defenses, reduced blood glucose, and reduced blood triglycerides. What is less clear is whether chronic aerobic exercise can influence the PPOX response to lipid/carbohydrate feedings, and whether the time-course and magnitude of PPOX is different between exercise-trained and untrained individuals. The purpose of this study was to determine the effects of chronic aerobic exercise on PPOX in a group of pre-diabetics. Methods: Eighteen sedentary, prediabetic (fasting plasma glucose of 100–125 mg/dl) men and women (age: 18–55 years) were recruited. Participants were randomly assigned to one of 2 groups: aerobic exercise training (AET) or a sedentary control group (SED). The AET group engaged in progressively increasing intensity aerobic exercise training using a cycle ergometer (to 80–85% of HRR by week 6) for 45–60 minutes, 3 days per week, for 8 weeks. The SED group maintained normal activity levels for 8 weeks. Participants consumed a standardized high fat, high carbohydrate test meal (1.2 g of fat and 1.2 g of carbohydrate per kg of body mass) following the experimental period. Blood samples were collected pre-meal, and at 1, 2, 4, and 6 hours, postprandial. Blood samples were assayed for malondialdehyde (MDA), xanthine oxidase activity (XO), hydrogen peroxide (H2O2), glucose (GLU), and triglycerides (TAG). Pearson correlations were used to assess the relationship between the groups' postprandial time-course response (PTCR) of MDA, XO, H2O2, GLU, and TAG. Statistical significance was set at p ≤ 0.05. Results: The PTCR of each marker was significantly correlated between AET and SED groups. Results were as follows: MDA (r = 0.91), XO (r = 0.91), H2O2 (r = 0.99), GLU (r = 0.91), and TAG (r = 0.83). Conclusions: Results from this study indicate that 8 weeks of AET does not alter the PTCR of oxidative stress markers MDA, XO, and H2O2 or related macronutrient markers GLU and TAG. Practical Application: While previous studies have reported a reduction in basal levels of oxidative stress following AET, the PTCR of oxidative stress is strongly correlated between exercise-trained and sedentary prediabetics. Given the increased risk of PPOX-mediated damage in prediabetics, defining the activity of oxidative stress markers and related macronutrient markers is an important step in characterizing the effects of AET on PPOX. Due to the favorable effects of AET, including enhanced antioxidant defenses, improved glucose tolerance, and improved triglyceride clearance, AET should continue to be encouraged, despite the strongly correlated PTCR of MDA, XO, H2O2, GLU, and TAG between AET and SED groups.

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2. The Acute Hormonal Response to 164 km Road Cycling in a Hot Environment

R. Budnar,1 J. Vingren,1 A. Duplanty,1 A. Fernandez,1 A. McKenzie,2 H. Luk,1 D. Levitt,1 T. Layman,1 D. Hill,1 B. McFarlin,1 K. Williamson,3 and L. Armstrong2

1University of North TX; 2University of Connecticut; and 3Midwestern State University

*Award Eligible—Doctoral Student Research Award for an outstanding poster abstract presentation.

Purpose: The purpose of this study was to investigate the acute hormonal response to a 164 km road cycling event in a hot environment. Methods: Thirty-four experienced male cyclists (49.1 ± 8.3 years, 86.8 ± 12.5 kg, 178.1 ± 5.1 cm, 18.5 ± 5.1% body fat) were recruited at the August 2013 Hotter’N Hell Hundred (164 km) road cycling event held in Wichita Falls, TX. Blood samples were collected within 2 hours of the start (PRE: ∼0500–0700h) and immediately following completion (POST) of the 164 km ride. During the event, wet bulb globe temperature was 31.4 ± 3.8 [Combining Ring Above]C with a maximum of 36.1 [Combining Ring Above]C and cloud cover was minimal. Samples were analyzed for total testosterone, growth hormone, and cortisol. Participants were grouped based on finishing group (fastest [FAST] and slowest [SLOW] 25th percentile) to examine the effect of event duration on the hormonal response. Results: At POST, testosterone concentration was significantly (p ≤ 0.05) lower (PRE: 20.8 ± 8.6; POST: 18.2 ± 6.7 nmol·L−1) while growth hormone (PRE: 0.3 ± 0.1; POST: 2.3 ± 0.3 µg·L−1) and cortisol concentrations (PRE: 661 ± 165; POST: 1073 ± 260 nmol·L−1) were significantly higher than at PRE. Testosterone was not different based on finishing group (FAST vs. SLOW), though a statistical trend (p = 0.08) was found for an interaction effect between finishing group and time point (PRE vs. POST). A significant interaction was found for finishing group and time point for growth hormone and cortisol. At PRE, there was no difference between groups for growth hormone (FAST: 0.2 ± 0.1; SLOW 0.3 ± 0.3 µg·L−1) or cortisol (FAST: 626 ± 169; SLOW: 608 ± 135 nmol·L−1). At POST, growth hormone and cortisol were significantly higher for the FAST group than for the SLOW group (Growth Hormone: 3.3 ± 1.9 and 1.1 ± 0.9 µg·L−1; Cortisol: 1232 ± 195 and 856 ± 229 nmol·L−1; FAST and SLOW, respectively). Conclusions: Participation in an ultra-endurance road cycling event in hot environment induced a significant acute change in concentrations of circulating hormones. This effect was more pronounced in the group that completed the event faster, even though the duration of heat exposure in the faster group was considerably less. Therefore, the speed at which a cyclist completes an endurance event appears to have a greater impact on the acute hormonal environment than does heat exposure. Practical Application: Cyclists engaging in ultra-endurance events in hot weather conditions should be cognizant of the acute physiological impact of such extreme events. Even when in a hot environment, finishing a long distance cycling event (e.g., 164 km) faster appears to have a greater impact on the acute hormonal response than finishing the event more slowly, especially for cortisol and growth hormone. Though the long-term effects of an acutely altered hormonal milieu are not well understood, it is possible that acute changes in hormonal homeostasis could influence muscle metabolism and subsequent training adaptations.

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3. The Oral Bioavailability of Adenosine Tri-Phosphate's Following an Intense Sprinting Protocol

J. Rauch,1 R. Lowery,2 J. Silva,1 M. Sharp,2 S. McCleary,1 J. Joy,2 J. Ormes,2 K. Shields,2 J. Georges,2 S. Weiner,2 and J. Wilson2

1University of Tampa; and 2University of Tampa Human Performance Lab

*Award Eligible—Undergraduate Student Research Award for an outstanding poster abstract presentation.

Adenosine-5'-triphosphate’s (ATP) role as the primary intracellular energy source for body tissues is well established. One extracellular-mediated function of ATP includes the modification of muscle excitability (i.e., increasing skeletal muscle calcium permeability and blocking chloride efflux) and vasodilation. However, to date there is a paucity of research investigating the bioavailability of ATP and its metabolites. Moreover, no study to date has investigated how exercise acutely impacts blood levels of ATP following supplementation. Purpose: To conduct a pilot study to investigate the oral bioavailability of ATP following 10 maximal, 6 seconds sprints performed after 15 days of supplementation. Methods: Ten NCAA National Championship baseball athletes were recruited for this study. A double-blind, placebo controlled trial consisting of individuals either consuming 400 mg/d of Peak ATP (TSI, Inc.) or 400 mg/d placebo was conducted. Subjects also consumed 400 mg on day 15, 30 minutes before an exercise bout. Results: Whole blood ATP decreased in the placebo (−143.1 ± 187.5) and increased in the supplemented group from pre to post sprint (116.2 ± 88.2 µM, Group × Time, p = 0.02). In the similar manner ADP declined in the placebo (−37.6 ± 50.7) but was maintained in the ATP group (0.49 ± 14.5 µM, Group × Time p = 0.03) from pre to post sprint. There was no significant change in blood AMP levels. Conclusions: The pilot study data suggest that Peak ATP supplementation was able to sustain ATP and ADP concentrations following an intense exercise bout, indicating that the supplement may indeed bioavailable and a larger study is merited. Practical Application: Athletes looking to maintain power output during exhausting, intermittent events such as occurs during hockey, soccer, or football games may benefit from supplementing with ATP daily.

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4. Effect of a Glute-Targeted Warm-Up on Hip and Knee Moments During a Countermovement Jump

L. Barker,1 S. Lynn,1 J. Coburn,1 and L. Brown2

1CSU Fullerton Center for Sport Performance; and 2California State University, Fullerton

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

The gluteal complex is a primary mover of the hip and stabilizer of the pelvis during lower body movements.

Recently, biomechanic analysis and discussions have led to concepts of “hip-dominant” vs. “knee-dominant” movers. Hip-dominant movers have greater stress on the hip than knee, while knee-dominant movers have greater stress on the knee than hip. Purpose: The purpose of this study was to examine the effect of a glute-targeted warm-up on the sagittal plane moments at the knee and hip. Methods: Twenty-two recreationally trained males (Age: 23.14 ± 2.1 years; Mass: 85.03 ± 11.60 kg) were recruited for the study. Participants performed countermovement jumps (CMJ) pre and post a glute-targeted warm-up using resistance bands (GW) and a dynamic warm-up (DW) consisting of the same movements as the GW without resistance bands on separate days. Kinetics and kinematics of the right leg were analyzed for sagittal plane moments at the hip and knee during the CMJ takeoff and landing. Results: Results indicated no significant main effects (p > 0.05) for hip takeoff moment, hip landing moment, and knee landing moment. There was a significant increase (p ≤ 0.05) in knee takeoff moment from pre to post warm-up (DW: 1.8230 ± 0.35559 to 1.8566 0.36244; GW: 1.8195 ± 0.35744 to 1.8746 ± 0.34780) in absence of a main effect for warm-up. Practical Application: These results suggest that a glute-targeted warm-up using resistance bands has no acute effect on the sagittal moments at the hip and knee compared to a movement-matched warm up without resistance bands. The stimuli may not be sufficient to acutely shift athletes towards a hip dominant movement strategy, which has been suggested to transfer stress from the knee to the hip to reduce knee injury risk.

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5. Myotest Measures of Force, Power, and Velocity Are Correlated With the Tendo Fitrodyne and Force Plate in the Conventional Deadlift

P. Carr,1 M. Jones,1 J. Martin,1 and J. Oliver2

1George Mason University; and 2Texas Christian University

*Award Eligible—Undergraduate Student Research Award for an outstanding poster abstract presentation.

Purpose: Measures of force, velocity, and power during the conventional deadlift (DL) have been understudied. The Myotest (M), a cost effective field-based tool, has been used to measure force and power in the bench press and back squat. However, at high loads the results are equivocal. The Tendo Fitrodyne (T) has been shown to provide reliable measures of muscle power, while laboratory-based force plate (FP) systems are a reliable measure of force. Therefore, the current study sought: (a) To determine the correlation between M and a FP on force measures, and (b) To determine the correlation between M and T on measures of power and velocity. Methods: Eight females (mean ± SD: 28.9 ± 4.9 years, 163.1 ± 5.3 cm, 63.6 ± 6.1 kg) and 5 males (27 ± 10.8 years, 175.2 ± 5.1 cm, 83.1 ± 8.6 kg) with >1 year of DL experience participated in 4 testing sessions over 4 weeks. Session 1 consisted of body composition assessment ([BodPod] females: 24.8 ± 9.3% body fat [BF], males: 13.2 ± 6.4%BF) and a maximal (1RM) DL test (females: 99.2 ± 19.5 kg, males: 199.1 ± 11 kg). During sessions 2–4, subjects completed a standard supervised warm-up followed by 3 DL repetitions separated by 2-minute rest at each of 3 randomly assigned workloads (30, 60, 90% of 1RM). Sessions 2-4 were separated by 7 days. Average force (AF) and peak force (PF) were measured by the M (Myotest SA, Switzerland) (MAF, MPF) and FP (AMTI, Inc.; USA) (FPAF, FPPF). Average velocity (AV), peak velocity (PV), average power (AP), and peak power (PP) were measured by the M (MAV, MPV, MAP, MPP) and T (Tendo Sports Machines, Slovak Republic) (TAV, TPV, TAP, TPP). Data were collected concurrently for each DL trial. Bivariate (Pearson) correlations were computed. R-values between 0.71 and 0.90 were considered strong correlations. Significance (p ≤ 0.05) is reported. Results: There were strong correlations between FPAF and MAF at 30% (r = 0.932; p = 0.001), 60% (r = 0.925; p = 0.001), and 90% (r = 0.875; p = 0.001). Measures of FPPF and MPF at 30% (r = 0.979; p = 0.001), 60% (r = 0.980; p = 0.001), and 90% (r = 0.979; p = 0.001) were positively correlated. Measures of TAP and MAP at 30% (r = 0.830; p = 0.001), and 60% (r = 0.860; p = 0.001) as well as TPP and MPP at 30% (r = 0.904; p = 0.001) and 60% (r = 0.947; p = 0.001) were significant. Positive correlations were observed between TPV and MPV at 30% (r = 0.716; p = 0.006) and 60% (r = 0.723; p = 0.005). There was no significant relationship observed between M and T in AV across the 3 workloads or PV at 90%1RM (p > 0.05). Conclusions: The Myotest may be best utilized for measures of peak and average force across a variety of loads as well as peak and average power at loads Practical Application: Strength and conditioning practitioners may find the Myotest to be a convenient and cost-effective alternative to laboratory-based instrumentation when monitoring force, peak velocity, and power during DL training. If measures of average velocity are desired, it is recommended to employ other devices.

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6. Effects of Prolonged Vibration on Isometric Maximal Strength and Electromyographic Amplitude and Frequency

M. Trevino, P. Dietz, J. Springer, C. Hambleton, D. Wilson, L. Marquess, and T. Herda

University of Kansas

*Award Eligible—Doctoral Student Research Award for an outstanding poster abstract presentation.

Purpose: This study examined the effects of vibration (VIB) on muscle strength and electromyographic (EMG) amplitude (RMS) and mean power frequency (MPF) of the vastus lateralis (VL) and rectus femoris (RF). Methods: Nine individuals (5 females and 4 males; mean ± SD; age = 21.2 ± 2.4 years; height = 175.6 ± 14.3 cm; weight = 74.1 ± 19.3 kg) volunteered for this study. Before testing, a Vibrasens VB 200 massager (Techno Concepts, Pitaugier, Mane, France) was placed on the right patellar tendon and secured with a strap around the leg. Isometric force of the right leg extensors was measured with a load cell (LC402, Omegadyne, Inc., Sunbury, OH) fitted to a Biodex System 3 isokinetic dynamometer (Biodex Medical Systems, Inc., Shirley, NY, USA). Isometric muscle actions were performed at 90° of leg flexion. Participants performed 3 maximal voluntary contractions (MVC) with strong verbal encouragement for motivation followed by 10 minutes of VIB. The massager was set to 55 Hz and VIB continued during 2 additional MVCs. Surface EMG signals were recorded from the VL and the RF using a 5 pin surface array sensor (Delsys, Boston, MA). The surface EMG sensors were placed over the belly of the VL and the RF and fixed with adhesive tape with the reference electrode placed over the left patella. The sampling frequency was 2,000 Hz for all signals (NI cDAQ-9174 National Instruments, Austin, TX). The force signals were low-pass filtered (second-order Butterworth) at 20 Hz while the EMG signals were bandpass filtered (fourth-order Butterworth) at 10–500 Hz. The amplitude for the EMG signals were calculated with root mean square (RMS) and mean power frequencies (MPF) were used to express EMG center frequency. Peak force (PF) was determined as the highest 0.25 seconds epoch for each contraction and that same epoch was used to calculate EMG RMS and MPF of the VL and RF. The highest pre-MVC and VIB-MVC were used for further data analyses. Statistical analysis included 2 separate 2-way repeated measures ANOVAs (condition [Pre vs. VIB] x muscle [VL vs. RF) to examine EMG RMS (μV) and MPF (Hz) data and when appropriate, follow-up analyses were performed using paired samples t-tests with Bonferroni corrections. A paired samples t-test (Pre vs. VIB) was used to examine PF (N) data. An alpha level was set at 0.05 to determine statistical significance. Results: There was a significant decrease in PF during the VIB treatment (p = 0.043; Pre = 518.05 ± 162.70 N, VIB = 494.61 ± 176.31 N). For EMG RMS, there was a significant 2-way interaction (time x muscle, p = 0.028). EMG RMS decreased during the VIB treatment for the VL (p = 0.017, Pre = 55.20 ± 31.83, VIB = 48.15 ± 32.65 μV) and the RF (p = 0.004, Pre = 69.32 ± 39.95, VIB = 52.95 ± 31.19 μV). There was no significant interaction for EMG MPF (time x muscle, p = 0.452) or main effect for muscle (p = 0.107), however, there was a main effect for time (p = 0.021). EMG MPF increased during VIB (90.29 ± 19.18 Hz) in comparison to pre (84.61 ± 17.29 Hz) when collapsed across muscles. Conclusions: Ten minutes of continuous VIB had deleterious effects on PF. The decrease in EMG RMS for the VL and RF suggested that VIB reduced overall muscle activation. In contrast, the increase that was seen in EMG MPF for the VL and RF suggested that VIB increased conduction velocity, which is often reported during fatiguing isometric contractions. Practical Application: Prolonged (>10 minutes) whole body vibration may not be appropriate for enhancing performance.

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7. Impulse-Momentum: Functional Strength in the Context of Plyometric Training

T. Louder and E. Bressel

Utah State University

Introduction: Human strength is expressed at 4 levels physiologically: material strength of tissues, functional strength of the innervated musculotendinous unit, coordinated joint torques, and whole-body functional strength. Exercise programs aimed at improving strength should adhere to training specificity so that gains are achieved in an efficacious manner. Plyometric training can be used as a method for training the individual components of strength yet there is limited knowledge regarding which techniques might be most efficacious. This purpose of this study was to use the impulse-momentum relationship as a tool for comparing various techniques thought to improve specificity of training for functional strength. Methods: Thirteen young adults performed jumping movements under 4 conditions: drop jump (emphasis on time, DJT), drop jump (emphasis on height, DJH), countermovement (CM), and squat jump (SJ). Differences in max force (BW), max power (kW), and propulsive impulse (BW*s) across conditions were assessed with an ANOVA. Results Differences in max force (DJH: 4.3, DJT: 5.6, CM: 2.5, SJ: 2.2) were observed for all comparisons (p ≤ 0.05) with the exception of drop jumps. Differences in contact time (DJH: 0.34, DJT: 0.20, CM: 0.40, SJ: 0.51) were observed for all comparisons (p ≤ 0.05) with the exception of SJ and DJH. Impulse (DJH: 0.55, DJT: 0.52, CM: 0.39, SJ: 0.39) was greater for the drop jumps compared to both SJ and CM (p ≤ 0.05). Impulse was not different between drop jumps and between SJ and CM. Max power (DJH: 13.7, DJT: 16.5, CM: 11.5, SJ: 12.1) was greater for the drop jumps compared to the CM (p ≤ 0.05). Conclusion: The results suggest that DJT is the best plyometric exercise targeting passive force development while the others likely target high-velocity concentric force development. These results support the impulse-momentum relationship as a quantitative descriptor of functional strength and a tool to improve training specificity.

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8. Sustainability, Physiological, and Perceptual Responses at the Critical Heart Rate During Treadmill Running

H. Bergstrom,1 T. Housh,2 K. Cochrane,2 N. Jenkins,2 S. Buckner,2 J. Goldsmith,2 R. Schmidt,2 G. Johnson,2 and J. Cramer2

1University of Nebraska; and 2University of Nebraska–Lincoln

*Award Eligible—Doctoral Student Research Award for an outstanding poster abstract presentation.

The mathematical model used to estimate critical power (CP) has been applied to heart rate (HR) measurements during cycle ergometry to derive a fatigue threshold called the critical heart rate (CHR). Theoretically, the CHR represents the maximal HR that can be maintained for an extended period of time without fatigue. Purpose: This study examined the times to exhaustion (Tlim) as well as metabolic (

), neuromuscular (electromyographic amplitude; EMG AMP and EMG mean power frequency; MPF), and perceptual (ratings of perceived exertion; RPE) responses to continuous treadmill running at the CHR. Methods: Eleven moderately trained runners (mean ± SD age: 23 ± 3 years) performed an incremental treadmill test to exhaustion for the determination of the HR (HRpeak) and

(

) peak as well as the velocity associated with

(v

). On separate days, 4 constant velocity runs (79–102% v

) to exhaustion were performed. The total number of heartbeats was plotted against the time to exhaustion (Tlim) for each of the 4, constant velocity runs. The

, RPE, EMG AMP, and EMG MPF responses as well as changes in velocity were recorded during continuous runs at the CHR that were performed to exhaustion or terminated at 60 minutes. The relationships for

, HR, RPE, EMG AMP, EMG MPF, and velocity vs. time were examined using polynomial regression models (linear and quadratic) at an alpha level of p ≤ 0.05. Results: During the CHR (mean ± SD = 175 ± 8 b·min−1; 91 ± 3% HRpeak) run, the selected HR was reached within 3.25–6.57 minutes (4.34 ± 1.06 minutes) and 7 of the 11 subjects maintained exercise for 60 minutes (Tlim = 48.37 ± 11.04 minutes). The polynomial regression analyses for the mean responses during the continuous runs at CHR indicated there was no change in HR (r2 = 0.162), but quadratic decreases in velocity (R2 = 0.922) and

(R2 = 0.979), linear increases in EMG AMP (r2 = 0.862) and RPE (r2 = 0.988), but no change in EMG MPF (r2 = 0.180). Conclusions: This study indicated that on average, CHR represented a sustainable (minimum of 30–60 minutes) running intensity. During fatiguing constant HR running,

responses tracked velocity, but were dissociated from HR and EMG MPF, which remained stable, as well as EMG AMP and RPE, which increased. The decrease in

throughout the runs at a constant HR suggested that fatigue was not related to O2 availability. The increase in EMG AMP likely reflected the fatigue-induced recruitment of additional motor units and/or increases in firing rate. It is possible that the non-significant change in the frequency domain was the result of a balance between factors that tend to increase EMG MPF (i.e., increases in muscle temperature and/or recruitment of additional fast-twitch muscle fibers) and those than tend to decrease EMG MPF (i.e., the fatigue induced reduction in activation conduction velocity due to the accumulation of metabolites and ions). Practical Application: The results of the present study indicated that EMG AMP and RPE responses, but not

, HR, or EMG MPF could be used as indicators of fatigue during constant HR runs. In addition, the current findings suggested that a threshold, based on the responses of a physiological parameter, such as HR, could be used to determine the highest sustainable exercise intensity, and would provide a useful intensity for fitness assessment and training purposes. Acknowledgments: This study was funded by the 2013 National Strength and Conditioning Association Doctoral Student Research Grant.

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9. Comparison of Perceptual and Physiological Fatigue Thresholds During Cycle Ergometry

K. Cochrane,1 T. Housh,1 H. Bergstrom,2 N. Jenkins,1 S. Buckner,1 J. Cramer,1 G. Johnson,1 and R. Schmidt1

1University of Nebraska–Lincoln; and 2University of Nebraska

*Award Eligible—Doctoral Student Research Award for an outstanding poster abstract presentation.

Purpose: The purposes of this study were to: (a) compare power outputs and relative intensities that corresponded to the gas exchange threshold (GET), ventilatory threshold (VT), respiratory compensation point (RCP), physical working capacity (PWC) at oxygen consumption (PWC_(

)), heart rate (PWCHRT), and rating of perceived exertion (PWCOMNI) thresholds; (b) examine the relationships among the fatigue thresholds and the exercise intensity domains; and (c) hypothesize regarding the physiological mechanisms that underlie the fatigue thresholds. Methods: Thirteen male (n = 6) and female (n = 7) subjects (mean ± SD age: 21.8 ± 2.6 years; body mass: 70.9 ± 12.6 kg; height: 171.7 ± 11.9 cm) performed an incremental cycling test to exhaustion for the determination of

, GET, VT, and RCP. In addition, on separate days, each subject completed 4, 8-minute submaximal rides (65–80% of

) for the determination of the Physical Working Capacity at the OMNI rating of perceived exertion threshold (PWCOMNI), PWC at the Heart Rate Threshold (PWCHRT), and PWC at the Oxygen Consumption Threshold (PWC). The rates of rise in

, HR, and RPE as a function of time (linear slope coefficients) were calculated for each of the 4, 8-minute submaximal work bouts for each subject. The power outputs were then plotted as a function of the slope coefficients for the

vs. time, and HR vs., and RPE vs. time, relationships. The PWC_(

), PWCHRT, and PWCOMNI were defined as the y-intercepts of the power output vs. slope coefficient for the

vs. time, HR vs. time, and RPE vs. time plots. Statistical analysis included one-way repeated measures ANOVA with follow-up paired samples t-tests with Bonferroni corrections to compare the mean power outputs associated with the various fatigue thresholds. Results: The RCP (184 ± 47 W) was significantly (p ≤ 0.0033) greater than the GET (142 ± 38 W), VT (143 ± 40 W), PWC_(

)(106 ± 34 W), PWCHRT (108 ± 34 W), and PWCOMNI (112 ± 34 W). The GET and VT were significantly greater than the PWC_(

), PWCHRT, and PWCOMNI, but there were no differences among the PWC_(

), PWCHRT, and PWCOMNI. Conclusions: The similarity among the PWC_(

), PWCHRT, and PWCOMNI fatigue thresholds suggested that they shared a common physiological mechanism that was different from those associated with the GET, VT, and RCP. In addition, the

, HR, and RPE thresholds fell within the moderate intensity domain, while the GET, VT, and RCP occurred at significantly greater exercise intensities. These findings suggested that metabolic acidosis and hyperkalemia may underlie the GET, VT, and RCP, while increases in core temperature and/or sympathetic activation may mediate the PWC_(

), PWCHRT, and PWCOMNI thresholds. Practical Application: These thresholds can be used as sustainable exercise intensities when prescribing cycling exercise routines. Furthermore, the PWCHRT and PWCOMNI thresholds have field applications as exercise intensity can be monitored with a heart rate monitor or 0–10 scale RPE chart.

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10. Body Position's Affect on the Relationship Between Heart Rate Variability and Heart Rate Recovery in Collegiate-Female Athletes

M. Leatherwood,1 R. Herron,2 A. Flatt,1 and M. Esco1

1Auburn University at Montgomery; and 2The University of Alabama

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Purpose: Heart rate variability (HRV) and heart rate recovery (HRR) are noninvasive indicators of cardiovascular autonomic control and are becoming popular for observing physiological changes associated exercise training and reflecting recovery status. Previous research suggests there is a relationship between HRV and HRR, though the extent of this link remains unclear. Additionally, measuring HRV in different body positions (supine vs. stand [SUP vs. STA]) could further help explain the variance found in HRR following maximal exercise. The purpose of this study was to determine the extent of variation in HRR that could be accounted for by HRV measured in SUP and STA in collegiate-female athletes. Methods: Twenty-three females (height = 1.65 ± 0.06 m, weight = 60.8 ± 6.3 kg,

= 44.6 ± 5.2 ml·kg−1·min−1) participated in this study. Each participant rested in the supine position while HRV was recorded during the last 5-minute of a 10-minute SUP period, followed by an additional 6-minute STA period of which the final 5-minute was analyzed. Participants completed a modified Bruce protocol treadmill exercise test to attain

. Immediately following the exercise test, each subject actively walked at 0.89 m·s−1 and 1.5% grade, while recording HRR at the 1-minute (HRR1) and 2-minute recovery mark (HRR2). HRV values were expressed as root mean of successive R-R interval differences (RMSSD). Pearson-product moment correlations were used to investigate the relationships between the HRR and HRV variables. Results: The STA and SUP values were as follows; RMSSD = 40.4 ± 26.3 ms and 87.17 ± 38.8 ms, respectively. Mean values for HRR1 was 28 ± 11 bpm and for HRR2 was 49 ± 11 bpm. Significant correlations were found for STA and HRR1 (r = 0.54, p = 0.008) and HRR2 (r = 0.48, p = 0.020). However, no significant relationships were found between SUP and HRR1 (r = 0.25, p = 0.255) or HRR2 (r = 0.38, p = 0.073). Conclusions: These results provide evidence that HRR is related to resting parasympathetic modulation when measured in the standing position within collegiate-female athletes. However, no association was found between HRR and supine HRV. Therefore, when compared to the resting supine measures, standing RMSSD appears to be more strongly related to post-exercise vagal return. Practical Application: HRV and HRR are 2 non-invasive markers of cardiovascular autonomic control. Both markers are becoming popular objective measures to consider when monitoring athletic recovery status and physiological adaptation to training. Practitioners need to be aware that resting HRV and HRR may be independently associated with cardiac-autonomic control. Therefore, these measures could reflect different responses to training. Additional research involving longitudinal investigation is needed.

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11. The Acute Effect of Exercise and Nutrition on Energy Expenditure in Women

H. Wingfield,1 A. Smith-Ryan,2 M. Melvin,1 E. Roelofs,2 E. Trexler,2 and A. Hackney3

1University of North Carolina at Chapel Hill; 2The University of North Carolina at Chapel Hill; and 3The University of North Carolina–Chapel Hill

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Background: Few studies exist evaluating metabolic responses to exercise and nutrition in women. Understanding sex-specific physiological responses may improve exercise prescription. Purpose: To examine the effect of exercise modality and pre-exercise carbohydrate (CHO) or protein (PRO) ingestion on resting energy expenditure (REE) in women. Methods: Twenty recreationally active women (Mean ± SD; age 24.6 ± 3.9 years; height 164.4 ± 6.6 cm; weight 62.7 ± 6.6 kg; %fat 28.2 ± 4.8%) participated in this randomized crossover, double-blind study. After preliminary body composition and maximal strength testing, each participant completed 6 exercise sessions, consisting of 3 exercise modalities: aerobic endurance exercise (AEE), high-intensity interval running (HIIT), and high-intensity resistance training (HIRT), and 2 acute nutritional interventions: CHO and PRO. Salivary samples were collected before each exercise session to determine estrogen, and before and after to quantify cortisol. REE was analyzed via indirect calorimetry (Parvomedics TrueOne 2400) at: baseline, immediately post (IP), 30 minutes (30 min) post, and 60 minutes (60 min) post-exercise. Subjects were seated and connected to the metabolic cart by a hose for 15 minutes at each time point. A mixed level model (modality [AEE vs. HIIT vs. HIRT] × treatment [CHO vs. PRO] × time [base vs. IP vs. 30 min vs. 60 min]), covaried for estrogen was used to evaluate REE. Results: There was no 3-way interaction between modality, treatment, and time (p = 0.6336). Significant 2-way interactions were found between modality and time (p < 0.0001) and time and treatment (p = 0.0078), but not between modality and treatment (p = 0.0603). For the modality and time interaction, significant modality differences were found between HIIT and AEE (p < 0.0001), and HIIT and HIRT (p < 0.0001), but not between AEE and HIRT (p = 0.1331). REE was significantly higher as a result of HIIT than AEE at all time points (p = 0.001–0.002). REE was significantly higher for HIIT when compared to HIRT IP exercise (p < 0.0001), but not significantly different at 30 minutes (p = 0.3345) or 60 minutes post (p = 0.1428). For time and treatment, REE was significantly higher for PRO than for CHO at all time points (p < 0.01). There was no significant effect of modality on cortisol (p = 0.168). Conclusions: HIIT produced a higher REE than AEE up to 60 minute post exercise, and a higher REE than HIRT IP exercise. AEE and HIRT produced similar post-exercise REE responses. PRO ingestion prior to exercise significantly increased REE more than CHO ingestion. Practical Application: While HIIT and HIRT had a similar caloric response post-exercise, compared to AEE, HIIT was the most effective and time-efficient approach. Immediately post exercise there was a heightened caloric effect from the HIIT bout stimulating ∼800 kcal/d more than HIRT and AEE. PRO ingestion prior to exercise may help further maximize the caloric effect, with ∼90 kcals/d expended more than CHO. Combinatory effects of HIIT and pre-exercise PRO intake in women is likely to lead to greater changes in weight and body composition as a result of the elevated REE. Acknowledgments: This study was supported by the National Strength and Conditioning Association Foundation.

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12. Gender Differences in the Physiological Responses to a Simulated Crossfit Competition Event

O. Rader, A. Jagim, C. Yoos, R. Meyer, N. Erickson, K. Bykowski, and M. Hornung

Gannon University

*Award Eligible—Undergraduate Student Research Award for an outstanding podium abstract presentation.

Purpose: Previous research has examined the effectiveness of CrossFit training on improving long term training adaptations as well as the relative intensities of individual workouts from a health and fitness perspective. However, there is limited research regarding the physiological demands of CrossFit competitions as a sport and whether or not there are differences between genders. Therefore the purpose of this study is twofold: (a) To assess the physiological responses to a simulated CrossFit competition event; (b) To observe any gender differences in these responses. Methods: Eighteen experienced CrossFit men (n = 10) and women (n = 8) (37.8 ± 10.6 years, 172.8 ± 8 cm, 77.4 ± 13.2 kg, 16.6 ± 6% body fat,) participated in a simulated CrossFit competition event consisting of 3 WODs throughout the course of 1 day. The competition was similar to those used during CrossFit Games. WOD 1 was referred to as “Helen” and consisted of 3 exercises performed in succession with a set number of repetitions for 3 rounds to be completed as fast as possible for time. WOD 2 was a strength WOD during which participants had 5 minutes to find their 1 repetition max for thrusters. WOD 3 was an 11-exercise “chipper” completed as fast as possible. During the competition heart rate, blood lactate, RPE and

data were collected during each WOD and recovery. Data are presented as means ± SD. Results: A 1-way ANOVA revealed a significant difference in time to completion between males (629.7 ± 90.2 seconds) and females (733.1 ± 95.7 seconds) for WOD 1 (p = 0.03) and WOD 3 (males: 395.3 ± 74.8; females: 493.1 ± 45.3 seconds; p = 0.005). There were no significant differences in the percentage of max heart rate (males: 90.9 ± 11.8; females: 94.3 ± 5.3%; p = 0.47) and percentage of

max achieved (males: 85.2 ± 21.7; females: 86.7 ± 9.2%; p = 0.86) by the participants during WOD 1 between males and females. There was a significant difference in the 1RM for thrusters during WOD 2 between males and females (males: 94.1 ± 21.3; females: 51.0 kg; p < 0.001). Analysis revealed no significant differences in the percentage of max heart rate (males: 94.9 ± 3.9; females: 95.7 ± 5.5%; p = 0.73) and percentage of

max achieved by the participants (males: 92.0 ± 5.6; females: 86.3 ± 10.7%; p = 0.20) during WOD 3 between males and females. Males had a significantly greater estimated caloric expenditure during WOD 3 compared to females (males: 17.0 ± 2.2; females: 12.4 ± 5 kcal/min; p = 0.04). There were no significant differences between males and females in changes in lactate values following WOD 1 (p = 0.12), WOD 2 (p = 0.30) or WOD 3 (p = 0.25). Conclusions: These data suggest that a simulated CrossFit competition event is equally challenging for males and females even though the males tended to complete the WOD's in a shorter amount of time and maxed out at heavier weights. Furthermore based on the observed heart rate,

and lactic acid responses during the simulated competition, it can be concluded that CrossFit is a physically demanding sport performed at a high intensity with a great involvement of the anaerobic energy system. Practical Application: Due to the anaerobic nature of the sport, training for a CrossFit competition should focus on stressing the anaerobic energy system, improving muscular endurance and developing strength. It should also be noted that each CrossFit competition selects different WOD's that may consist of more aerobic events or require a high degree of balance and coordination.

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13. The Effect of Massage Therapy on Muscle Recovery Following Downhill Running

T. Allen, B. Church, M. Jones, T. Adams, and J. Stillwell

Arkansas State University

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Purpose: Delayed-onset muscle soreness (DOMS) is sometimes experienced 24–48 hours following unaccustomed eccentric exercise. Methods to alleviate the soreness and decrease in muscle performance associated with DOMS are warranted but have been elusive. The purpose of this study was to determine the effects of massage therapy on the symptoms of delayed onset muscle soreness including torque, range of motion, and muscle soreness as a result 30 minutes of downhill running. Methods: Eighteen physically active males (mean age 23.3 ± 3.8) volunteered to participate in this investigation. The dependent variables measured were soreness using a visual analog scale, range of motion, and flexion and extension peak torque measured by isokinetic dynamometry. Participants ran at a 14% decline for 30 minutes to induce soreness. At 24, 48, and 72 hours after the downhill running, participants returned to the laboratory for follow-up measurements of pain, ROM, and torque. In addition, the participants' dominant leg received 20 minutes of Swedish massage by the primary author, a licensed massage therapist. This approach allowed a leg-to-leg comparison of soreness. A 2 × 4 (leg × time) mixed factorial ANOVA was conducted for soreness, strength, swelling, and range of motion. Results: Participants reported a significant increase in soreness as measured by the visual analog scale following the downhill running (p < 0.00). There was no interaction between the independent variables leg and time, indicating the massage therapy had no significant effect on soreness. Mean soreness ± standard deviation of treatment (T) and control (C) legs at the time intervals 0, 24, 48, and 72 hours post exercise (T0 = 1.3 ± 1.4, C0 = 0.9 ± 1.3; T24 = 4.8 ± 1.7, C24 = 4.9 ± 1.8; T48 = 3.8 ± 2.0, C48 = 4.7 ± 2.2, T72 = 1.9 ± 1.4, C72 = 2.7 ± 1.6). In addition, neither flexion, nor extension peak torque was affected by the massage. Range of motion and swelling was also not influenced. Conclusions: The main finding of this investigation was that the downhill running was sufficient to induce soreness in the participants, and this persisted for at least 72 hours. In addition, the massage therapy had no significant effect on the remaining variables. Also, there was a trend for soreness in the treated leg to decrease over 72 hours post exercise. Statistically significant differences between the treated and the control leg were likely not apparent due to a high degree of variability of the soreness scores among the participants. Practical Application: These results indicate that the Swedish massage used in this investigation did not significantly affect soreness and other measures of performance. Acknowledgments: None.

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14. The Influence of Fall-History Status on Maximal and Rapid Isometric Torque Characteristics in Recreationally-Active Elderly Females

T. Palmer,1 R. Thiele,1 K. Williams,1 B. Adams,1 K. Akehi,2 D. Smith,1 and B. Thompson3

1Oklahoma State University; 2University of Nebraska at Kearney; and 3Texas Tech University

*Award Eligible—Doctoral Student Research Award for an outstanding poster abstract presentation.

A high prevalence of falls in older adults is a major public health concern. Maximal and rapid torque characteristics of the hip extensor muscles play an important role in fall prevention and other balance-related performances and thus, may provide an effective measure for discriminating between elderly females with (“fallers”) and without (“non-fallers”) a history of falls. Purpose: To examine the influence of fall-history status on maximal and rapid isometric torque characteristics of the hip extensors in recreationally-active elderly females. Methods: Six elderly female fallers (mean ± SD: age = 73 ± 7 years; mass = 68 ± 16 kg; height = 160 ± 5 cm) and 9 elderly female non-fallers (71 ± 7 years; 66 ± 16 kg; 157 ± 6 cm) performed 2 isometric maximal voluntary contractions (MVCs) of the hip extensor muscles. For each MVC, participants laid supine with the knee- and ankle-joints immobilized using custom-built stabilizing apparatuses. All MVCs were performed on the right leg at a hip joint angle of 20° above the horizontal plane, while the waist and left thigh were secured with restraining straps. Participants were instructed during each MVC to extend the thigh “as hard and fast as possible” towards the floor against a load cell attached immediately posterior to the heel for 3–4 seconds. Isometric MVC peak torque (PT; Nm) was determined as the highest mean 500 ms epoch during the entire 3–4 seconds MVC plateau. Absolute rate of torque development (RTD; Nm·s−1) was determined from the linear slope of the torque-time curve over the time intervals of 0–50 (RTD50) and 100–200 (RTD100–200) ms relative to the onset of torque production (4 Nm). The absolute torque-time curve was also normalized to PT, from which relative RTD values (%MVC·s−1) were calculated for the same 0–50 (RTD50norm) and 100–200 (RTD100–200norm) ms epochs used to calculate absolute RTD. Results: There were no differences between groups for age, height, or mass (p = 0.470–0.846). The non-fallers exhibited greater absolute and relative RTD for RTD50 (p = 0.039) and RTD50norm (p = 0.011) compared to the fallers; however, there were no group-related differences for PT (p = 0.160) and absolute and relative RTD for RTD100-200 (p = 0.573) and RTD100–200norm (p = 0.565) (Figure 1). Conclusions: These results suggest that during isometric hip extension, early rapid torque characteristics (RTD50 and RTD50norm) were greater for the non-fallers compared to the fallers, despite no differences between groups for maximal and later rapid torque characteristics (PT, RTD100–200, and RTD100–200norm) or anthropometric measurements. Practical Application: Early rapid torque characteristics of the hip extensors may be sensitive and effective measures for discriminating between elderly female fallers and non-fallers. These findings may provide important insight regarding implications for the assessment of fall risk and in the development of proper training programs aimed at minimizing the occurrence of falls and other balance-related injuries in the elderly.

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15. The Influence of Age on the Muscle and Tendon Contribution During Constant Torque Stretching

M. Scharville,1 E. Ryan,2 E. Sobolewski,2 J. Rosenberg,3 A. Tweedell,2 and C. Kleinberg2

1University of North Carolina at Chapel Hill; 2The University of North Carolina at Chapel Hill; and 3University of the North Carolina at Chapel Hill

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Purpose: Constant torque (CT) stretching may be more beneficial than traditional static stretching as it elicits more work on the muscle-tendon unit (MTU), thus increasing joint range of motion. An increase in range of motion is accompanied by a lengthening of the MTU. However, the contribution from the muscle and tendon has yet to be quantified. The purpose of this study was to examine the influence of age on the behavior of the muscle and tendon during a single bout of CT stretching. Methods: Eighteen younger (mean ± SD age, 19.8 ± 2.4 years; stature, 174.7 ± 6.6 cm; mass, 71.5 ± 9.2 kg) and 16 older (age, 68.8 ± 2.9 years; stature, 175.9 ± 3.8 cm; mass, 83.0 ± 11.4 kg), healthy and recreationally active males volunteered for this investigation. Participants visited the laboratory on 2 separate occasions. During familiarization, each participant identified his maximal tolerable torque threshold on a calibrated isokinetic dynamometer. During the experimental visit, each participant performed a 60-s CT stretch at their individualized torque threshold. MTU length was derived from a cadaver regression equation. Muscle and tendon lengths were measured using ultrasonography pre- and post-stretch from the amount of displacement of the myotendinous junction relative to a hypoechoic marker placed between the skin and ultrasound probe. Position changes were examined using an electrogoniometer fixed on the skin at the distal fibula and lateral aspect of midfoot. Four separate mixed factorial analyses of variance (group × time) were used to analyze the differences in ankle joint position and the length of the MTU, medial gastrocnemius (MG), and Achilles tendon (AT). Further, the amount of change from pre-to post-stretching was examined with an analyses of covariance using the pre-stretch values as the covariate. Results: All raw values are listed in the table below. The young men experienced a non-significant (p = 0.072) greater increase (2.01°) in ankle joint position from pre-to post-stretch when compared to the old men (1.41°). MTU length increased for both young and old (p ≤ 0.001), however the younger men experienced a greater increase in MTU length (p = 0.043). Furthermore, the muscle and tendon increased from pre-to post-stretch for both groups; however the muscle lengthened more in the young (p ≤ 0.001), and the tendon lengthened more in the old (p ≤ 0.001). Conclusions: The young men experienced greater increases in ankle joint position and MTU length during a 60-s CT stretch with the muscle increasing to a greater extent in the young (ΔMG length—77%; ΔAT length—23%) and the tendon increasing more in the old (ΔMG length—36%; ΔAT length—64%). These findings may be due to the age-related increases in tendon compliance and muscle stiffness. Practical Application: The results of this study may help clinicians and practitioners better understand the influence of aging on muscle-tendon behavior during common stretching routines.

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16. The Influence of Vibration on the Stretch Induced Strength Deficit

E. Sobolewski,1 E. Ryan,1 J. Rosenberg,2 and M. Scharville3

1The University of North Carolina at Chapel Hill; 2The University of North Carolina–Chapel Hill; and 3The University of North Carolina–Chapel Hill

*Award Eligible—Doctoral Student Research Award for an outstanding poster abstract presentation.

Previous studies have demonstrated an acute bout of prolonged stretching results in the stretch-induced strength deficit which have been explained by mechanical and/or neurological factors. Recent literature using short bouts of muscle vibration has reported increases in muscle spinal sensitivity and muscle activation, thus it may be possible that the stretch-induced strength deficit may be offset with locally applied vibration. Purpose: The purpose of this study was to examine the effects of locally applied vibration applied during passive stretching on the maximal isometric strength and muscle activation. Methods: Thirty-three healthy males (mean ± SD: age = 21 ± 2 years), performed maximal isometric voluntary contractions (MVC) of the plantar flexors on a calibrated dynamometer at 90° between the leg and the foot prior to and following three 1-minute passive constant-torque (CT) stretches with and without locally applied vibration. The local vibration was applied to the Achilles tendon at 60 Hz with 1 mm peak to peak amplitude. The order of conditions was randomized. Electromyographic (EMG) electrodes where placed over the belly of the medial gastrocnemius to monitor muscle activity. The same 500 ms epoch that was used to calculate peak torque (PT) was used to determine peak EMG amplitude and normalized to pre-stretching values. A 2 × 2 (condition × time) repeated measures ANOVA was performed for PT and normalized EMG amplitude. A type-1 error rate of 5% was used to determine statistical significance. Results: For PT, there was no interaction (p = 0.444) or main effect for condition (p = 0.571) but there was a time (p = 0.024). For normalized EMG amplitude there was no interaction (p = 0.795), and no main effects for condition (p = 0.795) or time (p = 0.093). Conclusions: Both conditions resulted in a significant decline in PT (∼3 Nm) after stretching; however there was no change in normalized EMG amplitude. These data suggest that short practical durations of CT stretching result in significant but minor reductions in PT that were unaffected by locally applied vibration. In addition, these results may indicate that the decline in strength following shorter durations of stretching may be due to mechanical factors (i.e., reduction in passive stiffness) vs. changes in muscle activation. Practical Application: Stretching alone prior to events that require maximal strength is not recommended, but in light of these findings stretching paired with an (dynamic) activity aimed at returning the muscle tendon unit to a pre stretch state (length) may be beneficial based on the deficit tending to be more mechanical in nature.

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17. Effects of the Army Physical Fitness Training on Physical Performance Characteristics in Freshmen Army Reserve Officer Training Corps (ROTC) Cadets

C. Holt,1 S. Jenke,1 A. Kreutzer,1 L. Brace,1 M. Jones,2 and J. Oliver1

1Texas Christian University; and 2George Mason University

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

The Army Physical Readiness Training (APRT) is widely used to train Reserve Officers' Training Corp (ROTC) cadets across collegiate campuses. The Army has begun to recognize the importance of strength and power as components of military fitness. However, the current APRT is limited to training that focuses primarily on aerobic capacity and activities associated with the Army Physical Fitness Test (APFT), including calistenics and body weight resistance. To what effect APRT has on measures of strength and power in ROTC cadets is unknown. Purpose: Therefore, the purpose of the current study was to determine the effect of APRT on specific physical and performance characteristics related to strength and power of entering freshmen cadets over the course of a semester. Methods: Thirteen ROTC cadets (7 male, 6 female; mean ± SD; age = 18.58 ± 0.36 years; height = 171.0 ± 14.0 cm; body mass = 70.9 ± 11.5 kg; body fat = 24.6 ± 8.4%) participated in APRT 3 days a week for 16 weeks (48 total sessions). Cadets had their body composition assessed (dual-energy x-ray absorptiometry) and completed a series of performance tests before (PRE) and after (POST) the 16-week APRT. Performance tests included maximal oxygen consumption (

), power output during a counter movement vertical jump (CMVJ), one repetition maximum (1RM) bench press (BP) and back squat (BS), and the APFT: 2 minutes maximum pushups (PU) and sit-ups (SU), and timed 2 mile run (2M). Statistical analyses included mean, SD, and paired t-test (p ≤ 0.05).Results: No changes were observed in body mass (p = 0.752), body fat (p = 0.707), or lean mass (p = 0.155). Both 1RM BP (PRE, 61.5 ± 20.8 kg; POST, 67.0 ± 21.9 kg; p = 0.001) and 1RM BS (PRE, 84.6 ± 32.8 kg; POST, 92.8 ± 29.6 kg; p = 0.017) improved following training. No improvements were observed in power output as determined by CMVJ (PRE, 1074 ± 243 W; POST, 1101 ± 221.5 W; p = 0.179). APFT 2M time decreased (PRE, 16.5 ± 2.8 minutes; 15.7 ± 1.9 minutes; p = 0.03) despite a decrease in

(PRE, 46.8 ± 9.5 ml·kg·min−1; POST, 43.1 ± 6.6 ml·kg·min−1; p = 0.03). APFT PU (PRE, 38 ± 17; POST, 50 ± 19; p = 0.001) and SU (PRE, 56 ± 16; POST, 71 ± 11; p = 0.001) scores improved following training. Conclusions: Significant improvements in strength failed to elicit changes in total lean body mass, likely due to early phase neurological adaptations to resistance training in relatively untrained freshmen cadets. Significant improvements in lower body strength did not improve power output. This was an expected outcome due to the lack of power focused exercise in standardized APFT training. The decrease in

with concomitant decrease in 2M suggests improved time was not a result of improved aerobic fitness. Practical Application: Incorporation of training exercises designed to improve strength and power into APRT programming for ROTC cadets is recommended. Given the role ROTC cadets assume post graduation, incorporation of such exercises may contribute to increased awareness and leadership within unit.

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18. Incidence of Hallucinations During an Ultra-Endurance Event

C. Riley,1 A. Pearson,1 T. Piper,1 C. McMillan,1 D. Bellar,2 and J. Decker3

1Western Illinois University; 2University of Louisiana at Lafayette; and 3Gut Check Fitness

*Award Eligible—Undergraduate Student Research Award for an outstanding poster abstract presentation.

Purpose: The purpose of this study was to examine whether or not hallucinations occur when athletes undergo extreme physical exertion for extended periods of time without sleep. Methods: Twenty-two participants (Male = 15, Female = 7; Mean Age = 31.9 ± 8.66 years; Age Range = 19–58) enlisted in the event were surveyed with a questionnaire asking, “Do you feel like you may have experienced anything that might be a hallucination?” every time they checked in after finishing a race event. If the participants answered “Yes,” then there was a follow up question asking the participants to explain what they experienced. Subjects' frequency of training prior to the event was under 3 days per week (M = 2.81 ± 0.81) with training session length varying from 90 minutes to 1200 minutes (M = 352.62 ± 293.77). The official title of the event was “The Ultimate Suck,” and the race consisted of a wide range of challenges and obstacles with no specific emphasis on one discipline of fitness. This event was 36 hours in duration. “The Suck” is a military term that defines any situation where conditions are undesirable and is a testament to the dedication of those who endure it. Results: The overall result of the hallucination questionnaire was that 30 experiences occurred in total. Within those hallucinations, 11 could possibly be explained by a misperception of something in actual existence. However 19 hallucinations could not be explained in this way. The highest frequency of hallucinations was recorded between the 28th and 30th hour of participation. Conclusions: This study revealed that participants going through intense exercise in concurrence with sleep deprivation may experience hallucinations after a prolonged time. After reviewing the literature, this study also concluded that the addition of extreme physical exertion to prolonged wakefulness and sleep deprivation may accelerate the arrival of psychotic symptoms. Practical Application: When considering the types of training that military, police and other first responders are put through, and the situations in which they are to operate in, it is important to know when they could possibly become a danger to themselves, as well as the people around them. Having an idea as to when these tactical athletes may become unfit for duty can potentially reduce the occurrence of fatal mistakes made in the line of duty.

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19. Examination of a Novel Test of Upper Body Isometric Strength

L. Marcus,1 D. Bellar,1 M. Breaux,1 and L. Judge2

1University of Louisiana at Lafayette; and 2Ball State University/School of PE, Sport, and Exercise Science, Muncie, IN

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Purpose: The purpose of the present investigation was to examine the association of a novel test of upper body isometric strength against a 1RM bench press measurement. Methods: Thirty-two college age adults (n = 18 female, n = 14 male; mean ± SD; Age 22.8 ± 2.9 years; height 171.5 ± 11.2 cm; weight 71.4 ± 15.7 kg; body fat 23.6 ± 5.0%) volunteered for the present investigation. The participants reported to the lab on 3 occasions. The first visit included anthropometric measurements and familiarization with both the upper body isometric test along with 2 practice sets of bench press exercise where technique was evaluated. The final 2 visits were conducted in a randomized order, with one being a 1RM assessment on the bench press and the other consisting of 3 trials of the novel upper body isometric assessment. Grip width was held constant at 150% of biacromial width for both the bench press and isometric test. For the isometric test, participants were positioned in such a manner to create 90 degrees of elbow flexion, a flat back and 150% of biacromial width in a “push-up” style position while tethered (stainless steel chain) to a load cell (high frequency) anchored to the ground. The participants were instructed to push-up against the chain as hard as possible, and were not allowed to start with any slack in the chain. The peak isometric force was recorded for each of the 3 trials separated by 5 minutes of recovery. The peak result of the 3 trials was used for subsequent analysis Results: Multiple regression analysis was completed with the predictors: peak isometric force, gender, body weight against the outcome variable 1RM bench press. The analysis resulted in a significant model (r2 = 0.868, p ≤ 0.001) with all predictor variables attaining significance in the model (p ≤ 0.05). Isometric peak strength had the greatest effect on the model (t = 5.08, p ≤ 0.001). Conclusions: Results from this study suggest that the novel isometric upper body strength assessment is likely to be a valid tool to determine strength. Further research is warranted to gather a larger pool of data in regard to this assessment. Practical Application: This study provides coaches with a quick and effective tool to collect strength data that is strongly associated with strength in the bench press movement. The equipment for this test is not cost prohibitive and practitioners could examine this as a time efficient alternative to conducting 1RM bench press assessments in large groups.

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20. Quadriceps Cross Sectional Area Correlates With Dynamic Peak Torque but Not as a Percent of MVIC

K. McLeland,1 L. Brown,2 J. Coburn,2 and A. Galpin2

1Center for Sport Performance, California State University, Fullerton; and 2California State University, Fullerton

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Assumptions have been made that the ability to produce dynamic and isometric torque are similar. Larger muscles produce more force, however, different types of muscle actions can exhibit dissimilar characteristics. When designing strength programs, it is important to integrate specificity. Training isometrically for a dynamic activity may have less carryover to dynamic performance. Purpose: The purpose of this study was to compare quadriceps muscle cross sectional area and both dynamic peak torque (DPT) and DPT as a percentage of peak isometric torque (MVIC). Methods: Nine resistance trained men (age = 25.4 ± 1.6 years; height = 179.7 ± 5.6 cm; mass = 89.6 ± 11.1 kg) volunteered and had their right thigh circumference (61.9 ± 4.3 cm) and skin fold (15.7 ± 6.5 mm) measured in order to estimate cross-sectional area (CSA = 91.2 ± 7.6 cm2) using the Housh Equation. Subjects were then seated on a Biodex isokinetic dynamometer and performed a MVIC at 60 degrees of extension. Following 2 minutes rest, they performed a maximal knee extension at 180° per second, measuring dynamic peak torque. Results: CSA and DPT (232.5 ± 31.0 N/m) were highly correlated (r = 0.818), but CSA and MVIC (332.2 ± 51.1 N/m) were only moderately (r = 0.512) correlated. There was no significant correlation of CSA and DPT as %MVIC (Range = 48.15–93.1%; mean = 70.6% ± 7.8; r = 0.177). Conclusions: CSA of the quadriceps has a greater correlation with maximal DPT as opposed to MVIC. Additionally, CSA and %MVIC that is produced in DPT have no significant relationship. Since there was no significant correlation between CSA and %MVIC, muscle size is not a significant determinant of dynamic torque. A.V. Hill described the relationship between torque and velocity through a curvilinear relationship. These results show individual differences in the slope of that curve, not just a relative shift right based on maximal torque production. Practical Application: In developing training programs, more emphasis should be placed on performing maximal dynamic concentric actions as opposed to isometric muscle actions. Since sport is a dynamic activity, the principle of specificity is highly applicable when training athletes. The results of this study support that having a larger quadriceps muscle cross-sectional area will improve torque of a dynamic activity. It also demonstrates that maximal isometric torque may not determine how much dynamic torque can be produced. This also demonstrates that the torque-velocity relationship changes based on the individual athlete. Strength and velocity training should be tailored to athletes depending on their ability to produce dynamic torque at higher speeds, in turn, increasing their power.

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21. Barbell Deadlift Training Increases the Rate of Torque Development and Vertical Jump Performance in Novices

J. Mota, B. Thompson, K. Olinghouse, E. Carrillo, I. Munayer, M. Luera, J. Shields, A. Drusch, and M. Stock

Texas Tech University

*Award Eligible—Undergraduate Student Research Award for an outstanding poster abstract presentation.

The barbell deadlift is a multi-joint exercise that requires balance, strength, and the coordination of dozens of muscles. No previous studies have examined the effectiveness of barbell deadlift training when performed in the absence of other exercises. Purpose: The primary purpose of this investigation was to examine the effects of 10 weeks of barbell deadlift training on rapid torque characteristics for the leg extensors and flexors. A secondary aim was to analyze the relationships between training-induced changes in rapid torque and vertical jump performance. Methods: Fifty-four previously untrained subjects (mean ± SD age = 23 ± 3 years) participated in this investigation, and were randomly assigned to a training (males, n = 17; females, n = 17) or control (males, n = 9; females, n = 11) group. The subjects in the training group were taught how to deadlift, and performed 5 sets of 5 repetitions twice per week. Each training session was closely supervised, and 0.45–2.2 kg was added to the barbell during each visit to the laboratory. All subjects performed maximal isometric strength testing of the left leg extensors and flexors, as well as maximal countermovement vertical jumps, before and following the intervention. Torque -time curves were used to calculate rate of torque development (RTD) values at peak and 50 and 200 ms from torque onset. Results: Barbell deadlift training induced significant pre to post increases of 18.8–49.0% for all rapid torque variables (Table 1). For the subjects in the training group, the largest effect size shown was for RTD at 50 ms for the leg flexors (pre = 199.6 ± 94.6, post = 297.5 ± 98.8 Nm·s−1 [Cohen's d = 1.01]). Vertical jump height increased from 46.0 ± 11.3 to 49.4 ± 11.3 cm (Cohen's d = 0.30) for the subjects in the training group, and these changes were correlated to improvements in RTD for the leg flexors (r = 0.30–0.37). Conclusions: When performed in the absence of other exercises, 10 weeks of barbell deadlift training enhanced the rapid torque characteristics for both the leg extensors and flexors. Changes in rapid torque were associated with improvements in vertical jump height, suggesting a transfer of adaptations from deadlift training to an explosive, performance-based task. Practical Application: Since many activities of daily living require the legs, hips, and low back to function together in a coordinated manner during the act of picking up an object from the ground, the functionality of the barbell deadlift has implications for a variety of populations. Strength and conditioning professionals are encouraged to emphasize the barbell deadlift exercise when attempting to design training programs with the intent to develop explosive strength and/or jumping performance in novices.

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22. Weighted Post-Set Stretching Increases Skeletal Muscle Hypertrophy

J. Silva,1 R. Lowery,2 J. Antonio,3 S. McCleary,1 J. Rauch,1 J. Ormes,2 K. Shields,2 M. Sharp,2 J. Georges,2 S. Weiner,2 J. Joy,2 and J. Wilson2

1University of Tampa; and 2University of Tampa Human Performance Lab, 3Nova Southeastern University

*Award Eligible—Undergraduate Student Research Award for an outstanding poster abstract presentation.

Previous research using the avian stretch model has demonstrated profound skeletal muscle hypertrophy and hyperplasia. Purpose: To investigate the effects of weighted intraset stretching on skeletal muscle size and strength in human subjects. Methods: Twenty-four recreationally trained subjects (20 ± 2.0 years of age) were randomly assigned to stretching and non-stretching conditions. In both conditions subjects performed 4 sets of 12 repetition calf raises on a leg press twice a week for 5 weeks. The first set was performed at 90% of subjects 1-RM, followed by 3 sets in which the weight decreased by 15% of subjects 1-RM per set. Between sets the stretching group allowed the weight on the leg press to stretch the gastrocnemius for 30 seconds before continuing, while the non stretch condition held the weight stack with their feet neutral and not stretched. Gastrocnemius muscle thickness was determined pre and post via ultrasonography. Results: There was a significant group × time effect (p ≤ 0.05) for muscle thickness in which the delta change was greater in the stretching vs. non stretching condition (+23 ± 5.0 vs. + 9 mm ± 4.8). There were time (p ≤ 0.05) effects for strength in which both the stretching (+49.7 ± 8.0 kg) and non stretching (+37.1 ± 7.0 kg) increased in strength, with no differences between conditions. Conclusions: Intraset stretching may increase skeletal muscle hypertrophy when combined with resistance training. Practical Application: Athletes interested in inducing skeletal muscle hypertrophy can implement intraset stretching into their regimens.

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23. Acute Effects of Assisted Jumping on Muscle Activation

T. Beaudette,1 L. Brown,2 J. Coburn,2 S. Lynn,2 and D. Dunnick1

1CSU Fullerton Center for Sport Performance; and 2California State University, Fullerton

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Introduction: Recent research has shown assisted jumping results in an acute performance enhancement of a subsequent bodyweight vertical jump (VJ). It is hypothesized that this enhancement may be due to an increase in muscle activation. However, measurement of muscle activation has not been recorded post assisted jumping in an effort to better understand the mechanism underlying enhanced performance. Purpose: The purpose of this study was to investigate lower body muscle activation during a bodyweight VJ following assisted jumping. Methods: Nine NCAA collegiate women's volleyball players (19.11 ± 1.05 years; 175.99 ± 7.52 cm; 75.47 ± 10.88 kg) completed 2 experimental conditions (bodyweight and assisted jumps). Following each condition, participants performed 3 bodyweight countermovement VJ separated by 15 seconds rest. During assisted jumping participants wore a climbing harness with elastic cords attached to their hips, then stretched to the ceiling by a rope. In both conditions participants performed 5 plyometric countermovement VJ with either 0% bodyweight reduction or 40% bodyweight reduction depending on the trial. Following both conditions, participants rested for 1 minute then performed 3 individual bodyweight countermovement VJ separated by 15 seconds rest. EMG was used to measure RMS in the gluteus maximus (GL), vastus lateralis (VL), and gastrocnemius lateralis (GC) during the eccentric and concentric phases of the countermovement prior to take off. Results: There was no main effect for condition. However, there was an interaction (p ≤ 0.05) of muscle x action. For eccentric, VL (0.10 ± 0.02 mV) and GC (0.13 ± 0.04 mV) were greater than GL (0.01 ± 0.00 mV), and GC was greater than VL. For concentric, VL (0.43 ± 0.08 mV) was greater than GL (0.12 ± 0.04 mV) and GC (0.31 ± 0.10 mV), while GC was greater than GL. Conclusions: No main effect for condition suggests that the assisted jumping stimulus was not strong enough to elicit differences in muscle activation. Testing experienced jumpers may have also minimized the physiological adaptation that might have occurred when compared to inexperienced jumpers. Differences in the pattern of muscle activation between actions might mean that participants had a backward trunk lean creating a knee dominant position during the eccentric phase of the countermovement, but this cannot be concluded without kinetic data. Practical Application: These findings do not support acute increases in muscle activation post assisted jumping in experienced jumpers. It is possible that jump kinematics play a role in the pattern of muscle activation. Assisted jump research would be enhanced by reporting these variables along with muscle activation. The use of trained vs. untrained participants may have an effect on the acute implementation of assisted jumping, and should be investigated further.

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24. The Relationship Between Serum Testosterone and Measures of Strength and Power

T. Johnson,1 S. Jenke1, L. Brace1, A. Kreutzer1, C. Holt1, M. Jones2, and J. Oliver1

1Texas Christian University; and 2George Mason University

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Testosterone (TEST), the primary male hormone, has been shown to correlate with measures of lower body power in elite athletes. However, this relationship has not been demonstrated in recreational athletes. Given elite athletes are known to have a higher percentage of type II muscle fibers than other athletes, it is of interest to determine if the relationship of TEST and power is due to total TEST, or other factors such as muscle composition. Purpose: The purpose of the current study was to determine the correlation between basal levels of total TEST and measures of lower body strength and power in recreational lifters. Methods: Thirty males (mean ± SD; 26.1 ± 4.5 years; 176.8 ± 6.9 cm; 84.9 ± 11.5 kg; 15.1 ± 6.2% body fat) with ≥1 year back squat (BS) experience and a one-repetition maximum (1RM) BS to body mass ratio of >1.5 participated in this study. Following an overnight fast (≥8 hours) participants had their blood drawn for measurement of total TEST, and body composition assessed by 7-site skin fold measurement. After skin fold measurement, participants completed a standardized warm up followed by the performance of the standing long jump (SLJ), counter movement vertical jump (CMVJ), and 1RM BS for determination of lower body strength. Body mass and CMVJ height were used to calculate lower body power output in watts (W). Participants were allowed 3 attempts each for SLJ and CMVJ. If the third was greater, another attempt was allowed until a decrease was observed. No more than 5 attempts were performed. Bivariate (Pearson) correlations were computed to determine significance (p ≤ 0.05). Moderate correlations were defined as R-values of 0.41–0.70, and strong correlations were considered to be between 0.71 and 0.90. Results: The 1RM BS-to-body-mass ratio was 1.80 ± 0.2. Total TEST was 987 ± 288 pg/dl. There were moderate correlations between lean mass and CMVJ (r = 0.697; p = 0.001), and between lean mass and 1RM BS (r = 0.556; p = 0.003). A significant correlation was observed between SLJ and 1RM BS, which were scaled to height and body mass, respectively (r = 0.416; p = 0.022). Power output as measured by CMVJ was strongly correlated to 1RM BS (r = 0.736, p = 0.001). There were no correlations between basal testosterone and any physical performance measure (SLJ, r = −0.032; CMVJ, r = −0.189; 1RM BS, r = −0.197). Conclusions: The results of the current study suggest lower body strength is strongly correlated with lower body power output in recreational lifters. Further, a relationship exists between lean body mass and measures of strength and power. The positive relationship between testosterone and jumping ability previously shown in elite athletes was not observed in the recreational athletes in the current study. Practical Application: Training programs designed to improve lower body strength and increase lean body mass will have a positive effect on standing long jump and countermovement vertical jump performance.

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25. An Electromyographic and Force Plate Analysis of the Deadlift Performed With and Without Chains

R. Nijem,1 J. Coburn,2 L. Brown,3 S. Lynn,2 and A. Ciccone2

1Rocky Mountain University of Health Professions; 2CSU Fullerton Center for Sport Performance; and 3California State University, Fullerton

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

The use of chains as variable resistance is popular with a great deal of anecdotal support, yet research evidence is limited. Purpose: The purpose of this study was to determine the effects that chain variable resistance has on surface electromyography (EMG) of the erector spinae (longissimus), gluteus maximus, and vastus lateralis, ground reaction forces (GRFs), and rate of force development (RFD). Methods: Thirteen resistance trained men (24 ± 2.1 years, 179 ± 4.8 cm, 87.0 ± 10.6 kg) volunteered for the study. On day 1, subjects performed 1 repetition maximum (1RM) testing of the deadlift exercise. On day 2, subjects performed one set of 3 repetitions with a load of 85% 1RM with chains (CH) and one set of 3 repetitions without chains (NC). The order of the CH and NC conditions was randomly determined for each participant. For the CH condition, the chains accounted for approximately 20% (19.9 ± 0.6%) of the 85% 1RM at the top of the movement. EMG was recorded to differentiate muscle activity between conditions (CH, NC), range of motion (ROM; bottom half, top half) and phases (concentric, eccentric). Peak GRFs and RFD were measured using a force plate. Results: For the gluteus maximus there was significantly greater EMG activity (p ≤ 0.05) during the NC condition vs. the chain condition. In addition, the concentric phase resulted in significantly greater EMG activity (p ≤ 0.05) than the eccentric phase. EMG results for the erector spinae (longissimus) revealed that the bottom ROM had significantly greater (p ≤ 0.05) EMG activity than the top ROM, while the eccentric phase produced significantly greater EMG vs. the concentric phase. EMG results for the vastus lateralis revealed significantly greater EMG (p ≤ 0.05) activity for the concentric vs. eccentric phase. Force plate results revealed that deadlifting at 85% 1RM with an accommodating chain resistance of approximately 20% results in a reduction in RFD and GRFs (p ≤ 0.05). Practical Application: Collectively, these results suggest that the use of chains can alter muscle activation and the force-time characteristics of the deadlift.

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26. Effects of Pre-Event Massage on Speed in Collegiate Sprinters

I. Pena, A. Cho, L. Brown, J. Coburn, and S. Lynn

California State University, Fullerton

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Massage is one of the oldest existing therapies utilized within the medical community. The practice of massage has become more widespread as the modern era emerged with specific techniques being used to treat the respective body systems. The effect of massage on athletic performance is a controversial topic within sports medicine. Swedish massage is the technique widely used in current research, which is popularly known as a relaxation technique. Another technique is pre-event sports massage, which is utilized to stimulate the body prior to athletic performance. Little to no research has examined the effect of pre-event sports massage on athletic performance. Purpose: The purpose of this study was to determine the effects of pre-event sports massage (SP) vs. Swedish massage (SW) on speed in collegiate sprinters. Methods: Twelve collegiate offseason male and in season female sprinters (19.4 ± 1.16 years) completed maximal 40 m sprints under 3 different conditions: baseline, SP, and SW. Results: There was no main effect of massage on speed. There was a main effect of gender where men were significantly faster (baseline 4.97 ± 0.12, Swedish massage 5.00 ± 0.10, pre-event massage 4.97 ± 0.10) compared to women (baseline 5.61 ± 0.18, Swedish massage 5.67 ± 0.19, pre-event massage 5.73 ± 0.14). Conclusions: These results suggest that there was no effect of either pre-event sports massage or Swedish massage on speed. Additionally, there was no detriment to performance through the use of pre-event sports massage. Practical Application: Massage is popularly used in athletics. This study shows that the use of SP does not hinder athletic performance, and if massage is part of an athletic team's program, there may be a psychological benefit involved for those athletes. Further research is needed related to how different durations and styles of massage affects speed.

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27. Effects of Caloric Load on Resistance Training Adaptations in Strength and Power

K. Shields,1 S. McCleary,2 M. Sharp,1 J. Ormes,1 J. Rauch,2 J. Silva,2 J. Joy,1 J. Georges,1 S. Weiner,1 R. Lowery,1 and J. Wilson1

1University of Tampa Human Performance Lab; and 2University of Tampa

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

Athletes across a number of sports and athletic disciplines find themselves in an endless search for new and effective methods of increasing neuromuscular function (e.g., strength and power). One method concerns the modulation of calorie intake with athletes attempting to increase strength and power by consuming an extremely high caloric surplus. However, to date the dose response of overfeeding remains to be investigated. Purpose: To investigate the effects of 5 weeks of moderate and high overfeeding on strength and power. Methods: Fourteen recreationally trained athletes were recruited for this study. Individuals were assigned to increase their calories by a moderate (825/calories per day, Pursuit Rx) or a high (2,280 calories per day, Honeyville Whey Concentrate and Maltodextrin Blend) amount of calories in addition to their habitual daily food intake. Subjects performed full body resistance training twice a week for a 5-week period. Wingate peak power, vertical jump peak power, bench press 1RM, and squat 1RM were measured at weeks 0 and 5 of the study. Results: Vertical jump power increased in the moderate group (117.1 ± 77.8 watts) but not in the high group (−6.8 ± 84.6 watts). Wingate power increased in both moderate (82.8 ± 59.4 watts) and high (101.8 ± 87.4 watts) groups. Finally strength increased equally in the squat and bench press. Conclusions: These results suggest that moderate overfeeding combined with resistance training results in more favorable changes in relative dynamic power than high overfeeding, with no differences in any other performance variable. Practical Application: Athletes looking to gain mass and maintain relative power should do so cautiously. Based on our data, athletes should consume moderate excess calories if looking to add strength and power.

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28. Salivary Biomarker Monitoring of Elite Collegiate Female Basketball Players Across an NCAA Division I Season

M. Andre,1 A. Fry,2 A. Hudy,2 P. Dietz,2 and G. Cain2

1University of Wisconsin–LaCrosse; and 2University of Kansas

The ratio between testosterone and cortisol (TC) has been used to monitor training stress and performance in athletes. Purpose: To monitor free testosterone (T), cortisol (C), and the ratio of testosterone to cortisol (TC) in elite female NCAA Division I basketball athletes, weekly, throughout an entire season. Methods: Ten athletes gave a salivary sample before an afternoon practice in the middle of each week for 29 consecutive weeks, beginning in the pre-season and ending 1 week after the end of post-season competition. Salivary samples were assayed for T and C. Additionally, a composite value composed of Z-scores (COMP) for weekly practice minutes, game minutes, resistance training repetitions, academic stress, and travel stress was used in an attempt to quantify weekly cumulative stress so that an increase in COMP suggested an increase in cumulative stress. One-way RM ANOVA with LSD pairwise comparisons were used to determine which weekly values were different (α = 0.05) from the season average. Results: For T, 4 weeks were different from baseline (6.5 nmol/L). For C, 4 weeks were different from baseline (9.0 nmol/L). For TC, weeks 6 (p = 0.004), 16 (p = 0.024), 24 (p = 0.003), and 27 (p = 0.008) were significantly different from baseline (TC = 0.42). During week 6, 1 week prior to the first exhibition game, TC was below baseline and corresponded with an increase in COMP. However, TC returned to baseline by week 7, which was the first week of exhibition play. During week 16, which was collected the week after holiday break, TC was below baseline despite a decrease in COMP. During week 24, TC was below baseline and corresponded with an increase in COMP. During week 27, which was collected immediately before the team's first match of the NCAA tournament, TC was below baseline and corresponded with a decrease in COMP. However, the athletes returned to baseline during the tournament and remained at baseline up to and beyond their fourth round elimination. Conclusions: While these athletes experienced significant decreases in TC throughout the season, the overall hormonal profile appeared to remain stable compared to baseline despite constant variation in cumulative student-athlete stress and also suggested that the athletes were able to return to hormonal baseline by the end of the season. Practical Application: The methods of this study can be used for monitoring fatigue management by assessing how one's athletes adapt to stressful pre-season training and whether or not they recover in time for regular season play, in addition to how the athletes handle the stressors of the competitive season, and is useful for female athletes. Acknowledgments: This study was supported by a KU General Research Fund Award # 2301776.

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29. Comparing Heart Rate Variability Mean Values From 7, 5, and 3 Days in a Team of Female Collegiate Soccer Athletes

A. Flatt and M. Esco

Auburn University at Montgomery

Purpose: The purpose of this study was to determine if the mean value of 5 and 3 days per week heart rate variability (HRV) recordings from both supine and standing positions would accurately reflect the weekly mean value in collegiate female soccer players during spring season training. Methods: Twelve female soccer players (height = 165.12 ± 5.32 cm; weight = 60.78 ± 6.00 kg; body fat = 27.3 ± 4.98;

= 46.08 ± 3.14 ml·kg−1·min−1) recorded their HRV with a smart phone application, a wireless ECG receiver and a chest-strap transmitter each morning for a 1 week period during a spring season strength and conditioning cycle. The participants first performed a supine followed by a standing measurement after waking and elimination. Upon completion of their morning HRV recordings, each athlete manually exported their data to a spreadsheet via the smart phone application to the investigator for analysis. The HRV parameter that was evaluated by the application was the natural log transformed root mean square of successive normal-to-normal interval differences multiplied by 20 (lnRMSSDx20) from a 55-seconds recording. Weekly (7 days) mean values were calculated for each athlete for the supine and standing lnRMSSDx20 measures. Thereafter, mean values were gathered from Monday through Friday for the 5 days recordings and Monday, Wednesday and Friday for the 3 days recordings. Agreement between the 5 and 3 days mean lnRMSSDx20 values and the weekly mean values were determined with repeated measures analysis of variance, intraclass correlations (ICC), and the method of Bland-Altman. Results: The mean supine lnRMSSDx20 values were as follows: 89.39 ± 6.84 for the 7 days; 89.72 ± 7.00 for 5 days; 89.09 ± 7.09 for 3 days. When compared to the 7 days supine measures, the 5 and 3 days values revealed ICC values of 0.99 and 0.96, respectively, with tight limits of agreement (2.53 above to 1.87 below the mean difference of 0.33 for 5 days and 3.50 above to 4.10 below the mean difference of −0.30 for 3 days). The mean standing lnRMSSDx20 values were as follows: 70.43 ± 9.36 for 7 days; 70.65 ± 9.17 for 5 days; 70.31 ± 9.62 for 3 days. When compared to the 7 days standing measures, the 5 and 3 days values revealed ICC values of 0.98 and 0.96, respectively, with tight limits of agreement (4.25 above to 4.01 below to mean difference of 0.22 for 5 days and 5.31 above to 5.55 below the mean difference of −0.12 for 3 days). Conclusions: This study showed that lnRMSSDx20 recordings in supine and standing positions averaged over 5 and 3 days showed good agreement with the 7 days mean in female collegiate soccer players during a spring season microcycle. Future research should aim to determine if 5 and 3 days recordings reflect changes in training status over a chronic period. Practical Application: lnRMSSDx20 values averaged over a 1 week period can be used as an objective measure of training status in athletes. However, obtaining data with a daily frequency is challenging in the applied sports setting, limiting the potential usefulness of HRV as a monitoring tool among sports teams. It appears that 5 days or 3 days recordings of ultra-short-term lnRMSSDx20 obtained by athletes on their smart phone device will suitably reflect the 7 days mean. This greatly reduces compliance demands of athletes. Limiting data acquisition to 5 or 3 weekdays instead of over the entire 7 day period may enhance the practicality and convenience of HRV monitoring in field settings.

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30. Predicting Eccentric One-Repetition Maximum From Concentric One-Repetition Maximum in the Bench Press

S. Kelly,1 L. Brown,2 B. Alvar,3 and L. Black4

1Vanguard University of Southern California; 2California State University, Fullerton; 3Rocky Mountain University of Health Professions; and 4California Baptist University

Research indicates eccentric overload is beneficial for increasing muscular strength and hypertrophy, in addition to a number of health-related benefits. However, testing ECC 1RM in order to design a scientifically-based resistance training program is difficult as it requires specialized equipment or multiple trained spotters. Therefore, a tool which allows for prediction of ECC 1RM is useful in designing a training program with an eccentric emphasis. Purpose: The purpose of this study was to determine if eccentric 1-repetition maximum (ECC 1RM) could be predicted from concentric one-repetition maximum (CON 1RM) in the bench press exercise. Methods: Thirty healthy men (age = 24.63 + 5.6 years) were tested for 1RM in CON and ECC bench press. A mechanical hoist was affixed to a gantry crane and placed over a standard flat bench. The hoist was connected via chain to 45lb plates that were loaded on a standard barbell, which allowed for mechanical raising and lowering of the barbell. Following general and bench press-specific warm up, 1RMs were randomly tested 7 days apart. For CON repetitions, the weight was mechanically lowered to the chest and the participant pressed it up until the elbows were fully extended. The ECC bench press consisted of lowering a barbell from a fully extended elbow position to the chest in a continuous, smooth, controlled manner for 3 seconds as determined by a countdown in correspondence to a digital metronome. A failed ECC repetition was defined as the participant being unable to control the velocity of the descent of the bar at any time or allowing the barbell to touch the chest before the 3 second count expired. Regression analysis was used to predict ECC 1RM from CON 1RM. Results: Regression analysis revealed that CON 1RM was a highly significant predictor of ECC 1RM (b = 1.004, p < 0.001, R2 = 0.83) using the equation: y = 108.74 + 1.004 (CON 1RM) Conclusions: These data indicate that ECC 1RM can be accurately predicted from CON 1RM in the bench press exercise. Practical Application: Testing CON 1RM is a simple process which is familiar to most resistance trained individuals. Intensity of exercise is a primary variable which is manipulated as part of a resistance training program and is calculated as a percentage of 1RM for a specific exercise. Therefore, a scientifically designed program should have either a directly measured or predicted 1RM from which to calculate intensity. Predicting ECC 1RM from CON 1RM provides an efficient method for designing an eccentrically-focused resistance training program.

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31. The Effect of Intermittent Cooling on Thermoregulation, Cardiovascular Strain and Recovery in Collegiate Basketball Players

S. Bishop,1 T. Phelps,1 R. Herron,2 G. Ryan,3 and C. Katica4

1Texas A&M University–Commerce; 2The University of Alabama; 3University of Montana Western; and 4Pacific Lutheran University

Cryotherapy is commonly used in sport and performance applications however primarily as a means for improved recovery. Intermittent cooling during competition may contribute to improved performance by modifying perceptual or physiological stress. Purpose: The purpose of this study was to investigate the effects of intermittent cooling (IC) vs. no cooling (NC) through the course of a collegiate basketball game in a thermoneutral environment. Methods: Eight healthy, (age, 22 ± 1 year, height, 186.7 ± 7.1 cm, weight 93.4 ± 10.1 kg) competitively-trained collegiate basketball players participated in a randomized and counterbalanced repeated measures protocol. Participants performed in 3 simulated games. Each trial was separated by a 24 hours recovery period to best simulate tournament-style play. Measurements of heart rate (HR), core temperature (Tc), rating of perceived recovery (RPR), and rating of perceived exertion (RPE) were recorded every 4 minutes in a thermoneutral environment (20.9 ± 0.7 C°). Data was collected every4 minutes to simulate the current NCAA collegiate basketball game play. Tc data were analyzed using a 2-way repeated measures analysis of variance (ANOVA, treatment x time) to test the significance of mean differences after each 4 minutes interval. As non-parametric data, frequency distributions were analyzed for subjective measures (PRS, RPE). Both subjective measures were re-coded and evaluated by a related-samples Wilcoxon signed-rank test. Results: The results demonstrated that cooling decreased HR during IC when compared to NC but were not significantly different (IC = 124 ± 38, NC = 126 ± 38, p = 0.26), Tc (IC = 38.1 ± 0.5, NC = 38.2 ± 0.6, p = 0.23). RPE was not found to be significantly different, but RPR significantly improved with IC when compared to NC. Practical Application: Though intermittent cooling did not significantly attenuate a rise in core temperature or working heart rate, results suggest cooling could aid subjective recovery during collegiate basketball performance in a thermoneutral environment.

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32. Evaluating the Agreement Between Ultra-Short-Term Heart Rate Variability Indexes and Accepted Recommendations in Collegiate Athletes

M. Esco and A. Flatt

Auburn University at Montgomery

Purpose: The purpose of this study was to evaluate the agreement of the vagal-related heart rate variability index (HRV) log-transformed root mean square of successive R-R intervals (lnRMSSD) measured under ultra-short-term conditions (<60 seconds) with conventional longer term recordings of 5-minutes in collegiate athletes under resting and post-exercise conditions. Methods: Five-minute electrocardiographic recordings were performed at rest and at 25–30 minutes of supine recovery following a maximal exercise test in 23 male athletes (age = 21.3 ± 2.1 years, height = 185.9 ± 5.7 cm, weight = 82.5 ± 8.3 kg,

= 51.4 ± 4.7 ml·kg−1·min−1). From each 5-minute segment, lnRMSSD was determined and recorded as the criterion measure. Within each 5-minute segment, lnRMSSD was also determined from randomly selected ultra-short-term segments of 10 seconds, 30 seconds, and 60 seconds in length. Agreement was determined with intraclass correlations (ICC) and the method of Bland-Altman. Results: When compared to the criterion measures, the ICCs decreased (from 0.98 to 0.81, p ≤ 0.05) and limits of agreement increased (±1.98 SD of the mean differences from 0.22 to 0.94), respectively, as ultra-short-term measurement duration decreased (i.e., from 60 seconds to 10 seconds). Conclusions: The results of this study suggest good agreement between ultra-short-term lnRMSSD and criterion 5-minute measures. However, as measurement duration decreased from 60 seconds to 10 seconds, the agreement to the criterion lnRMSSD measures also decreased. Therefore, 60 seconds values appeared to provide the best agreement with the criterion measures. Practical Application: It is likely that shorter HRV measurement durations may increase the potential use of HRV in field settings. Until the current study it was unclear whether lnRMSSD measured within 60 seconds or less would provide acceptable measures of agreement with recordings that followed the recommended time requirements in athletes. We found good relationships between the ultra-short-term and criterion measures. However, it should be noted that the 60 seconds segments provided the strongest correlation and tightest limits of agreement in the resting and exercise recovery conditions. Due to these results, the utility of ultra-short-term lnRMSSD measures, especially 60 seconds in duration, within field settings for monitoring athletes at rest and in response to stress appears promising.

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33. Body Weight Adjusted Hip Strength Ratios in the Weight Training Population

W. Hanney,1 M. Kolber,2 W. Carroll,1 R. Heilman,1 P. Salamh,3 C. Rothschild,1 and P. Pabian1

1University of Central FL; 2Nova Southeastern University; and 3SEO Physical Therapy

Purpose: Hip strength Imbalances have been implicated in multiple orthopedic conditions. However, to date, normative values for the weight training population has not been reported. Therefore, the objective of this study was to provide normative strength ratios between agonist/antagonist muscle groups adjusted for body weight in the weight training population. Methods: Two hundred (200) adults (N = 200; 139 men, 61 females) mean age 27.2 years ± 9.3 were recruited that participated in weight training 3 times per week for at least 1 year (women 27.2 years ± 9.9; height 163.9 cm ± 6.6; mass 72.6 kgs ±10.1) (men 27.0years ± 9.1; height 179.6 cm ± 6.9; mass 99.1 kgs ± 14.4). Hip strength was measured in Newtons (N) for 6 planes of motion using a hand held dynamometer and body weight adjusted strength ratios calculated for hip internal rotation (IR)/external rotation (ER), extension/flexion, adduction/abduction, abduction/ER and adduction/IR. Each hip was evaluated which provided strength ratio data for 400 hips overall (278 male hips and 122 female hips). Strength assessments used procedures with reported Intraclass Correlation Coefficients (ICCs) of 0.9 or greater Results: Body weight adjusted strength ratio for IR/ER in the entire population was 0.92 (men 0.97, women 1.04) extension/flexion 0.98 (men 0.96; women 1.03) adduction/abduction 1.02 (men 1.03; women 0.99) abduction/ER 0.93 (men 0.90; women 0.99) adduction/IR 1.04 (men 1.07; women 0.97) IR/ER, Extension/Flexion, Abduction/ER were higher in females while men demonstrated greater ratios for hip adduction/abduction and adduction/IR. Conclusions: Reported body-weight adjusted strength ratios may be used as a reference and help guide practice when determining return to play, screening for illness, and injury prevention. The results of the current study suggest weight training males demonstrated slightly greater strength of the hip external rotators when compared to the internal rotators, greater hip flexion strength when compared to hip extension as well as greater hip external rotators when compared to abduction. These values were reversed in women. However, in both men and women hip strength ratios for adduction and abduction were close to 1. Practical Application: Based on current study body weight adjusted strength ratios for hip strength approached 1 which suggests relative balance of agonist and antagonist muscle groups of the hip are present in the weight training population. Minor differences existed between men and women and should be considered when evaluating hip strength ratios in weight training individuals.

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34. The Influence of Energy Shots on Power and Velocity of a Simulated Forehand Stroke Utilizing Medial Rotation of the Shoulder

B. Jacobson,1 E. Conchola,1 J. Sellers,1 and K. Williams2

1Oklahoma State University; and 2Okalhoma State University

Energy shots (ESs) are a fast growing segment of a multimillion dollar energy drink market. Promotional efforts utilizing sports stars claim greater vitality, energy, and better performance. Purpose: The purpose of this study was to assess the effect of ESs on power and velocity in a simulated forehand stroke utilizing medial shoulder rotation. Methods: Following IRB approval 23 college-age volunteers (males = 11, females = 9) (weight 76.91 + 15.86 kg, height 174.15 + 8.60 cm) were randomly divided into a control group and an experimental group. Prior to testing, all subjects were familiarized with the assigned task. On the day of testing subjects reported to the lab at least 6 hours post-prandial and 48 hours caffeine free. Pre-tests included 3 medial, maximal shoulder rotations at the prompt of a visual stimulus while average power and velocity was recorded. Following the pre-test the subjects were given a 57 ml shot of either an ES or a similarly colored and tasting placebo on a double blind format. Following a 30 minutes absorption period, subjects were again tested. Results: While the treatment group outperformed the placebo group in both power and velocity measures, 1-way ANOVAs yielded no significant differences in either power (p = 0.07) or velocity (p = 0.06). Conclusions: The current study found slight improvement in both power and velocity in the treatment group while a slight decline in performance was noted for the placebo group. It is possible that a larger separation in results could occur with a higher dose. A limitation of this study was the small number of participants. It is recommended that further studies utilize a larger sample. Practical Application: Currently there is no evidence to support the use of ESs to enhance physical performance as reflected in a gross motor skill.

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35. Demographics, Training and Injury History of Individuals Competing in Obstacle Race Events

A. Jagim,1 J. Repshas,2 and J. Oliver2

1Gannon University; and 2Texas Christian University

Introduction: As the popularity of obstacle-race events such as The Warrior Dash, Tough Mudder, and Spartan Race increase, a basic understanding of the athletes participating in these events is needed. Further, due to a high risk of injury associated with such events, a characterization of the most common types of injuries may assist in developing training and/or changes in competition to reduce injury. Purpose: Therefore, the purpose of this study was to gain knowledge about the specific physiological characteristics and training history associated with participants of obstacle race events. Further, we also sought to obtain the incidence of injury in said participants. Methods: One hundred twenty-two athletes (males, n = 75; females, n = 47) (30.8 ± 9.3 years, 172.5 ± 17.5 cm, 76.4 ± 13.9 lbs) were identified via social media outlets, mass emails and word of mouth. The participants completed a voluntary online survey (Qualtrics) answering questions regarding their background, training habits, and injury history. Results: 82% reported competing in high school athletics, while only 25% reported competing at the collegiate level. Average number of races participated in was 3.3 ± 3.7 with Tough Mudder being the most popular (45%) followed by Spartan Race (41%). 97% reported finishing the race(s). Only 77% of the participants reported a desire to complete another race. 83% of participants reported completing some sort of training prior to the race with the majority of training modes consisting of weight lifting (68%), interval training (67%), and long-distance training (67%). Forty-one percent of participants reported training for less than 3 months while 32% trained for 3–6 months prior to the event. Sixteen percent of the participants followed a structured training program prescribed by a fitness professional training an average of 5.25 ± 1.2 days per week while 78% did not. Those reporting training reported 4.8 ± 3.6 hours of resistance training, 6.0 ± 11.9 hours of slow-steady state endurance training, and 2.5 ± 2.6 hours of high-intensity interval training during their most intense training week. This corresponded to 15.5 ± 13.1 miles of running, 4.6 ± 7.2 miles of trail running and 11.7 ± 35.5 miles of biking. Twenty-five percent of the participants reported suffering an injury during a race and 3% reported being injured on more than 1 occasion. 30% of the injuries were not related to previous injuries. The most common injuries were overuse injuries (11%), muscle strains (9%) and sprains (8%). The most common injury areas were of the lower body particularly the knee and ankle. Conclusions: The majority of people competing in obstacle-race events appear to have an athletic background and participate in some form of training prior to the race. However the majority of people who trained did so for less than 3 months. The injury rate appears to be high as 25% of the participants reported suffering an injury during a race with the most common injuries being to the knee and ankle, suffered during the running portion of the race. Practical Application: Due to the unique and unpredictable demands of these types of races it is difficult to recommend a specific training program. However, due to the high incidence of injury perhaps a longer training period with a focus on strengthening the stabilizing muscles of the lower extremities with an emphasis on improving balance would help lower the incidence of injury.

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36. Reliability and Comparisons of Handgrip Strength, Leg Extensions Muscle Function, and Balance in Older Men

N. Jenkins,1 S. Buckner,1 J. Goldsmith,1 K. Cochrane,1 H. Bergstrom,2 R. Schmidt,1 G. Johnson,1 T. Housh,1 and J. Cramer1

1University of Nebraska–Lincoln; and 2University of Nebraska

Purpose: To quantify the test-retest reliability and relationships among isometric handgrip strength (HGMVC) and rate of force development (HGRFD), isometric leg extension peak torque (LEMVC) and rate of torque development (LERTD), isokinetic peak torque (PT) and mean power (MP) at 60°·s−1 and 180°·s−1, and balance (Functional Reach). Methods: Sixteen older men (mean ± SD; age = 72.1 ± 7.1 years; height = 178.4 ± 6.1 cm; mass = 81.7 ± 13.2 kg) performed 3 maximal voluntary isometric hand-grip muscle actions, 3 isometric leg extension muscle actions, 3 isokinetic leg extension muscle actions at 60°·s−1 and 180°·s−1, and a functional reach test to assess balance during 2 separate visits separated by 48–72 hours. Intraclass correlation coefficients (ICCs), confidence intervals (95% CI) about the ICCs, and standard errors of measurement (SEM) were calculated for each dependent variable to quantify test-retest reliability. The SEM was also expressed as a percentage of the grand mean (coefficient of variation, CV) so that it could be compared across variables. Pearson product-moment correlation coefficients were calculated to examine the relationships among the dependent variables during visit 2. Results: Table 1 contains means, standard deviations, ICCs, 95% CIs, SEMs, and CVs for each of the dependent variables. The ICCs and CVs for HGMVC, LEMVC, PT 60°·s−1, PT 180°·s−1, MP 60°·s−1, MP 180°·s−1, and Functional Reach were 0.78–0.93 and 5.35–16.10%, respectively. However, the ICC for LERTD was 0.44 and was not different from 0 (p ≤ 0.05). The ICC and CV for HGRFD were 0.67 and 42.80%, respectively. HGMVC was not related to LEMVC, PT 60°·s−11, PT 180°·s−1, MP 60°·s−1, MP 180°·s−1, or Functional Reach (r = 0.14–0.47; p > 0.05). However, moderate to strong relationships were found among PT 60°·s−1, PT 180°·s−1, MP 60°·s−1, MP 180°·s−1, and Functional Reach (r = 0.51–0.95; p ≤ 0.05). Conclusions: HGMVC, LEMVC, PT 60°·s−1, PT 180°·s−1, MP 60°·s−1, MP 180°·s−1, and Functional Reach were reliable, while HGRFD and LERTD were not. Furthermore, HGMVC was not related to LEMVC, PT 60°·s−1, PT 180°·s−1, MP 60°·s−1, MP 180°·s−1, or Functional Reach. Conversely, there were strong relationships among PT 60°·s−1, PT 180°·s−1, MP 60°·s−1, MP 180°·s−1, and Functional Reach. Practical Application: LERTD and HGRFD were unreliable and should not be used to assess changes in muscle function for older men. Additionally, HGMVC is commonly used as a surrogate for functionality and mobility in older adults and is used to classify sarcopenia in clinical practice. However, HGMVC was unrelated to leg extensor strength and balance in this sample of older men. Therefore, HGMVC may not predict balance, but may compliment dynamic, lower limb isokinetic strength assessments, which may be more relevant to balance and risk of falls.

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37. Relationships Between Stress and Performance Improvement for Females Following 15 Weeks of Weight Training

M. Lane,1 E. Moore,2 R. Kudrna,3 M. Fry,1 and A. Fry1

1University of Kansas; 2University of North TX; and 3DeSales University

Introduction: This study builds off previous research showing that the greater the number of stressful life events experienced by college students, the smaller their strength gains in a semester-long weight training class. Specific research examining the relationship between training and stress for females is limited. This data is part of a larger study conducted to expand upon Bartholomew, Stults-Kolehmainen, Elrod, and Todd's 2008 findings. Purpose: To examine the relationship between undergraduate female students' reported stress and physical performance improvement following a semester-long weight training class. Methods: Forty-eight undergraduate female students (X ± SD; age = 21.7 ± 5.0 years, height = 1.63 ± 0.07 m, weight = 61.2 ± 8.7 kg) enrolled in a midwestern university's weight training classes completed the following physical performance tests: body composition (bioelectrical impedance), 4 RM squat, 4 RM bench press, and Chester Step Test. The class met for 2, 50 minutes circuit training sessions a week for 15-weeks. The participants also completed the 11 item Stress and Tension Test (Farquhar, 1987) on a 4 point response scale (0 = rarely to 3 = always) that are summed for a total general stress score. Participants also completed the Personal Stress Tests (Medicine Shoppe International, Inc., 1985) to assess how stressful different elements of their life are; particularly, the participants' perception of their physical condition and their weight control/image. Each subscale has 4 items, with a 5-point response scale (1 = almost never to 5 = almost always), that are summed for a total score. The circuit training was periodized to undulate each week through strength, hypertrophy, and endurance. The pre- and post-data for the 3 psychological measures and 4 physical performance assessments were tested for significance. Results: Paired samples t-test results indicated significant pre-post improvement in their squat (t34 = −8.37, p < 0.001), bench press (t33 = −8.11, p < 0.001), and step-test performance (t35 = −2.33, p = 0.026); plus, their stress due to their physical condition (t34 = 3.23, p = 0.003) significantly decreased. On average, the participants' increased their squat by 12.5 kg, bench press by 6.3 kg, and step test by 4:00 minutes. The participants' stress due to their physical condition decreased 0.29 points. There were 2 significant correlations between the participants' physical performance and reported stress. Pre-stress and tension were significantly correlated (r = −0.45, p = 0.007) with post-squat performance. Their pre-step test performance was significantly correlated (r = 0.42, p = 0.008) with their pre-level of stress due to their physical condition. Conclusions: This study's finding that the greater the individuals' stress, the less their physical performance improvement aligned with Bartholomew, et al.'s (2008) findings. In addition, this study also illustrated the psychological benefits female students' gain from completing a semester-long weight training class. Specifically, their physical condition was significantly less of a stressor by the end of the semester-long weight training class. Practical Application: In addition to being able to identify individuals at risk for diminished performance gains related to trainees' life stress, coaches may also be able to show gains in terms of their trainees' improved physical performance and reduced physical condition-related stress.

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38. The Effects of Preventative Ankle Taping on Planned and Reactive Agility and Peak Ankle Muscle Activity in Basketballers

R. Lockie,1 M. Jeffriess,2 T. McGann,1 S. Callaghan,3 and A. Schultz1

1University of Newcastle/Exercise and Sport Science; 2University of Technology, Sydney; and 3Edith Cowan University

Taping can reduce ankle sprain incidence by providing joint support, and potentially compensating muscle function. However, there are conflicting findings regarding taping effects on planned and reactive agility. This is an issue, as athletes may not use preventative taping if it hinders athletic performance. Purpose: To determine the effects of preventative ankle taping on planned and reactive agility performance and peak activation of ankle muscles in basketballers. Methods: Twenty male basketballers, with no ankle pathologies, attended 2 testing sessions. During these sessions, subjects completed 6 planned and 6 reactive randomized trials (3 left and 3 right for each condition) of the Y-shaped agility test (Figure 1). In 1 session, subjects had both ankles un-taped. In the other, subjects had both ankles taped using a modified subtalar sling method. Electromyography measured activity of selected ankle dynamic stabilizers (tibialis anterior [TA], peroneus longus [PL], peroneus brevis [PB], soleus [SOL]) for both the inside and outside cut legs during the change-of-direction step (first step past the trigger gate that initiated the cut). The outside cut leg was the leg furthest from the target gate; the inside cut leg was the leg closest to the gate. Data was normalized against 10-meter sprint muscle activity. Paired samples t-tests determined any significant (p ≤ 0.05) differences in agility times and muscle activation between un-taped and taped conditions. Results: There were no differences in planned or reactive agility times between the un-taped and taped conditions (p = 0.223–0.982). The peak normalized PL activity for the inside cut leg decreased when taped for the planned left (p = 0.007), reactive left (p = 0.026), and reactive right (p = 0.007) cuts. The peak normalized outside leg SOL activity increased during the taped planned left cut (p = 0.022). There were no other changes to SOL activity, or to the TA or PB, during the cut with taping. Conclusions: The modified subtalar sling taping method did not affect agility. This taping method potentially reduced the need for inside leg PL activity as it followed the line of muscle action to aid foot eversion. This may reduce the kinetic demand for the PL during certain cuts. The increased SOL activity was perhaps due to the taping method restricting rear-foot sagittal plane motion, potentially allowing the SOL to aid in force attenuation. The modified subtalar sling will not negatively affect agility or typical ankle muscle function in basketballers. Practical Application: Athletic trainers and strength coaches can use the modified subtalar sling as a preventative taping method on their athletes without adversely affecting agility. Taping will generally not affect peak ankle muscle activity, but peak PL activity may be reduced. This could provide an additional reserve of muscle activation if it is required. Acknowledgments: The study received financial assistance from the NSW Sporting Injuries Committee.

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39. Comparison of Techniques for Estimating %FAT in NCAA Division II Women Athletes

J. Mayhew, L. Jorn, D. Fuemmeler, J. Hill, K. Maakestad, and J. Arabas

Truman State University

Dual-energy x-ray absorptiometry (DXA) appears to have become the new standard by which body composition is being evaluated. Limited information is currently available on the agreement of other prediction techniques and DXA in female athletic populations. Purpose: To compare selected skinfold prediction equations and bioelectric impedance analysis (BIA) to DXA %fat in NCAA Division II women athletes. Methods: Fifty-four NCAA Division II women athletes (Mean ± SD: age = 20.3 ± 1.0 years, height = 169.9 ± 7.6 cm, weight = 75.4 ± 12.0 kg, BMI = 25.0 ± 3.9 kg/m2) from 4 sports were assessed during the off-season for 8 skinfolds (SKF): biceps, triceps, subscupula, suprailium, abdomen, thigh, knee, and calf. Six SKF equations previously developed to estimate %fat in athletes were evaluated. Single-frequency (50 Hz) hand-to-hand BIA (H-BIA) and foot-to-foot BIA (F-BIA) devices with athletic settings were also assessed. DXA was used as the criterion of %fat. Results: All predicted %fat techniques significantly underestimated DXA %fat (29.9 ± 6.0%) by −1.7 to −11.8 %fat units. BIA devices significantly underestimated DXA %fat despite high correlations with the criterion (ICC = 0.731–0.911). Of the SKF equations, the Durnin-Wormsley equation produced the closest estimate to DXA %fat (28.2 ± 3.7%, ICC = 0.876, CV = 10.0%). However, the Durnin-Wormsley equation tended to overestimate %fat values 25% compared to DXA. H-BIA (24.5 ± 6.3%, ICC = 0.895) and L-BIA (25.4 ± 6.3%, ICC = 0.894) devices produced estimates that were significantly lower than DXA but were not significantly different from each other. Conclusions: The prediction techniques currently available to estimate %fat in Division II female athletes appear to significantly underestimate values derived from DXA. Prediction error typically increased at greater %fat and body mass values. Practical Application: If DXA is to be accepted as the criterion for assessing body composition in women, new prediction equations may need to be developed. Higher %fat values than previously noted in the literature may also need to become the new normal standard for college women athletes when using DXA as the criterion.

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40. Comparison of Functional Fitness Measures Among Community-Dwelling Older Adults

S. Paulson,1 M. Gray,2 and D. Lentz3

1Shippensburg University; and 2University of Arkansas, 3Results Therapy & Fitness

Purpose: The purpose of this study was to compare low and high functionally fit older adults on selected functional fitness assessments. Methods: Fifty-six older adults volunteered to complete the following FF tests: power stair climb (PSC), habitual 20 m walk (HW), 30-second chair stand (CS), and 8-foot up-and-go (UPGO). All participants were free from uncontrolled cardiovascular, metabolic, and pulmonary disease. Relative power from the PSC was used to create the 2 power groups: low (n = 32, age: 74.3 ± 6.0 years; height: 163.6 ± 10.5 cm; mass: 73.6 ± 12.4 kg) and high (n = 24, age: 71.7 ± 5.2 years; height: 164.8 ± 10.7 cm; mass: 73.2 ± 13.3 kg). For the PSC, each subject was instructed to ascend a set of 9 steps as quickly and as safely as possible for 3 trials. The best time was used for analysis. Data were analyzed using a 1-way ANOVA. Results: The 1-way ANOVA yielded a statistically significant difference between the groups on HW speed (p < 0.01), CS (p < 0.01), and UPGO (p < 0.001).Conclusions: Community-dwelling older adults with greater relative power walked faster (13%), performed more CS (21%), and completed the UPGO quicker (29%) than the low power group. Practical Application: As one ages muscular power decreases which increases fall risk and functional fitness declines. Muscular power is imperative to the ability to perform everyday activities as well as maintaining independence. The results of this study showed that older adults with greater power walked faster and out performed the lower power group on selected measures of functional fitness.

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41. Deceptive Load Information Enhances Lat Pulldown Strength

T. Piper,1 J. Schnaiter,2 and J. Grau3

1Western Illinois University, Department of Kinesiology, Major of Exercise Science; and 2Ball State University, 3Western Illinois University

One potential limitation to maximal strength testing is that participants may perform only up to the level of their expected maximum performance, based upon prior experience. Eliciting maximal strength may be altered by offering load information which makes a person believe they are lifting less than the actual load on the barbell. Purpose: The purpose of this study was to determine the effects of deceptive load information on maximal strength during a lat pulldown exercise. Methods: Thirty-two male college students (mean ± SD age, 19.87 ± 1.62 years) performed 5 testing sessions, each separated by a minimum of 48 hours. To mask the true deceptive nature of the study the weight stack of the machine was concealed and participants were informed that the concealment was to ensure focus on proper technique during tests. One orientation trial day was completed, followed by the establishment of the 1-repetition maximum (1RM) control test session (C) in which participant's received accurate load information. During the 3 subsequent 1RM randomized sham testing sessions, participants received deceptive load information in which reported loads were 5, 10, and 15% (L-5, L-10, L-15 respectively) below the actual load selected on the weight stack. This deception resulted in the subjects lifting loads which were 5, 10, or 15% above what they were told. On the final test day (FT) participants were informed that the loads reported to them during the prior 3 sessions were mistakenly reported inaccurately. Participants were then given accurate load information for the final 1RM trials. No verbal encouragement was given during any of the trials other than the reporting of reported weights being attempted. After all of the participants completed all testing sessions, they were debriefed and the true nature of this research, the deception and their true 1RM scores were disclosed. Repeated Measures ANOVA with Bonferroni adjusted pairwise comparison was used to evaluate differences in 1RM scores (p ≤ 0.05). Results: The 1RM measures produced the following results: (mean ± SD; C = 162.19 ± 5.17 lbs; L-5 = 167.50 ± 5.00 lbs; L-10 = 167.81 ± 5.27 lbs; L-15 = 167.19 ± 4.92 lbs; FT = 170.00 ± 4.98). Significant differences were revealed between C vs. L-5, C vs. L-10, and C vs. FT. Conclusions: While a training effect may account for the significantly higher scores on FT, deceptive load information of 5 and 10% were shown to be effective at increasing 1RM measures on the lat pulldown. Practical Application: When attempting to measure a 1 RM lift it may be advantageous to use deceptive load information of up to 10% of previously established measures. In doing so the lifter who is striving to reach their perceived 1 RM levels actually produce higher strength outputs than they might believe possible, and thus establishing a new personal record attempt. Deception may be a powerful psychological intervention for enhancing maximal strength performance for the lat pulldown exercise.

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42. Hamstring Activation of Two Different Recovery Positions in the Power Clean Exercise

C. Proulx,1 M. Stone,2 J. Roethlingshoefer,3 and D. Laing4

1New York Chiropractic College; 2East Tennessee State University; and 3University of Louisville, 4Westfield State University

Introduction: Training, or physical conditioning, has been instituted for many years and utilized for performance enhancement and injury reduction for competitive and recreational sport. However, research has been more supportive in assessing conditioning as performance enhancement through outcomes measures, as well as coaching. The benefits of resistance training in injury reduction have a far less evaluated relationship with regards to specific technique in training exercises. Purpose: To evaluate the effect of landing performance on activation of the biceps femoris muscle during the power clean, while maintaining constant performance during the concentric phase. Methods: The study was a single trial within subject design. The study took place in the clinical laboratory at a University. Subjects (n = 9) were male intercollegiate athletes at the University who were all familiar with and train with the power clean exercise >1 year. All subjects conducted a warm up of the exercise prior to executing 3 repetitions each of a power clean exercise with the catch in the completely upright position (UP) and in the squat clean position (SQ). Main outcome measures included surface electromyography of the left biceps femoris muscle for comparative analysis in P-P and MAX muscle activity and force plate peak force measures to ensure consistent performance outcome of the exercise. Results: Both maximum and P-P were statistically higher in the half squat position, p = 0.03(r = 0.92) and p = 0.02 (r = 0.93), respectively. There was no statistical significant difference in peak vertical force in either exercise situation, p = 0.55 (r = 0.82). Conclusion and Practical Application: Both situations provided the same force production, one of the outcome measures of the exercise. Hamstring activation was significantly higher in the squat catch position, indicating recovery of the exercise may have implication to considering the carry over effect to recovery during sport, such as deceleration in running and agility. Hamstring activity is implicated in reducing non-contact knee injuries. Coaches and athletes may be able to apply this information when considering the injury prevention aspect of a particular exercise. Technique may play an important in the injury prevention component of strength and conditioning and not just performance enhancement.

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43. Electromyographic Activity of the Core Musculature During Planks Performed With and Without Instability Devices

R. Snarr1 and M. Esco2

1Arizona State University; and 2Auburn University at Montgomery

Recent fitness trends have been geared towards incorporating instability methods such as Physio-Balls (PB) and Suspension Devices (SD). The purported advantage of these modalities is the increased muscular demand due to decreased stabilization. Limited research is available to determine the neuromuscular recruitment patterns of selected core muscles while performing an abdominal plank with the use of instability devices. Purpose: The purpose of this investigation was to compare the electromyographical (EMG) activity of the rectus abdominis (RA), external oblique (EO), and lumbo-sacral erector spinae (LSES) during planks performed on a stable surface (REG), with a PB, and with an SD. Methods: Apparently healthy men (n = 6, age = 23.92 ± 3.64 years) and women (n = 6, age = 22.57 ± 1.87 years) volunteered to participate in this study. All participants performed 3 variations of the traditional plank. For each, the feet were securely placed on the ground, while the forearms were either placed on a stable surface (i.e., REG), on a PB, or on an ST. Each exercise was performed isometrically for 5 seconds. For this study, the order of the exercises was randomized to prevent fatigue error during data collection. Mean peak (raw) and normalized (%MVC) EMG values were recorded for each muscle group during each 5 second isometric exercise. Results: Results are shown in Table 1. For the RA, the SD elicited a significantly greater raw and %MVC muscular activity as compared to the REG and PB. The REG showed a significantly lower RA activation (raw and %MVC) (p ≤ 0.05) compared to either of the instability devices. In terms of the EO, the SD showed a significantly greater (p ≤ 0.05) raw EMG activation than either the PB or the REG. The REG showed significantly lower EO active (p ≤ 0.05) compared to the PB and SD. The PB and SD showed no significant differences in LSES. However, planks performed on both devices yielded significantly higher LSES EMG values compared to REG (p ≤ 0.05). Conclusions: This study found significantly greater EMG activity in the RA, EO, and LSES when planks were performed with a Physio-Ball or a Suspension Device compared to the traditional method. However, results also indicated that when planks are performed with the elbows on the suspension device the EMG activity of the RA (raw and %MVC) and EO (raw) was greater compared to when the elbows were placed on a physio-ball. Practical Application: Practitioners should take note that traditional planks are an important exercise to target the RA, EO, and LSES. Instability devices, such as a physio-ball or suspension device appears to offer advanced progressions of the plank and may be desirable for those wanting an increased challenge of the core musculature.

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44. The Relationship Between Visual Skills and Reactive Agility of NCAA Division I Male Basketball Players

F. Spaniol and J. Powell

Texas A&M University–Corpus Christi

Purpose: The purpose of this study was to investigate the relationship between visual skills and reactive agility of NCAA Division I Male Basketball Players. Methods: Thirteen NCAA Division I basketball players, (age 20.15 ± 1.34 years, height 190.93 ± 12.00, weight 87.06 kg ± 9.46 kg, LBM 80.03 kg ± 9.35 kg) participated in this study. Performance data was collected at Texas A&M University–Corpus Christi during 1 session in the biomechanics laboratory. Performance data included; visual alignment (VA), visual depth perception (VDP), visual flexibility (VF), visual recognition (VR), visual tracking (VT), and an overall composite visual score (CVS) measured by Vizual Edge Performance Trainer. Furthermore, Dynavision D2 Light Board was used to measure the average (D2A), slowest (D2S), fastest (D2F), and median (D2M) reaction time taken to hit a light sensor, and the total amount of light sensors hit (TSH). Additionally, iSPAN Dynamic Trainer was used to measure the average (AT), slowest (ST), and fastest (FT) time to turn off a light sensor as well as an overall time to complete the test (OT) and distance (DT) from the ISPAN Dynamic Trainer. Means and standard deviations were calculated for each performance variable. All Vizual Edge Performance Trainer variables were analyzed by Pearson correlation coefficient (r) against iSPAN Dynamic Trainer and Dynavision D2 Light Board scores. The alpha level was set at p ≤ 0.05. Results: Statistical significance was found with the relationship between OT and VT percentage correct (r = −0.57), VR time and AT (r = 0.58), VR time and D2S (r = 0.56), respectively. Conclusions: The results show that VT percentage specifically, as well as VR time is significantly correlated with OT to complete the iSPAN Dynamic Trainer protocol. Practical Application: Data from this study can serve to inform players and coaches of the importance that visual skills play in both the dynamic visual skills and the reactive agility of an athlete. In addition these findings can contribute to the issue of inclusion of visual skills training as part of an athletic strength training program.

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45. Supplemental GAKIC Enhances Lower-Body Resistance Training Performance in Trained Males During a Hypertropy Protocol

B. Wax,1 E. Hall,1 A. Kavazis,2 A. Walton,1 M. Cook,1 B. Vickers,1 J. Townsend,1 and K. Gilliland3

1Mississippi State University; 2Auburn University; and 3Mississippi State University

Glycine-arginine-α-ketoisocaproic acid (GAKIC) has been reported to enhance resistance performance during muscular strength and endurance protocols. Purpose: The aim of this study was to investigate the potential ergogenic effects of GAKIC ingestion during repeated bouts of lower-body resistance exercise during a hypertrophy protocol. Methods: Eleven resistance trained males (age = 22.7 ± 1.7 years, mass = 95.1 ± 16.2 kg, height = 1.77 ± 0.09 m) participated in a randomized, counterbalanced, double blind study. Participants were randomly assigned to placebo or GAKIC (10.2 g) and performed 5 sets each of 67% of 1-repetition maximum leg press, hack squat, and leg extension to failure. Subjects were allotted 90 seconds rest periods between sets. Total load volume was calculated by multiplying the 67% of 1-repetition maximum mass lifted by the sum of repetitions to failure. One week later, participants ingested the other supplement (placebo; GAKIC) and the same exercise protocol was performed (i.e., crossover). Blood lactate and glucose, and heart rate were determined pre- and immediately post-exercise. Results: GAKIC supplementation significantly increased leg press repetitions (GAKIC = 74.8 ± 18.8; placebo = 63.3 ± 10.7, p ≤ 0.05), hack squat repetitions (GAKIC = 39.5 ± 14.0; placebo = 32.9 ± 14.8, p ≤ 0.05), and total load volume (GAKIC = 23,315 ± 7678 kg; placebo = 19,747 ± 5673 kg, p ≤ 0.05); however there was no significant difference in leg extension repetitions (GAKIC = 25.9 ± 19.1; placebo = 26.6 ± 26.2, p > 0.05). Heart rate and blood lactate were significantly increased (p ≤ 0.05) post-exercise compared to pre-exercise, but were not significantly different between GAKIC and placebo. Blood glucose was significantly decreased (p ≤ 0.05) post-exercise compared to pre-exercise, but was not significantly different between GAKIC and placebo. Conclusions: These novel findings suggest that GAKIC increases total work performed during repeated bouts of lower-body resistance exercise. Practical Implications: Our data suggests that GAKIC ingestion prior to a lower-body resistance training protocol may increase the repetitions and training volume of trained males during a hypertrophy protocol.

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46. Reliability and Precision of Anthropometric Measures of the Feet that Influence Moment Arm Length of Reaction Forces

L. Weiss,1 J. Caia,2 J. Harry,2 L. Chiu,3 B. Schilling,2 and M. Paquette2

1The University of Memphis; 2University of Memphis; and 3University of Alberta

Anthropometric dimensions of the foot influence moment arm lengths that reaction forces act through. These dimensions impact the moment of force that must be resisted by the concentrically-contracting triceps surae muscles during foot plantar flexion. Surface landmarks may be used in measuring these dimensions, but it is unclear if they are sufficiently reliable and precise to be of practical use. Purpose: To determine the stability reliability and precision of anthropometric foot dimensions based on surface landmarks. Methods: Fifteen men with experience in plyometric jump training were recruited for the study. Anthropometric dimensions of interest were the anterior-posterior distance between the posterior aspect of the calcaneus and the: (a) talocrural and (b) metatarsophalangeal joints. Measures were obtained on both the medial and lateral sides of the feet and were averaged in order to estimate a single value for each moment arm. Landmarks were palpated and marked as follows: posterior calcaneus at the distal-most point of the calcaneal tendon, most prominent aspect of both the medial and lateral malleoli, most prominent lateral-plane aspect of the distal ends of the first and fifth metatarsals. Bilateral measurements were then performed using a digital sliding caliper oriented parallel to the floor by means of a spirit level with the calcaneal landmark serving as the anchor point. Measures were obtained with subjects in 3 different conditions: non-weight bearing, bilateral weight bearing, and unilateral weight bearing as changes in the longitudinal arches would be expected to affect longitudinal dimensions distal to the talocrural joint. Measures were obtained in rested subjects on 2 occasions separated by either 24 or 48 hours. Stability reliability was determined using intraclass correlation, 2-way random model (ICC). Precision or minimum-detectable real difference was determined via 95% limits of agreement (LOA95%). Results: With 1 exception, stability reliability was high. The minimal detectable difference for the calcaneus-to-metatarsophalangeal-joint length was no more than 2.5% of the average, and for the calcaneus-to-talocrural joint length was no more than 13.4% of the average (Table 1). Conclusions: It appears that surface landmarks and a digital caliper can be used to reliably measure each anthropometric dimension in question. Practical Application: Although this was a preliminary investigation utilizing a small sample size, the findings indicate that meticulous adherence to the protocols used herein may result in the acquisition of reasonable measures of the 2 moment arms of interest. However, the shorter of the 2 roughly corresponding to calcaneal length may be more difficult to obtain. Normalizing the values for height may expand the utility of the measures.

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47. Assessment of the Flexibility of the Pectoralis Minor Muscle

D. Witt, L. Mulligan, N. Talbott, A. Higgins, and M. Duffy

University of Cincinnati

Purpose: Flexibility of the pectoralis minor (PM) is an important component of upper extremity conditioning programs. If tightness in the PM is present, shoulder dynamics can be altered resulting in a change in throwing biomechanics as well as an overall change in shoulder function. Over conditioning of the anterior shoulder muscles and the biceps without attention to the length of the same muscles can also result in a decrease in the size of the subacromial space with the potential for impingement, particularly in the overhead athlete. To monitor the length of the PM, several assessments have been suggested. Perhaps most commonly, the measurement of the length of the PM is recorded by measuring the distance from the surface an individual is lying on to the posterior aspect of the acromion. Such a measurement can be made with the elbow flexed or elbow extended. In addition, research has supported a measurement from the coracoid process to the fourth rib. The purpose of this study is to determine the reliability of these 3 common methods for measuring PM flexibility. Methods: A total of 38 shoulders from 19 subjects were measured. Subjects were selected from a population of convenience and all subjects signed an informed consent form. With a subject in hook-lying and the elbow extended, Method 1 was completed by using a ruler to measure from the supporting surface to the posterolateral border of the acromion, a location that had been previously palpated and marked. Method 2 was similar to Method 1 except the elbow was fully flexed. Method 3 was completed with the subject in standing. A tape measure was used to measure from the coracoid process to the anterior sternocostal junction of the fourth rib, locations that had also been previously palpated and marked. Three measurements were taken by 2 examiners using each method with the subject changing out of and then returning to the test position between measurements. Results: Good intratester reliability was found for both examiners using Method 2 and Method 3 with Intraclass Correlation Coefficients (ICCs) of 0.953–0.963 for Method 2 and 0.997–0.998 for Method 3. Intertester reliability was good for Method 2 and Method 3 (ICCs = 0.842 and 0.832 respectively). The ICC for Method 1 was high for Examiner 1 (ICC = 0.976) but lower for Examiner 2 (0.775). Significant differences were found between mean values using Method 1 and Method 2 (p < 0.001). Poor and insignificant correlations were found between method 2 and method 3 (p = 0.298). Conclusions: Method 2 and method 3 have higher intratester and intertester reliability. However, methods 2 and 3 have poor correlation between them. Method 1 has lower intratester and intertester reliability than the other 2 methods. Practical Application: When monitoring PM flexibility, results suggest that measurements should consistently be performed by choosing either method 2 or method 3. Altering the method of measuring PM flexibility may result in the inability to recognize increased or decreased PM flexibility.

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48. Perceptions, Attitudes, and Vision Performance Scores of Collegiate Baseball Players after Participating in 3-D Vision Training

D. Szymanski,1 T. Light,1 Z. Voss,1 M. Greenwood,2 and J. Beam3

1Louisiana Tech University; 2Texas A&M University; and 3Santa Fe Community College

Purpose: To investigate the perceptions, attitudes, and vision performance scores of collegiate baseball players after 10 weeks of computer based 3-D vision training. Methods: Thirty-four male NCAA Division I baseball players (age = 20.0 ± 1.5 years, height = 183.9 ± 5.4 cm, body mass = 89.3 ± 9.2 kg, % body fat = 14.1 ± 3.7%) volunteered for this study. All players completed the same 14 question survey that asked them about their perceptions and attitudes of vision training before and after completing 3-D vision training. Questions on the survey related to visual acuity, peripheral vision, visual accommodation, eye alignment, eye-hand coordination, visual concentration, and depth perception. Before completing 3 vision training sessions per week (10–15 min/session) for 10 weeks using a commercial computerized software system, all players received verbal explanation and demonstration on how to complete the 3-D vision testing performed with a game pad controller on a computer from 2 of the principal investigators. 3-D vision testing and training consisted of numerous vision performance variables, such as eye alignment, depth perception, visual flexibility (convergence and divergence), visual recognition (accuracy and response time), and visual tracking (accuracy and response time). A nonparametric Wilcoxon Signed-Rank test, which detects differences in the distributions of 2 related variables, was used to determine if there was a significant difference between the pre and post-training survey questions. Paired sample t-tests were performed on all pre and post-training vision performance variables. Results: There were no statistical differences (p ≤ 0.05) between the pre and post-training survey questions. However, there were statistically significant differences in pre and post-training final edge scores (p = 0.000), depth perception (p = 0.003), convergence accuracy (p = 0.006), convergence station score (p = 0.001), divergence accuracy (p = 0.045), visual recognition response time (p = 0.000), visual recognition accuracy (p = 0.027), and visual tracking response time (p = 0.002). Conclusions: These data suggest that perceptions and attitudes of vision training did not change after 10 weeks of vision training, yet vision performance variables evaluated on a computerized software system significantly improved. Practical Application: Although vision performance variables on a computerized software program improved, it is not known if baseball offensive performance skills, such as batting average, slugging percentage, strike out percentage, and on-base percentage will be positively affected. Furthermore, it is very difficult to determine how improved vision skills affect baseball offensive performance since a hard hit ball could be categorized as a “success” even though it may result in an out. It is suggested that future vision studies attempt to determine which variables should be considered successful to determine if vision training actually enhances baseball offensive performance.

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49. Effects of Whole Body Vibration on Muscle Activity During Maximal Voluntary Isometric Contraction Following Exercise Induced Muscle Damage

N. Dabbs,1 H. Chander,2 V. Moreno,2 L. Brown,3 and J. Garner2

1California State University, San Bernardino; 2The University of Mississippip; and 3California State University, Fullerton

Enhancing lower-body performance is critical for many sports. Often athletes that undergo high intensity training experience delayed onset muscle soreness (DOMS), which leads to decreased performance. Many recovery modalities have been tested with conflicting results. Whole-body vibration (WBV) has previously been investigated as a recovery modality, however no previous research has investigated muscle activity following maximal voluntary isometric contractions (MVIC). Purpose: The purpose of this investigation was to determine the effect of WBV on muscle activity during MVIC following exercise induced muscle damage (EIMD). Methods: Twenty-seven healthy, recreationally trained women (age 21 ± 2 years, height 172.38 ± 92.27 cm, mass 58.67 ± 11.53 kg) completed 7 sessions (3 familiarization and 4 testing) and were randomly selected into a treatment or control group. WBV or control (no vibration) was administered each testing day. MVIC muscle activity was assessed via electromyography (EMG) before EIMD via split squats and every 24 hr up to 72 hours. Two sets of measures were collected each day, consisting of a pre measure followed by WBV or control, and then a second set of measures were taken. To assess muscle activity during the MVIC, bipolar electrodes were placed on the muscle belly of the vastus medialis (VM), medial hamstring (MH), tibialis anterior (TA) and medial gastrocnemius (MG). Root mean square (RMS) EMG values for MVIC were taken and then calculated into a percent change from the first day baseline measure; prior to EIMD. To test differences between groups and over time, a 2 × 11 (group × time) mixed factor analysis of variance was conducted for each variable. Results: No significant (p > 0.05) interactions or group differences were found for EMGrms %change during MVIC in all 4 muscles. No significant (p ≤ 0.05) main effect for time was found for TA and MG musculature. Significant (p ≤ 0.05) main effects for time were found for VMO and HM, indicating muscle activity declined following muscle damage. Conclusions: These results indicate that WBV does not aid in muscle activity recovery during a MVIC following exercise induced muscle damage caused by the resistance load and volume prescribed in this study. Practical Application: The current investigation did not show any positive effects utilizing WBV, however it did not see any negative effects either. Therefore, coaches and practitioners may or may not want to use WBV following EIMD to help aid in muscle recovery.

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50. An Examination of Antagonist Muscle Motor Unit Synchronization During Co-Activation

J. DeFreitas1 and T. Beck2

1Oklahoma State University; and 2University of Oklahoma

It has been suggested in the literature that the synchronous discharge of 2 motor units leads to a greater force twitch summation, and therefore, greater force production. Synchronization likely occurs when 2 motor units share 1 or more common inputs. Evidence that motor unit synchronization occurs has been well established in many muscles when acting as an agonist. However, very little is known about the motor unit firing properties of an antagonist muscle as it co-activates. Purpose: To investigate whether antagonist muscle motor units demonstrate synchronization during an isometric contraction, and if so, how it compares to the agonist muscle. Methods: Surface electromyography (EMG) from 15 participants was detected from the biceps brachii (BB; agonist) and triceps brachii (TB; antagonist) during an isometric elbow flexion at 60% of the subject's maximal voluntary contraction. The EMG signals were decomposed into their constituent motor unit action potential trains. The magnitude (Sync Index; %) of short-term synchronization (within 6 ms) was calculated for every unique motor unit pair (i.e., 1 vs. 2, 1 vs. 3, 2 vs. 3, etc…) for each contraction, and was measured as the % of extra firings that are synchronized beyond what would be expected from chance alone. Results: A total of 887 motor units were detected (457 from the BB; 430 from the TB). From those motor units, 8,574 unique comparisons were used for synchronization analyses (5,093 from the BB; 3,481 from the TB). Approximately 69% of the agonist motor unit pairs (3,517 out of 5,093) demonstrated significant short-term synchronization (i.e., a Sync Index > 0%) compared to 53.9% of the antagonist motor unit pairs (1,877 out of 3,481). Furthermore, the average sync index across subjects for agonist motor units was 10.24% compared to 7.9% in the antagonist motor units (p = 0.0077). Conclusions: The antagonist motor units demonstrated significant levels of short-term synchronization, but to a lesser extent than was exhibited by the agonist motor units. This suggests that antagonist motor units share common synaptic inputs with each other, but the synaptic strength or number of active inputs differs from that from the agonist motor unit pool. Practical Application: A lot of work still needs to be done to fully understand the neural mechanisms underlying antagonist co-activation, but this study provides some of the first insight of antagonist motor unit firing properties and how they differ from agonist motor control.

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51. Electromyographic Analysis of the Gluteus Maximus, Rectus Femoris, and Biceps Femoris During Three Variations of the Glute Bridge Exercise

R. Dudley, H. Bradburn, G. Noffal, and S. Lynn

California State University, Fullerton

It has been postulated that improving the function of the hip extensor muscles, primarily the gluteus maximus, could help improve the efficiency of human movement patterns. Furthermore, it has been theorized that during a hip extension exercise, an increase in the activation of the quadriceps muscle may, through reciprocal inhibition, reduce the activity of the hamstrings, and allow the glute to act as the dominant mover. Clinical use of various glute bridge exercises have attempted to strengthen the gluteus maximus, however no studies have determined the effect of different glute bridge techniques on glute, hamstring, and quadriceps activation. Purpose: To determine the effects of 3 different glute bridge techniques on glute, hamstring, and quadriceps muscle activity as measured by surface electromyography (EMG). Methods: Fifty-one subjects (age: 22.74 ± 2.65 years; height: 1.71 ± 0.1 m; mass: 74.45 ± 18.78 kg) were recruited for this study. Surface EMG electrodes were placed on the gluteus maximus (GM), biceps femoris (BF), and rectus femoris (RF) of the dominant leg. Maximum Voluntary Contraction (MVC) data was collected for each muscle. Subjects then performed 3 repetitions of 3 glute bridge conditions in random order. Conditions consisted of: Normal glute bridge; Band, a mini band was placed around the distal thighs, while subjects abducted in order to keep tension on the band; Stopper, subjects created an anterior shear force by pushing the feet forward into a stationary block. Subjects were given a 1-minute rest period between trials. EMG data was collected for each of the 3 conditions. Results: A repeated measures MANOVA revealed significant differences between conditions (λ = 0.264, F(6,45) = 30.941, p < 0.001). BF activity during the stopper condition (26.04 ± 2.66 %MVC) was significantly lower than the normal (32.32 ± 3.07 %MVC) and band condition (33.17 ± 2.71 %MVC) (p = 0.033). In addition, GM activity during the band condition (29.34 ± 2.38 %MVC) was greater than the normal (16.41 ± 1.55 %MVC) and stopper condition (17.16 ± 1.94 %MVC) (p < 0.001). RF activity was significantly lower during the band condition (3.01 ± 0.32 %MVC) (p = 0.029) and significantly higher during the stopper condition (11.62 ± 1.55 %MVC) (p < 0.001) when compared to the normal condition (3.52 ± 0.42 %MVC). Conclusions: Although the stopper condition was successful in eliciting greater activation of the RF while simultaneously reducing the activation of the BF, GM activity was unchanged. However, reducing the activity of the BF may have allowed the GM to function as the prime mover for hip extension during the stopper condition. This could be extremely beneficial for hamstring dominant individuals who are interested in developing more glute dominant movement patterns. The presence of the mini band was successful in increasing GM activity above normal, which can potentially be attributed to the external rotation component introduced during the band condition. Practical Application: This information could be used by practitioners to help strengthen glute deficient populations and encourage glute dominant movement patterns.

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52. Difference Between Youth and Collegiate Baseball Pitchers in the Kinematics and Kinetics of the Lower Limbs During Pitching Motion

M. Kageyama,1 T. Sugiyama,1 H. Kanehisa,2 and A. Maeda2

1Graduate School of Physical Education, National Institute of Fitness and Sports in Kanoya; and 2National Institute of Fitness and Sports in Kanoya

Purpose: This study aimed to clarify the differences between youth and collegiate baseball pitchers in the kinetic and kinematic parameters of lower limbs during pitching motion. Methods: Subjects were 32 youth baseball pitchers aged 12–15 years (YPG, 13.9 ± 0.6 years, 163.6 ± 8.2 cm, 54.1 ± 10.5 kg) and 30 collegiate baseball pitchers aged 18–22 years (CPG, 19.6 ± 0.9 years, 177.1 ± 5.0 cm and 72.7 ± 9.9 kg). After warm-up session, the participants performed fastball pitches 10 times from a portable pitching mound towards a strike zone marked on a home plate. Three-dimensional coordinates during the pitching were obtained using a motion analysis system (Eagle System, Motion Analysis Corporation, Santa Rosa, CA) with 12 Eagle cameras with a sampling rate of 500 Hz and a shutter speed of 2000 Hz. In addition, the ground-reaction forces (GRFs) of the pivot and stride legs were measured by the use of 2 multicomponent force plates (Z15907, 60 × 120 cm, Kistler Corporation, Winterthur, Switzerland), which were set in the portable pitching mound. Three-dimensional motion analysis with a comprehensive lower extremity model was used to determine kinematic and kinetic parameters during the pitching. The joint torques of hip, knee and ankle were calculated using the inverse-dynamics computation of musculoskeletal human models using motion-capture data. To eliminate any effects of variation in body size, kinetic and GRF data were normalized by dividing them by body mass. Differences in the measured variables between the youth and collegiate pitchers were tested using a Student's unpaired t-test. Results: The pitched ball velocity was significantly higher in SPG than in YPG (35.2 ± 1.9 m/s vs. 30.7 ± 2.7 m/s, p < 0.01). The most of kinematic parameters for lower limbs were similar between CPG and YPG. Maximum Fy (toward the throwing direction) on pivot leg, Fy and resultant forces on stride leg at ball release, and the joint torques of hip and knee were significantly greter in CPG than in YPG (p ≤ 0.05). Conclusions: The present study indicates that the kinematics of lower limbs during baseball pitching are similar between youth and collegiate pitchers, but the momentum of lower limb during pitching is less in youth pitchers than in collegiate pitchers, even when the difference in body mass was considered. Practical Application: The present study provides evidence that the difference in the pitched ball velocity between youth and collegiate baseball pitchers can be attributed to that in the momentum of lower-limbs rather than the kinematics. Notably, youth baseball pitchers cannot develop hip and knee joint torques corresponded to body size as compared to senior baseball pitchers. For youth pitchers, therefore, resistance exercises such as squats, the single-leg squats and the multi-directional lunges should be incorporated systematically into individual strength and conditioning programs.

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53. Test-Restest Reliability of Panoramic Ultrasound Imaging to Examine Fascicle Length and Pennation Angle in Older Men

C. Kleinberg,1 E. Ryan,1 J. Rosenberg,2 E. Sobolewski,1 M. Scharville,1 and A. Tweedell1

1The University of North Carolina at Chapel Hill; and 2The University of North Carolina–Chapel Hill

*Award Eligible—Master's Student Research Award for an outstanding poster abstract presentation.

The popularity of ultrasound (US) devices to examine muscle architecture has increased due to its ease of use and portability. Analysis of a single image obtained via panoramic imaging allows researchers to quantify muscle characteristics such as fascicle length (FL) and pennation angle (PA). These techniques appear promising; however consistency of these values in older adults with that display hyperechoic skeletal muscle US images warrants further evaluation. Purpose: The purpose of the present study was to determine the test-retest reliability for FL and PA assessed from a single image using the panoramic US technique in older adults. Methods: Twenty-three recreationally active older men (mean ± SD age 69 ± 3.2 years; height 176.4 ± 5.1 cm; mass 82.6 ± 10.9 kg) volunteered for this investigation. Participants visited the laboratory on 2 separate occasions separated by 2–7 days at the same time of day (±2 hours). Measurements were taken with the participants lying in the prone position with their leg fully extended and right foot securely attached to a vertical post at a joint angle of 90° between the foot and leg. The probe was positioned perpendicular to the skin and moved along the plane the fascicles of the medial gastrocnemius. A generous amount of water-soluble transmission gel was applied to the skin to reduce possible near field artifacts and enhance acoustic coupling. Panoramic images were obtained via LOGIQView software on a portable B-mode US imaging device, and all US images were analyzed off-line using Image-J software. Test-retest reliability for FL and PA were determined using Model 2, 1 to determine the intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimum difference (MD) values per recommendations of Weir (2005). Systematic error was examined using separate one-way repeated measures analyses of variance (ANOVAs). Results: The reliability statistics for FL and PA are presented in Table 1. Conclusions: The ANOVAs indicated no systematic error between days. Relative consistency was acceptable for ICC with values for FL and PA of 0.945 and 0.809, respectively. Additionally, absolute consistency was acceptable with SEM values (expressed as a percentage of the mean) for FL and PA of 4.25 and 6.52%, respectively. Minimal changes to be considered real for FL and PA were 0.69 cm and 3.07°, respectively. These findings demonstrate that panoramic US imaging may be a reliable technique for measuring FL and PA of the MG in older adults. Practical Application: Future studies may use panoramic US imaging to determine the effects of various training modalities on muscle architecture in older adults.

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54. Does Type of Ankle Brace Affect Performance in Jumping and Jump Phase Ground Reaction Forces and Loading Rates?

J. Kovaleski,1 W. Liu,2 M. Wilt,1 P. Hoppmann,1 C. Tygielski,1 and L. Gurchiek1

1University of South Alabama; and 2Auburn University

Biomechanical study of wearing ankle bracing during jumping is necessary to clarify effects on performance. Different types of bracing may have different degrees of influence based on design and brace material. Previous research on the effects of ankle bracing on jump performance primarily focused on the lace-up brace and changes in standing countermovement vertical jump (CMJ) height. Findings from these studies indicate that bracing does not meaningfully restrict height obtained during controlled vertical jumping, however outcomes from other studies have been inconclusive. Examination of other jumping tasks and biomechanical measures could show if and how bracing affects performance. No comprehensive analysis of repetitive jumping and jump phase ground reaction forces (GRFv) and loading rates associated with various brace types has been reported. Purpose: To compare the effect of type of ankle support on jump performance and jump phase ground reaction force and loading rate. Methods: Twenty athletes (21.7 ± 1.2 years, 80.9 ± 17.5 kg, 174.8 ± 9.8 cm) were randomly assigned and participated in all ankle support condition trials (no brace [NB], soft-shell brace; lace-up brace; and semi-rigid brace). They performed a 5-repetition CMJ and a 10-repetition ankle hop test wearing an accelerometer which measured jump height, cm; foot contact time, ms; reactivity, jump height/ground contact time; stiffness, kN/m; peak power, W/kg; peak force, N/kg; and peak velocity, cm/s. A maximal CMJ was performed on a force plate and jump phase unloading and loading GRFv (normalized to bodyweight; N/kg), time (s), and loading rates (N/kg/s) were assessed. Repeated Measures ANOVA's compared measures among no brace and braced trials across all jump tests. Results: The 10-rep ankle hop test for the lace-up brace showed a significantly lower mean jump height when compared with the no brace condition (21.4 ± 7.1 vs. 23.8 ± 6.4 cm, p = 0.015). There were no significant differences (p ≥ 0.05) for jump height, time of contact, reactivity, or stiffness among any of the brace conditions. No significant differences (p ≥ 0.05) for jump height, peak power, peak force, or peak velocity among ankle conditions were found for the 5-rep CMJ. In addition, no significant differences (p > 0.05) were found among the support conditions for maximal jump phase loading GRFv (NB: 23.2 ± 3.2 N/kg; soft-shell: 22.9 ± 2.2 N/kg; lace-up: 23.3 ± 2.7 N/kg; semi-rigid: 22.9 ± 2.7 N/kg); maximal jump phase unloading rate (NB: −17.9 ± 7.8 N/kg/s; soft-shell: −17.56 ± 9.2 N/kg/s; lace-up: −16.73 ± 8.4 N/kg/s; semi-rigid: −19.6 ± 11.5 N/kg/s) or for maximal jump phase loading rate (NB: 43.3 ± 22.0 N/kg/s; soft-shell: 39.8 ± 17.0 N/kg/s; lace-up: 41.8 ± 19.0 N/kg/s; semi-rigid: 40.6 ± 16.7 N/kg/s). Conclusions: Jump phase kinetics was not negatively affected by ankle bracing. Ankle-hop jump height involving the lace-up brace trail was the only performance variable affected. This finding illustrates differences between cyclical rebounding activities such as the ankle hop which involves primarily ankle joint motion to perform vs. the CMJ which involves greater knee and hip movements to perform. Practical Application: Our findings indicate a small impairment in jump performance when athletes wear external ankle support. Objective information on the effects of different types of bracing on jump performance may assist strength and conditioning and sports medicine professionals when recommending ankle bracing to an athlete.

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55. Effect of Start Procedure on the Relationship Between Wingate Performance and Other Standardized Power Tests

T. Thurston, A. Ciccone, X. Avila, B. Spiering, and D. Judelson

California State University Fullerton

Introduction: The Wingate Anaerobic Cycling Test is widely accepted as the gold standard for anaerobic power testing. Though a standardized start procedure exists, researchers and coaches have frequently utilized alternate protocols without previously identifying if these changes manipulate the relationship between Wingate performance and other standard power measures. Purpose: This study was to examine the relationships between Wingate performance and other standardized power tests using several Wingate start procedures. Methods: Twelve male recreational exercisers (age = 25.2 ± 4.1 years, mass = 76.2 ± 10.3 kg, height = 175.2 ± 9.3 cm, body fat = 14.5 ± 6.5%) completed vertical jump, 50 m sprint, and 3 Wingate experimental sessions. All Wingate trials began with a 5 minute warm-up that included 5 maximal sprints each lasting 5 seconds. During the final 5 seconds of the warm-up, subjects completed a ramped start (RS), constant load start (CLS), or dead start (DS) in counterbalanced order. During RS, participants increased pedaling rate from 60 to maximal rpm. During CLS, participants maintained a constant pedal rate of 60 rpm. During DS, participants did not pedal. Immediately after the 5 seconds lead–in, subjects pedaled maximally for 30 seconds against a resistance set at 7.5% of body mass. Results: For all conditions, absolute peak power correlated with vertical jump (RS, r = 0.858; CLS, r = 0.791; DS, r = 0.824; p ≤ 0.05 for all relationships), but relative peak power was not statistically related (p ≥ 0.05) to vertical jump. DS absolute peak power was significantly correlated (r = −0.623, p ≤ 0.05) to 50 m sprint time, however absolute RS and CLS peak power were not statistically related to sprint time (p ≥ 0.05). DS and CLS relative peak power (r = −0.714 and −0.586, respectively, p ≤ 0.05) were significantly correlated with sprint time, however RS relative peak power was not statistically related to sprint time (p ≥ 0.05). Conclusions: These findings indicated increases in Wingate power related to improvements in vertical jump and sprint performance. Even though all conditions strongly correlated with vertical jump, only the DS condition strongly related to both vertical jump and sprint time. Practical Application: These findings suggest that a DS lead–in might better inform coaches and strength professionals about power in a variety of sports and movements.

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56. Four Weeks of Detraining Significantly Decreases Power, Strength, and Sensorimotor Ability in Adolescent Surfers

T. Tran,1 L. Lundgren,1 J. Secomb,2 O. Farley,2 G. Haff,3 S. Nimphius,3 R. Newton,3 L. Brown,4 and J. Sheppard1

1Hurley Surfing Australia & Centre for Exercise and Sport Science, Edith Cowan University; 2Hurley Surfing Australia; 3Edith Cowan University; and 4California State University, Fullerton

It is well established that an adequate training stimulus will result in positive adaptations whereas lack of a training stimulus, either acute or long term, will result in a maladaptive response. However, the magnitude of maladaptation or detraining depends on other factors such as the athlete's level of training or training factors such as the intensity, volume, frequency, and duration associated with the detraining period. Purpose: To investigate the effect of 4 weeks of detraining on power, strength, and sensorimotor ability in adolescent surfers. Methods: Nineteen adolescent surfers with an overall mean age, mass, and stature (mean ± SD) of 13.84 ± 1.71 years, 53.59 ± 10.76 kg and 165.12 ± 8.89 cm, respectively, volunteered to participate in this 4-week detraining study following 7 weeks of periodized resistance training. Athletes continued their surf training sessions but did not complete any resistance training throughout the detraining period. Power (vertical jump height; VJH), maximal isometric strength (isometric mid-thigh pull; IMTP), and sensorimotor ability (time to stabilization during a drop and stick (DS); TTS) pre-test results were determined from the conclusion (post-test) of the first 7-week training block while post-test results were measured at the start (pre-test) of a second 7-week training block. In other words, the 4-week washout period between 2 seven-week training blocks was used to assess the effect of a detraining period. Athletes performed 3 countermovement jumps to self-selected depth, 3 IMTP, and 5 DS trials. The best trial for each variable was used for further analysis. Results: Paired t-test revealed that 4 weeks of detraining significantly decreased all the following variables: VJH by −5.26%, (p = 0.037, d = 0.40), vertical jump peak velocity by −3.73% (p = 0.0002, d = 0.51), maximal isometric strength by −5.5%, (p = 0.012, d = 0.22), and relative maximal isometric strength by −7.27% (p = 0.003, d = 0.47). Furthermore, sensorimotor ability worsened, as assessed by TTS, with a significant increase of 61.36% (p = 0.004, d = 1.01), thus indicating the athletes took longer to stabilise during a dynamic landing task. Conclusions: In light of these observations, adolescent surfers experienced significant detraining effect when resistance training was discontinued for 4 weeks. This demonstrates that surfing, in the absence of resistance training, is not sufficient training stimulus for maintaining power, strength, and sensorimotor ability. Practical Application: Adolescent surfers with a relatively low training age should avoid cessation of resistance training and strive to maintain consistent resistance training in conjunction with surf training to avoid negative impacts on power, strength, and sensorimotor ability, as these effects will reduce performance and increase injury risk.

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57. Mini-Hurdle Drill Transiently Improves Sprint Performance in Sprinters

T. Yoshimoto, Y. Takai, H. Kanehisa, and M. Yamamoto

National Institute of Fitness and Sports in Kanoya

Purpose: Maximal running velocity (Vmax) is one of the determinants in 100-m race. Sprinters and their coaches a have great interest in training program for improving of Vmax. To enhance Vmax, a variety of drills (e.g., drills with box and mini-hurdle and bounding) are included in not only regular training program but also warming-up before competition. However, less information on transient, short- and long-term effects of such a drills on Vmax are available from earlier studies. Hence this studies study aimed to clarify the transient effects of the different drills on sprint performance in collegiate sprinters. Methods: This study was randomized and longitudinal design. Ten male sprinters (20.3 ± 1.1 years; 174.6 ± 4.6 cm; 65.8 ± 4.2 kg; 100-m personal best time, 11.53 ± 0.52 seconds, means ± SDs) performed 3 different drills: mini-hurdle, bounding, and control conditions. In the mini-hurdle condition, the participants ran over 10 × 10 mini-hurdles (height, 22 cm; width, 90 cm) as fast as possible. In the bounding condition, the participants performed 3 × 50-m bounding jump as explosive and far as possible with interval of 3 minutes. In the control condition, the participants performed 2 × 50-m sprint with interval of 5 minutes. Before and after each condition, Vmax, stride length, and step frequency in 50 m (a high-speed camera: 300 frames/s), and blood lactate (fingertip) were determined. During the trial sessions, heart rate was measured by electrocardiogram (ECG). Results: There was no significant difference in Vmax before intervention among 3 conditions, and the intra-class correlation coefficients were 0.953–0.972 for Vmax, indicating that the measurement of Vmax was reproducible in this study. The Vmax (+0.31 m/s) and maximal step frequency (+0.31 Hz) in 50-m was increased after the mini-hurdle condition, but not after the other conditions. The stride length did not change after conditions. There was no significant difference in heart rate immediately after-intervention among 3 conditions, indicating that physiological stress was the same among all conditions. Blood lactate after intervention was the highest in the control condition, and was the lowest in the mini-hurdle condition. Change in the blood lactate was not related to that in the Vmax in each condition, suggesting that the influence of muscular fatigue on the change in Vmax would be less. Conclusions: The current finding indicates that mini-hurdle drill transiently improves maximal velocity in sprinter. This change may be attributed to increase in step frequency. Practical Application: The drills used in this study are often performed in not only regular training but also warming-up before competition for sprinter. Since the current findings shows that mini-hurdle drill transiently enhances maximal velocity, we suggest that mini-hurdle drill should be added to conditioning program for warming-up before competition.

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58. An Exploratory Examination of the Relationship Between Traditional Pushups, Hand-Release Pushups, and One-Repetition Maximum Bench Press Performance

C. Allen,1 A. Hatchett,2 J. Lundahl,1 B. Turnage,1 H. Chander,1 V. Cazas-Moreno,1 J. Garner,3 and R. Arpin2

1University of Mississippi; 2Franklin Pierce University; and 3The University of Mississippi

Introduction: The traditional pushup (TPU) has been used to develop upper body strength in untrained individuals as well as to develop and assess local muscular endurance in trained individuals. The hand-release pushup (HRPU), a pushup variation used in various exercise competitions to standardize range of motion (ROM), is untested as a viable field assessment tool for local muscular endurance or as a potential predictor of upper body strength. Purpose: The purpose of this study was to investigate the relationship between TPU performance, HRPU performance, and one-repetition maximum (1RM) bench press performance. Methods: 87 recreationally trained males (age 20.6 ± 1.9 years; height 176.3 ± 7.0 cm; mass 78.9 ± 10.3 kg) and 35 females (age 21.2 ± 1.2 years; height 164.5 ± 6.4 cm; mass 63.5 ± 12.9 kg) completed the study. Upon the procurement of informed consent, anthropometric measurement was taken and assessment protocol familiarization was provided. All participants performed the maximal upper body strength assessment. Following a 15-minute rest period, participants were randomly assigned to either a TPU assessment or a HRPU assessment. Both pushup assessment protocols were NSCA pushups-to-failure protocols. The use of a metronome was included to standardize the concentric and eccentric phases of the movement at 45bpm for TPU and 40bpm for HRPU respectively. The difference in metronome cadences was to allow for the removal and return of the hands to the floor that is required of the HRPU. A Pearson's correlation coefficient estimation was conducted to assess the relationship between the number of repetitions completed for each respective pushup type and maximal upper body strength. Independent t-tests were used to determine if there was a statistically significant difference between the 2 pushup groups as well as Levene's test of equality of variance to determine if a statistically significant difference in variances was present. Results: Analyses revealed a statistically significant correlation between 1RM bench press performance and both pushup types (HRPU = 0.612 and TPU = 0.559; p < 0.01). Independent sample t-test indicated no statistical significance between the 2 pushup types (p = 0.241). Furthermore, Levene's test of equality of variance revealed no significant difference in variances. Conclusions: Although implemented for the purposes of standardizing ROM in exercise competitions, the emergence of the HRPU may have ramifications on procedures currently implemented when using TPUs to assess local muscular endurance as well as potentially providing a safer and more economical way of assessing muscular strength. Practical Application: The HRPU can offer an increase in the standardization of ROM during upper extremity muscular endurance assessment as well as decrease the opportunity for inappropriate contact between the client/athlete and trainer/coach. The use of the HRPU as a method to predict upper extremity strength also appears feasible. Further research is necessary to generate specific prediction equations and determine the variables necessary to include in said equations.

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59. Pull-Ups: Strength or Endurance?

J. Clemons,1 J. Guillory,2 P. Smoak,2 and N. Richard2

1Department of Kinesiology, University of Louisiana at Lafayette; and 2University of Louisiana at Lafayette

Purpose: The purpose of this investigation was to identify the muscular fitness construct assessed using a maximum pull-up (PU) test. The overarching hypothesis for this study was that a maximum PU test is more likely a test of strength relative to body mass rather than endurance. Methods: Sixty college age males and females (n = 47 & 23, respectively) participated in the study. One PU test to failure was administered and scored using 3 different methods: traditional (i.e., number of full ROM pull-ups), fractional (i.e., 0.5 points if failure occurs at 90° ± 5° of elbow flexion, 0.25 points below the same point or 0.75 points above it). Scores were also computed for work: Work (Nm) = #pull-ups · vertical distance in meters · body mass · 9.81. Criterion measures for absolute and relative strength were 1 repetition maximum (1RM) lat pull downs and 1RM transformations: Relative Strength = 1RM ÷ Body Mass. Grip widths were held constant at 120% of biacromial breadth. PU and 1RM tests were separated by no less than 4 days and no more than 1 week. A warm-up of choice was allowed for PUs. The 1 RM was preceded by 2 unsupervised sets at 50% and 60–80% of the 1RM, respectively. Results: Pearson product moment correlation was used for analysis purposes. Bonferroni adjusted alpha levels of 0.00625 were adopted for 8 relationships of investigative interest for both males and females. For females, results indicated all 4 methods of scoring PUs were not significantly related with the 1RM (<0.34). For males, traditional pull-ups and fractional PUs were moderately related to absolute strength (r = 0.468; prob. < 0.0001). Traditional PU work and fractional PU work were the strongest correlates with absolute strength (i.e., 0.64 and 0.65, respectively). Overall, the strongest validity coefficients observed were when PU performance was correlated with relative strength. All correlations, for both males and females, were statistically significant (prob. < 0.0001) and ranged from 0.72 to 0.86. For men, the strongest was with traditional scoring (r = 0.86) and for females the strongest was with fractional scoring (r = 0.81). All PU tests were conducted to failure and no test exceeded 60 seconds; therefore, there was little scientific rationale to consider the hypothesis that PU performance was related to muscle endurance. Conclusions: For females, PUs were not related to absolute strength; however with males, they were moderately related. When PU work was considered, the relationship strengthened but still not to the level of acceptable validity. If the goal is to use PU performance to gain insight into absolute strength, a mixed sex, multiple regression equation may be used: 1 RM kg = (1.715 · # fractional PUs) + (0.753 · body mass) + (15.843 · sex) − 14.094, where sex is 1 for females and 2 for males, (R = 0.94 and a root mean square error ±6.1 kg). Using this equation, no significant difference was found between actual and predicted 1 RM tests. Practical Application: Knowledge of the construct purportedly being measured by a muscular fitness field test is essential. Strong evidence has been provided that suggests all participants tested by PUs, using either traditional or fractional scoring methods, should be advised that test results are most strongly related to ratio scaled relative strength and neither absolute strength or endurance.

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60. Training Type Augments the Internal: External Training Load Ratio in Male Basketball Players

V. Dalbo,1 P. Tucker,1 K. Young,2 and A. Scanlan1

1Central QLD University; and 2Wichita State University

Purpose: A variety of training load (TL) approaches have been developed which measure the physiological stress imposed upon players (internal TL) and the physical training stimulus (external TL). Currently, the preferred approach to monitor TL in basketball has not been established. Consequently, basketball coaches and conditioning professionals often measure internal or external TL in isolation, or in combination but with separate analyses. However, the integrated use of internal and external TL may provide practical insight regarding player response to the training stimulus. Therefore, the purpose of this study was to describe and compare the internal:external TL ratio during different types of basketball training. Methods: Seven semi-professional male basketball players (age: 25.7 ± 6.6 years; stature: 188.3 ± 6.6 cm; body mass: 92.1 ± 13.2 kg) were monitored during the general and specific preparatory phases of the annual training plan. The general phase involved basketball-specific, field-based interval training. The specific phases involved a variety of on-court conditioning drills aimed at developing player speed, power, agility, intermittent endurance, and anaerobic capacity. Player heart rates were collected across each training session to calculate internal TL using the summated-heart-rate-zones (SHRZ) approach. Triaxial accelerometers were affixed to each player on the posterior surface of the torso and were used to calculate external TL via the accumulated instantaneous rate of change in acceleration in the 3 movement planes (ACC). All TLs were reported in arbitrary units, and the internal:external TL ratio was presented as a decimal figure. To balance training distribution, each player had 2 random sessions sampled from each training type (total: N = 28; general preparatory: n = 14; specific preparatory: n = 14). Differences in the internal:external TL ratio between training type were assessed using dependent-sample t-tests. Results: The mean ± SD internal:external TL ratio across the specific phase (0.029 ± 0.004) was significantly greater (p < 0.001) than that observed across the general phase (0.021 ± 0.004). Conclusions: The present results indicate the internal:external TL ratio varies with training type in basketball players. Specifically, on-court conditioning drills appear to disproportionately increase the physiological demands relative to the training stimulus compared with interval linear running/sprinting drills. This difference may be due to the frequent execution of static muscle actions, upper-body movements, and shuffling activity during on-court training, which appear to represent as lower whole-body accelerations relative to the heart rate response experienced by players. Practical Application: This study highlights the benefit of combining internal and external TL approaches when monitoring TL in basketball players. In particular, reliance on accelerometer technology may not be representative of the actual stress imposed on basketball players during basketball-specific conditioning. Furthermore, basketball coaches and conditioning staff are recommended to determine individual player ratios during specific training types to more precisely detect abnormal training responses that require intervention. Acknowledgments: The technical expertise and involvement of the Rockhampton Rockets basketball coaching staff and players were essential in the completion of this study.

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61. Effects of Clothing Fabric and Construction on Thermal Stress During Exercise in the Heat

K. Allen,1 J. Davis,1 and M. Laurent2

1University of Montevallo; and 2Bowling Green State University

*Award Eligible—Undergraduate Student Research Award for an outstanding poster abstract presentation.

Purpose: Manufacturers have marketed sport textiles of synthetic fabrics to have superior properties for keeping wearers cooler, drier, and more comfortable compared to natural fabrics (i.e., cotton). The impact various clothing fabrics and the construction of the fabrics would have on thermoregulatory response is not well understood. Therefore the purpose of this study was to examine rectal temperature (Trec), mean skin temperature (Tsk), body temperature (TB) and heart rate (HR) response while exercising in a hot environment with synthetic vs. natural fabrics. Methods: Eight collegiate male athletes completed a treadmill

peak test, and then, in a randomized, counter-balanced order, 3 bouts of 0.60% of

peak (45 minutes total) at 32 °C. Participants wore 3 different t-shirt fabrics during the exercise trial. The fabrics consisted of 100% cotton, 50% cotton and 50% soybean protein fiber, and 100% polyester fiber with large mesh loops to facilitate ventilation through the clothing. Results: Repeated measures ANOVA revealed no significant main effect for clothing condition on rectal temperature (p = 0.43; synthetic 38.3 ± 0.2, cotton 38.2 ± 0.3, soy 38.1 ± 0.2 °C), mean skin temperature (p = 0.83), or body temperature (p = 0.61). Moreover, no significant main effect was found for HR (p = 0.94; synthetic 153 ± 28, cotton 154 ± 28, soy 154 ± 26 bpm) between clothing. Conclusions: Clothing fabric type or construction of the fiber had no significant effect on reducing thermal strain (Trec, Tsk, TB) or HR compared to a natural fabric (100% cotton) during exercise in a hot environment. Practical Application: This study confers with previous research that clothing fabric, whether synthetic or a blend of natural fabrics (soy/cotton), or fabric construction offer no thermoregulatory advantage in keeping wearers cooler compared to traditional cotton fabrics when exercising in the heat.

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62. Differences in Reaction Time Between female Collegiate Athletes

V. Moreno,1 H. Chander,2 C. MacDonald,3 N. Dabbs,4 C. Allen,2 H. Lamont,5 and J. Garner1

1The University of Mississippi; 2University of Mississippi; 3Coastal Carolina University; 4California State University of San Bernardino; and 5California Lutheran University

*Award Eligible - Doctoral Student Research Award for an outstanding poster abstract presentation.

Reaction time is an important component of athletic performance that contributes to overall success in sports relying on speed and agility. Athletes who are able to react faster to perturbations may be more suited to translate reaction time into performance enhancements, such as improved balance during directional changes or vertical jumps. Purpose: The purpose of this study was to investigate the active reaction time differences among soccer, volleyball and dance athletes as a perturbation was delivered during the motor control test (MCT). Methods: Twenty-one NCAA Division I soccer, (n: 10, age: 19.6 ± 1.3 years, height: 165.9 ± 4.8 cm, body mass: 63.7 ± 8.7 kg); volleyball, (n: 6, age: 19.8 ± 1.0 years, height: 179.9 ± 5.1 cm, body mass: 76.1 ± 14.1); and dance athletes, (n: 5, age: 20.3 ± 1.8 years, height: 163.4 ± 0.3 cm, body mass: 56.8 ± 6.4 kg), completed the study. Reaction time was determined during the MCT test via the NeuroCom Equitest (NeuroCom International, Inc. Clackamas, OR), this system has 18 × 18 dual force plates with translational capabilities. The MCT test measured the time between the onset of the translation and the participant's response to that perturbation. The MCT test consisted of small, medium and large perturbations in both forward and backward horizontal translations, creating 6 conditions. The 6 different conditions were; (a) backward small, (b) backward medium, (c) backward large, (d) forward small, (e) forward medium, (f) forward large movements. During the testing session each participant was instructed to stand as still as possible. As the translations occurred the involuntary reaction was measured through the force plate. Results: A one-way ANOVA demonstrated that there was a significant difference (p ≤ 0.05) between the female soccer, volleyball and dance athletes tested. Significant differences were shown during the backward small (p < 0.02) and large (p < 0.001) translations and forward large (p < 0.01) translation. A post hoc comparison (p ≤ 0.05) further revealed that both the soccer and the volleyball athletes demonstrated a smaller latency in reaction time in comparison to the dance athletes during these translations. Conclusions: Soccer and volleyball athletes demonstrated a quicker reaction time, which may be explained by their training history and movements required of their sport, such as cutting and change in direction. There is a greater need of these specific movements in soccer and volleyball as opposed to dancers. The results of this study indicate the dancers have a slower reaction time, which may be explained by the reaction time within specific trained movements, as dance may require more precision, planned movements as opposed rapid, unexpected manipulations of the body's center of mass. Practical Application: Athletes' should incorporate exercises such as change in direction, full body reaction times, and unstable surfaces, which may help improve response times to full body perturbations leading to better overall performance.

Saturday Podium Presentations

Saturday, July 12, 2014, 8:30 AM–8:45 AM

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1. Short-Term Strength and Plyometric Training Improves Eccentric Phase Kinetics in Jumping

C. Capps, K. Kijowski, C. Goodman, D. Knorr, T. Erickson, T. Triplett, O. Awelewa, and J. McBride

Appalachian State University

Purpose: The purpose of this investigation was to examine the effect of an abbreviated strength and plyometric training program on force- and power-time curve variables during jumping. Several previous investigations have indicated the type and length of training may influence whether changes occur in either concentric or eccentric variables. The purpose of this investigation was to examine a large number of force- and power-time curve variables, including average curves from all subjects, to determine the possible differential effect of short-term strength and plyometric training on eccentric and concentric phase kinetics. Methods: Nineteen male subjects were assigned to either a training (TG, n = 9) or control group (CG, n = 10). Training consisted of performing 3 sets of 3 repetition squats (90% of 1RM) and 5 sets of 6 repetition drop jumps from 40 cm twice per week for 4 weeks. A 1 repetition maximum in the squat (1RM) and countermovement (CMJ) and static jump (SJ) performance was assessed before (Pre) and after (Post) training. Squat 1RM attempts were performed to a knee angle of 80°. Each jump was performed on a force plate with a weightless bar across their back attached to 2 linear position transducers. Several variables were analyzed for individual subject force- and power-time curves for the jumps. Analog signals from the force plate and LPTs were collected for every trial at 1000 Hz using a BNC-2010 interface box with an analog-to-digital card. Custom virtual instruments were designed using LabVIEW and used for recording and analyzing data. Average force- and power-time curves for all subjects combined were also analyzed. Results: Absolute (Pre TG = 105 ± 19 kg, Post TG = 120 ± 15 kg) and relative (Pre TG = 1.32 ± 0.21, Post TG = 1.51 ± 0.15) squat strength significantly increased in TG (p ≤ 0.05). Calculation of variables from individual subject force-time curves during the CMJ indicated a significant decrease in eccentric time (Pre TG = 0.67 ± 0.12 seconds, Post TG = 0.54 ± 0.09 seconds, minimum force (Pre TG = 388 ± 96 N, Post TG = 185 ± 80 N) and eccentric impulse (Pre TG = 146 ± 44 N·s, Post TG = 97 ± 30 N·s) and significant increase in eccentric phase rate of force development (Pre TG = 3,492 ± 1757 N/s, Post TG = 5,229 ± 1945 N/s). Analysis of individual power-time curves in the CMJ also revealed a significant decrease in minimum power (Pre TG = −1,449 ± 380 W, Post TG = −1,930 ± 407 W), eccentric work (Pre TG = −270 ± 68 J, Post TG = −211 ± 105 J) and eccentric rate of power development (Pre TG = 18,038 ± 5,943 W/s, Post TG = 22,253 ± 6,303 W/s). Observed differences in the average force- and power-time curves for all subjects showed significant differences reflecting changes in the variables measured from individual curves. No significant changes occurred in the variables measured for the SJ. There were no significant changes for any of the variables measured in CG. Conclusions: This investigation indicates that short-term strength and plyometric training results in a significant change in eccentric phase kinetics as represented in both individual force- and power-time curves and average curves from all subjects combined. As shown by the lack of changes in SJ performance variables short-term training may initially result in eccentric phase kinetic changes followed by concentric phase kinetic changes after a longer time frame of training. This could possibly be due to early onset neural adaptations as opposed to the slightly delayed muscular adaptations that follow. Practical Application: When monitoring the effectiveness of a strength and plyometric training program focus on the analysis of eccentric phase variables is an important component for consideration. Changes in eccentric phase capabilities in short-term training may be a greater contributor to performance changes as opposed to concentric phase variables. This would indicate that the initial improvements in the stretch-shortening cycle are premeditated by eccentric phase capabilities.

Saturday, July 12, 2014, 8:45 AM–9:00 AM

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2. Bat Swing Speed of Collegiate Baseball Hitters With Different Muscular Strength and Grip Types

T. Higuchi,1 N. Miyamoto,2 T. Nagami,3 T. Isaka,1 and K. Kanosue3

1Ritsumeikan University; 2National Institute of Fitness and Sports in Kanoya; and 3Waseda University

Purpose: This study investigated bat swing speed of baseball hitters with different grip types and maximal force produced with bat-swing-like posture, in order to clarify the influence of bat grip and muscular strength on the hitter's bat swing speed. Methods: Thirty-three male collegiate baseball players (mean ± SD; years of experience = 12.7 ± 2.3 years, body weight = 72.9 ± 5.9 kg, height = 1.74 ± 0.05 m) were recruited for this study. After a practice session, participants hit a baseball off a tee with 2 types of bat grip (normal grip and choke-up grip) for 5 times each. For the choke-up grip condition, participants were instructed to put their small finger of the lead hand 65 mm above the grip end. For the measurement of maximal muscular strength produced with bat-swing-like posture, participants pulled on a handle with a steel wire rope connected to a wall for approximately 3 seconds by using their lead hand. Then, they pushed the handle for approximately 3 seconds by using their trail hand. After a 1-minute rest, same measurements for both hands were conducted again. By using a strain-gage load cell, tension force within the steel wire rope was measured. The sum of the greatest force recorded for each hand was defined as their maximal muscular strength with bat-swing-like posture. Bat swing speed 1 ms before the ball-bat impact was calculated from the images of swung bat captured by 2 high-speed digital video cameras with record rate of 1000 frames per second. Results: In normal grip condition, bat swing speed was significantly greater compared with choke-up grip condition (34.4 ± 1.6 m/s vs. 33.9 ± 1.5 m/s, respectively) (p < 0.001). The maximal muscular strength produced with bat-swing-like posture was 636.9 ± 77.4 N. There was a significant positive correlation between bat swing bat swing speed with normal bat grip and maximal force produced with bat-swing-like posture (R = 0.67, p ≤ 0.05) (Figure 1). Conclusions: Both the types of bat grips and ability to produce force with bat-swing-like posture can influence bat swing performance of collegiate baseball hitters. The use of choke-up grip can result in about 1.5 percent decrease of bat speed. In addition, the amount force produced with bat-swing-like posture was positively correlated to the hitters' bat swing speed. Practical Application: Findings of this study suggest the ability to produce greater force with bat-swing-like posture is related to the ability to swing a bat faster. It is possible that improving muscular strength which contributes to produce force with bat-swing-like posture increases hitters bat speed. In addition, negative effect of the use of choke-up grip to the bat speed should be considered with other relevant variables such as bat swing time and bat swing accuracy. Acknowledgments: This study was supported by Grant-in-Aid for Japan Society for the Promotion of Science Fellows.

Saturday, July 12, 2014, 9:00 AM–9:15 AM

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3. Preliminary Investigation Into the Association of Longitudinal Foot Dimensions With Countermovement Vertical Jump Displacement

L. Weiss,1 J. Caia,2 J. Harry,2 L. Chiu,3 B. Schilling,2 and M. Paquette2

1The University of Memphis; 2University of Memphis; and 3University of Alberta

The calcaneal tendon generates force to overcome reaction forces acting at the talus and the distal foot. The force in the calcaneal tendon depends, in part, on the moment arm lengths the reaction forces act through. Therefore, variations in foot dimension may contribute to differences in vertical jump performance. Purpose: To determine the association between 2 different longitudinal foot dimensions and countermovement vertical jump (CMJ) displacement. Methods: Fifteen young, healthy men (body weight: 84.52 ± 8.58 kg; stature: 1.79 ± 0.07 m) with plyometric jump training experience were participants in the study. Each engaged in 2 testing sessions separated by 24 or 48 hours to control for diurnal variations. Subjects were also well rested beforehand to control for any exercise effects. Sliding digital calipers were used to measure the anterior-posterior distance between the posterior aspect of the calcaneus and the: (a) talocrural and (b) metatarsophalangeal joints. Measures were obtained bilaterally with subjects in each of the following 3 conditions: non-weight bearing, bilateral weight bearing, and unilateral weight bearing. Both absolute and body-height normalized data were included in the analysis. CMJ displacement was assessed during the second session after all foot dimension measurements were taken. Associations between CMJ and foot dimensions were assessed using bivariate correlations. Results: The average CMJ displacement was 0.48 ± 0.11 m. The average calcaneus-to-metatarsophalangeal joint length ranged from 18.6 ± 0.8 to 19.0 ± 0.9 cm under the 3 loading conditions. The average calcaneus-to-talocrural joint length ranged from 5.3 ± 0.4 to 5.5 ± 0.5 cm under the same conditions. CMJ displacement was inversely associated with both body weight (r = −0.35) and stature (r = −0.13). Other relevant findings are presented in Table 1. Conclusions: CMJ displacement is multifactorial; therefore, it was expected that the proportion of shared variance explained by absolute and normalized longitudinal foot dimensions would be small. Correlations, as expected, were low but generally inverse, accounting for between 0 and 17% of CMJ displacement. These associations should be explored further using larger sample sizes. Practical Application: Although only a small amount of variability appears to be explained using the foot dimensions described herein, these measures are likely to be untrainable and may help determine each person's maximum potential for improving vertical jump performance.

Saturday, July 12, 2014, 9:15 AM–9:30 AM

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4. Predicting Caliber of Performance and on Field Contribution of NAIA Division Football Players

G. Ryan,1 G. Long,1 J. Walker,1 R. Herron,2 S. Bishop,3 and C. Katica4

1University of Montana Western; 2The University of Alabama; 3Texas A&M University–Commerce; and 4Pacific Lutheran University

Accurately predicting sport performance is a highly variable and valuable measurement and evaluation issue. Coaches and scouting personnel often use performance in the weight room and on-field drills to determine an athlete's aptitude for a given sport or position. The National Football League conducts annual combines to assess athletic ability in a variety of tests (40 yard [yd] dash, vertical jump, 20 yd shuttle, etc). Rarely are these data normalized and combined to determine an athlete's overall potential in their sport relative to their competitive peers. Purpose: The purpose of this study was to combine and normalize off-season performance tests of 70 NAIA football athletes to determine if a prediction of on-field contribution could be estimated using off-season testing with Z-scores. Methods: Athletes completed a 5 test battery of vertical jump, hang clean max, squat max, 10 yd dash, and 20 yd shuttle. Athletes were separated by position grouping: Bigs (OL, DL), Middles (RB, QB, TE, LB), and Littles (WR, DB). Additionally, athletes were grouped by previous season contribution level: Starter, Contributor, Projected Starter/Contributor, or Bench. Z-scores were obtained for each variable tested and combined to form a 5 test Z-score value for each athlete. Average 5-test Z-scores were compared for each position grouping and contribution level using an ANOVA, with post-hoc t-tests conducted on all significant findings. Results: A significant omnibus result was observed between all groups (p = 0.01). Starters (Z = 1.43) and Contributors (Z = 2.19) had higher 5-test Z-scores than Projected Starter/Contributor (Z = 0.52) and Bench (Z = −1.24) players. This finding held true for all position groups except Littles (p = 0.13). Conclusions: The findings of this study suggest that the off-field testing battery did account for some variance in determining the caliber of on-field performance and contribution in NAIA football players. In all groupings (Bigs, Middles, Littles), Bench players had combined 5-test Z-scores below average (Z < 0.00). Practical Application: These findings may set a standard for colleges and athletes to assess performance and determine where opportunities for improvement, warrant well-designed strength and conditioning programs that translate into greater success on the field.

Saturday, July 12, 2014, 9:45 AM–10:00 AM

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6. Personal Trainers as 21ST Century Exercise Scientists: Evidence-Based Rationale

S. Bishop,1 and J. Casey2

1Texas A&M University–Commerce; and 2The University of Alabama

Personal training (PT) is a profession focused on individual exercise assessment and prescription. With books, workout videos and television shows, personal trainers are arguably the highest profile physical educator under the kinesiology umbrella. Purpose: The purpose of this presentation is to examine the literature associated with PT and present a case for an academic standard in this increasingly more influential profession. Methods: A review of the literature was performed examining the personal training profession. Articles were further stratified to include the related topics of education level, client injury prevalence, client satisfaction and related litigation of personal trainers. Results: Currently, there are no consistent academic standards in the fitness industry for personal trainers. Though all certifications require a culminating test, other requirements for PT certification can range from a high school diploma and CPR certification to week-long seminars. Because organizational membership dues and testing fees help fund these organizations, the ultimate goal is not to reduce, limit, or eliminate these fees or organizations. Conclusions: Current research supports the idea that the personal training profession is neither inferior nor separate from kinesiology, but a formidable influence in the field of exercise science. Practical Application: As a result of this review, it is the view of the authors that a symbiotic relationship can be created between academic institutions and the governing bodies of the fitness industry. These findings could lend themselves in furthering the conversation and potential legislation of increased PT standards in the form of developing uniform national certification and minimum education requirements.

Saturday, July 12, 2014, 10:00 AM–10:15 AM

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7. Effects of Standing vs. Seated Recovery Position on Heart Rate Palpation Accuracy Following a Three Minute Step Test

K. Huet,1 A. Bosak,1 M. Kenreich,1 A. Mitchell,1 and P. Vinegas2

1Armstrong Atlantic State University; and 2Armstrong Atlantic State University and United States Army Reserves

Prior studies have evaluated the accuracy of subjects palpating their carotid heart rate (HR) immediately following submaximal exercise. The 3 minute step test is a test where subjects palpate their post step test recovery HR in the traditional standing position. Post-exercise recovery HR has an important and symbiotic relationship with step tests and accurate palpation of the recovery HR is extremely important for the development of more precise cardiovascular exercise programs. Yet, it appears that prior research studies have not assessed subjects' accuracy of palpating their HR when in a different recovery position following a 3 minutes step test. By changing the recovery position immediately after the completion of a 3 minutes step test, from a standing to a seated position there by activating less muscle mass, the subject's recovery HR may potentially be lower. This might, in turn, contribute to a more accurate palpation count since there would, in theory, be less beats to count and therefore less of a chance to miss counting a heartbeat. Purpose: To evaluate subjects' ability to accurately palpate their 3 minutes step test recovery HR when resting in a standing vs. seated position. Methods: Thirty-eight above averagely fit subjects (20 males and 18 females) were connected to an Electrocardiogram (EKG) and completed two 3-minute step tests at a cadence of 24 (male cadence) or 22 (female cadence) steps/min, separated by 48–72 hours, in a counterbalanced order. Upon completion of the 3 minutes step test, subjects palpated their HR, while in a standing or seated position, at the carotid artery site within 5 seconds and then counted their post step test recovery HR for the next 15 seconds. Results: The post step test recovery EKG HR (seated = SEekg and standing = STekg) was compared with their respective post step test recovery palpated HR (seated = SEpal and standing = STpal) using MANOVA statistical methods with significant differences considered at p ≤ 0.05. Differences between SEekg vs. SEpal (33.7 ± 6.0 bts vs. 34.2 ± 5.9 bts, p = 0.199) and STekg vs. STpal (35.4 ± 5.3 bts vs. 35.8 ± 5.2 bts, p = 0.250) were not significant. Also, average palpated beats off from EKG values during the 15 seconds post step test recovery HR palpation period were ±2.00 (SEpal) and ±2.18 (STpal) respectively. Conclusions: The results suggest that subjects palpated their SEpal slightly more accurately than STpal, but it appears as though either recovery position will produce similar palpation results pertaining to the number of beats that subjects were off from the EKG count. Despite the slight differences, subjects were not 100% accurate at palpating their post step test recovery HR when compared to the EKG recording. Furthermore, mean overall palpation count (i.e., number of beats counted in the 15 seconds period) was lower for SEpal vs. STpal. Practical Application: The current study's results suggest that future research may be required to determine whether longer familiarization trials of pre-exercise HR palpation are needed to ensure greater accuracy in palpating step test recovery HR. Also, it may be essential to assess if the post 3 minutes step test palpated HR in the seated recovery position would contribute to an estimated

which would be closer to a subject's actual

as obtained via a maximal treadmill GXT. For if this scenario was to occur, it could alter how future step tests are implemented in strength and conditioning facilities.

Saturday, July 12, 2014, 10:15 AM–10:30 AM

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8. Effects of a 12-Week Balance and Fall Prevention Program for Older Adults on Measures of Functional Fitness

S. Paulson,1 D. Lentz,2 and M. Gray3

1Shippensburg University; 2Results Therapy & Fitness; and 3University of Arkansas

Purpose: The purpose of this study was to determine the effects of a 12-week balance and fall prevention program on selected measures of functional fitness (FF) among community-dwelling older adults. Methods: Nineteen older adults (M ± SD: age = 74.1 ± 6.5 years, mass = 74.7 ± 12.4 kg, height = 164.0 ± 8.7 cm) volunteered to participate in a 12-week balance and fall prevention exercise program. All subjects were free from uncontrolled cardiovascular, metabolic, and pulmonary disease. Anthropometric measurements and selected measures of FF were obtained before and after the exercise program. The following FF tests were completed: power stair climb (PSC), habitual 20-m walking speed (HW), 30-second chair stand (CS), 8-foot up-and-go (UPGO), and bilateral single leg static balance (SLR and SLL). Power from the PSC test was normalized using body mass (W/kg). Data were analyzed using repeated measures ANOVA. Results: All dependent variables significantly improved over the course of the 12-week program (p < 0.01). Relative power and HW speed increased by 48.3 and 14.9%, respectively. SLR and SLL static balance improved by 32.7 and 61.1%. The CS increased by 38.1% and UPGO improved by 27.1%. Conclusions: Participation in a 12-week balance and fall prevention program significantly improved all measures of functional fitness in community-dwelling older adults. Practical Application: It is imperative for older adults to participate in exercise programs geared toward enhancing quality of life and decreasing their fall risk by improving muscular power and functional ability. The older adults, within the present study, improved their functional fitness and walked significantly faster suggesting a decrease in fall risk.

Saturday, July 12, 2014, 10:45 AM–11:00 AM

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10. An Analysis of Perceptions of the Effectiveness of Creatine and Use at NCAA BCS vs. Non-BCS Schools

L. Judge,1 D. Bellar,2 J. Petersen,3 B. Craig,4 K. Holzclaw,4 N. LeBlanc,2 and O. Hindawi5

1Ball State University/School of PE, Sport, and Exercise Science, Muncie, IN; 2University of Louisiana at Lafayette; and 3Baylor University; 4Ball State University; and 5Hashemite University

Creatine has long been documented as an ergogenic aid for athletes who participate in sports emphasizing strength and power. Student-athletes may consume creatine without penalization as it is not a banned substance. However, the NCAA created a policy that prohibits universities from distributing creatine to student-athletes which may lead to negative consequences due to the universities inability to regulate the levels and quality of creatine consumption for student athletes. Purpose: This study analyzed baseline levels of creatine use and also allowed for further analysis of differences among factors related to creatine use based upon athletic conference affiliation. Methods: A 36-item online survey instrument was developed and distributed to NCAA Division I track and field coaches to collect data regarding creatine usage patterns. The participants (19.9 ± 1.30 years) were males (n = 137) and females (n = 123) who participated in resistance training to enhance athletic performance in collegiate field events. The experience, in years, of resistance training was 5.5 ± 0.90 for males and 3.6 ± 0.94 for females. Results: Overall results indicate that creatine continues to be utilized as a supplement (32.7%) among track and field athletes with significantly higher levels of use among BCS conference athletes (44.6%) than non-BCS conference athletes (28.8%), χ2 = 5.505, p = 0.019. The most common reasons for using creatine focused upon performance improvement in the following areas: strength (83.3%), recovery time (69.0%), and sport performance (60.7%). Additionally, 55.6% of these student-athletes indicated a desire for education and training regarding creatine use with significantly higher levels of interest from BCS athletes (65.6%) than non-BCS athletes (52.2%), χ2 = 6.425, p = 0.039. While the access to full-time nutritionist is available at 57.3% of the schools, there is a significant difference (χ2 = 9.096, p = 0.003) between BCS schools (73.7%) and non-BCS schools (51.7%). Conclusions: Despite the NCAA policy, many student-athletes continue to use creatine on an independent basis to improve performance and want to learn more about the supplement and its proper use and contraindications. Practical Application: Student-athlete concerns regarding potential side-effects and impurity of nutritional supplements warrant purposeful decisions by university athletic departments as well as the NCAA to provide additional creatine education and supervision.

Saturday, July 12, 2014, 11:00 AM–11:15 AM.

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11. G-Force Measurements During the 40 Yard Dash: The Reliability of a Commercial Accelerometer Unit

N. Moodie,1 M. Schieber,1 and D. Wassom2

1Rockhurst University; and 2Dynamic Athletics Research Institute

Accelerometers are a tool that are commonly used to objectively measure frequency, duration, and intensity of physical activity or exercise. An easily accessible tool such as an accelerometer could be beneficial to a widespread range of athletes, including athletes focused on improving speed and power. Purpose: This aim of the present study was to test the reliability of designated G-force measures obtained by a commercial accelerometer during the 40 yard dash. Methods: Twenty-eight competitive athletes volunteered to attend 2 anaerobic testing sessions on 2 nonconsecutive days. At the beginning of each session, athletes completed a required warm-up consisting of a 5 minutes jog, stretching of major muscle groups, and 2 progressive 50 yard sprints. After the warm-up, the accelerometer was placed on the athletes' back between the shoulder blades and anchored at 2 points with adhesive. Athletes then completed two 40 yard dashes with a 5 minutes rest interval between trials. Results: Data from the accelerometer unit was analyzed using software created by the unit developer. Based on the G-forces recorded by the accelerometer unit, the software created explosion, right-left symmetry, efficiency, and propulsion scores. Paired samples t-tests were used to examine differences in these scores for 40 yard dash scores within and between testing sessions. These tests determined no significant differences between trial 1-trial 2 scores within a testing session for explosion [t(27) = 1.04, p ≤ 0.05], right-left symmetry t(27) = −0.659, p ≤ 0.05], efficiency [t(27) = −1.71, p ≤ 0.05], and propulsion [t(27) = −1.08, p ≤ 0.05]. Similarly, no significant differences were found between test day 1 and test day 2 scores for explosion [t(12) = −0.484, p ≤ 0.05], right-left symmetry [t(12) = −1.31, p ≤ 0.05], and efficiency [t(12) = 0.79, p ≤ 0.05]. There was a significant difference between test day 1 and test day 2 scores for propulsion [t(12) = 2.40, p > 0.05]. Conclusions: The lack of significant differences for within and between testing sessions measures of explosion, symmetry, efficiency, and propulsion show that this accelerometer is a useful tool for examining G-forces. Times for the 40 yard dash trials for each testing session may have provided an explanation for differences in propulsion measures. Practical Application: A reliable tool such as this accelerometer can provide useful information regarding force production throughout a testing session, or throughout a training or rehabilitation program. Future research will examine trends in 40 yard dash times and measures of explosion, symmetry, efficiency, and propulsion. Acknowledgments: D.J. Wassom is employed by the company that produces the device tested in this study.

Saturday, July 12, 2014, 11:15 AM–11:30 AM

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12. Reliability of the Rate of Force Development During Countermovment Vertical Jump Performance

G. Haff,1 R. Ruben,2 J. Tufano,1 J. Conlon,1 and S. Laurent1

1Edith Cowan University; and 2Mountain River Physical Therapy

Purpose: This study was designed to examine the reliability of various methods for evaluating the rate of force development (RFD) during countermovement vertical jumps. Methods: Seventeen recreationally trained males (age = 22.8 ± 2.4 years; height = 1.81 ± 0.07 m; weight = 82.6 ± 9.5 kg; body fat = 13 ± 4.6%; jump height = 0.49 ± 0.04 m) were recruited for participation in the present study. Each subject was required to perform 5 countermovement vertical jumps on a force platform while holding a PVC pipe, which was attached to 2 linear position transducers. All samples were collected at 1000 Hz and were filtered using a fourth Order Butterworth low-pass filter at 100 Hz and then analyzed for several different force-time curve variables. The eccentric average RFD (EaRFD) was determined from the initial change in velocity to the minimum displacement (i.e., zero velocity) and the total average RFD (TaRFD) was taken from the minimum force to the maximum force. The peak RFD was determined with the use of 5 ms sampling windows during the eccentric portion of the force-time curve (EpRFD) and for the total curve (TpRFD). The absolute peak force was also assessed (PF) along with the jump height (JH). Reliability was assessed with the use of the coefficient of variance (CV%) and the intraclass correlation (ICC) and 90% confident intervals (90% CI). Acceptable reliability was determined as ICC > 0.70 and CV% < 15%. Paired comparisons were then performed to determine if differences existed between the various RFD measures. Pearson's product moment correlations were then used to correlate the JH performance with the various RFD measures and the PF measurement. Results: The EaRFD met the reliability requirement for the ICC = 0.93 (90% CI = 0.87–0.96) but only approached an acceptable reliability for the CV% (CV% = 15.0; 90% CI = 12.8–18.2). Similarly, the TaRFD had an ICC = 0.92 (90% CI = 87–96) and a CV% = 16.8 (90% CI = 14.3–20.4). The EpRFD exhibited acceptable reliability based upon an ICC = 0.79 (90%CI = 0.67–0.89), but failed to meet the CV% criteria (CV = 22.6%, 90%IC = 19.3–27.6). Similarly the TpRFD demonstrated an ICC = 0.79 (90% CI = 0.67–0.89) and a CV% = 22.4 (90% CI = 19.0–27.3). There was no statistical difference (p = 0.28) between the EaRFD (4469.6 ± 1948.8 n/s) and the TaRFD (4339.8 ± 2067.8 n/s). Additionally, there was no statistical (p = 0.20) difference between the EpRFD (12,091.9 ± 5532.0 n/s) and the TpRFD (12,144.3 ± 5490.9 n/s). The EpRFD (p = 0.02, r = 0.55), EaRFD, (p = 0.04, r = 0.50), TpRFD (p = 0.02, r = 0.055) were all significantly correlated with JH. The PF variable met both criteria for reliability (CV% = 2.9%, 90%CI = 2.5–3.5; ICC = 0.97, 90%CI = 0.95–0.98). PF was also significantly correlated (p = 0.01; r = 0.60) with JH. Conclusions: The method used to evaluate the RFD affects the measures reliability. The EaRFD method appeared to have the highest reliability for all the RFD methods evaluated in this study. Practical Application: When evaluating the RFD strength and conditioning professionals should use the EaRFD measure as it offers the most reliable approach and explains 25% of the variance in jump height. Additionally, the PF achieved during the countermovement vertical jump is also of importance as it explains 36% of the variance in jumping performance.

Saturday Poster Presentations

July 12, 2014, 11:30 AM–1:00 PM

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1. Comparison of Upper-Body Pushing and Pulling Strengths in College Wrestlers

D. Mayhew,1 C. Schmitz,1 B. Eagen,2 J. Arabas,1 and D. Schutter1

1Truman State University; and 2A. T. Still University of Health Sciences

There appears to be some controversy regarding the ratio of upper-body pushing strength to pulling strength. While some studies have found the push:pull ratio (PPR) to be approximately 1.00, other studies have noted significantly lower values in college wrestlers. Additional investigation seemed warranted to assess the accuracy of the PPR in athletes whose dominant training and competition involves the upper body. Purpose: The aim of this study was to compare upper-body pushing and pulling strengths in antagonistic movements in NCAA Division II wrestlers. Methods: Twenty-four wrestlers (age = 21.4 ± 1.2 years, height = 176.0 ± 10.8 cm, body mass = 78.8 ± 10.8 kg, %fat = 11.8 ± 3.6%) were measured for 1RM bench press (BP) and pull-up (PU). BP was assessing using the standard “touch-and-go” technique. PU was evaluated by attaching additional weight to the body via suspension from a belt secured around the waist until only 1 repetition could be completed. Prior to performance testing, each athlete underwent familiarization sessions with each lift. Subjects achieved 1RM in each exercise within 3–5 attempts. Each test was performed on a separate day in the pre-season prior to significant weight-reduction procedures. Results: BP (115.5 ± 24.1 kg) was not significantly greater (p = ??) than PU (110.4 ± 13.6 kg), and the 2 lifts were highly correlated (r = 0.75, p < 0.001). PPR (PPR = BP/PU × 100) was 104.3 ± 15.3%, which was not significantly different from 100% (p = 0.18). Body mass was significantly related to BP (r = 0.55) and PU (r = 0.66) but nonsignificantly related to PPR (r = 0.19, p = 0.38). Standardized regression coefficients indicated that BP contributed substantially more (78%) to explaining the variance in PPR than did PU (28%). When the top one-third of PPR athletes (n = 8, >110.2%) were compared with the bottom one-third (n = 7, <95.7%), BP values for the former (134.7 ± 22.1 kg) were significantly greater (p > 0.001) than for the latter (93.5 ± 14.2 kg) while PU values were not (110.2 ± 15.2 vs. 105.2 ± 11.6 kg, respectively). This remained the case when body mass was hold constant via ANCOVA. Conclusions: When pushing and pulling strengths are compared using exercises performed in different biomechanical planes in wrestlers, average pulling strength may be similar to average pushing strength. The balance in agonist and antagonist shoulder strengths may be due to the greater emphasis on bench press resistance training for pushing strength and on pulling maneuvers during the sport participation. Practical Application: Previous investigations using various methods of measurement for each maneuver suggests that the procedure used to assess pulling strength may have an impact of the value for PPR. The lack of muscle imbalance in the upper body of most wrestlers may offer some degree of protect against shoulder injuries.

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2. Test-Retest Reliability of panoramic Ultrasound Imaging to Examine Muscle Size and Quality of the Leg Extensor Muscles

T. Palmer,1 K. Akehi,2 D. Smith,1 and B. Thompson3

1Oklahoma State University; 2University of Nebraska at Kearney; and 3Texas Tech University

There has been a recent interest in the use of panoramic ultrasound (US) imaging for assessing the size (cross-sectional area; CSA) and quality (echo intensity; EI) of the leg extensor muscles. As a result, it may be of value to examine the reliability of panoramic US imaging of the leg extensors so that future studies can determine the minimum sample sizes necessary for observing real differences with adequate statistical power. Purpose: To determine the test-retest reliability for CSA and EI of the leg extensor muscles using panoramic US imaging. Methods: Ten men (mean ± SD, age = 23 ± 3 year; mass = 80 ± 8 kg; and height = 176 ± 6 cm) and 10 women (23 ± 5 year; 59 ± 7 kg; 163 ± 6 cm) volunteered for this investigation. Participants visited the laboratory 2 times, separated by 2–7 days at approximately the same time of day (±2 hour). During each visit, a single US image was obtained of the rectus femoris (RF) and of the vastus lateralis (VL) muscles using a portable B-mode US imaging device and linear-array probe. For the RF measurements, participants laid supine with the knees resting comfortably in extension near the natural resting position of 10°. For the VL measurements, participants laid on their left side with the knees resting comfortably in the same 10° position used for the RF assessments. All US images were taken in the transverse plane on the right leg using a panoramic US imaging technique, which consisted of the primary investigator moving the probe manually at a slow and continuous rate along the surface of the skin from the medial to lateral sides of the muscle. An adjustable, custom-made device that was fitted over each participant's right thigh was used during each assessment to assist with keeping the probe perpendicular to the skin, and a generous amount of water-soluble transmission gel was applied to both the probe and the skin to enhance acoustic coupling. Analyses of all US images were performed using Image-J software. The intraclass correlation coefficient (ICC, model 2,1), standard error of measurement (SEM), SEM expressed as a percentage of the mean (SEM%), minimal difference (MD) needed to be considered real, and MD expressed as a percentage of the mean (MD%) were calculated across visits to assess reliability for CSA and EI of the RF and VL muscles. Systematic variability in CSA and EI for each muscle was examined using separate one-way repeated measures analyses of variance (ANOVAs). Results: The reliability statistics for CSA and EI of the RF and VL muscles are presented in Table 1. Conclusions: The ANOVA results indicated no systematic variability in CSA and EI across visits (p > 0.05). ICC values were high, ranging between 0.811–0.979 and SEM% values were low, ranging between 3.636–4.409%. MD% values ranged between 10.078–12.221%. Practical Application: These findings demonstrate that panoramic US imaging may be a reliable assessment technique for measuring CSA and EI of the leg extensor muscles.

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3. Heart Rate Variability Responses to First Day of Spring Season Strength and Conditioning in Female Collegiate Soccer Players

A. Flatt and M. Esco

Auburn University at Montgomery

Purpose: This study aimed to determine if resting heart rate variability (HRV) values reflect previous day training load in a team of collegiate female soccer players after the first day of spring season strength and conditioning (S&C) training. Methods: A team of female collegiate soccer players (n = 11; height = 165.16 ± 5.82 cm; weight = 60.26 ± 6.30 kg; body fat = 27.07 ± 5.39%;

= 46.76 ± 2.40 ml·kg−1·min−1) volunteered for this study. Supine and standing HRV values were acquired from each participant with a specialized smart phone application that utilized a wireless ECG receiver and a chest-strap transmitter. Supine and standing measures were obtained following waking and bladder emptying on the first day of spring S&C training (SUPRE and STPRE, respectively) and on the 2 days that followed (SUPOST1, STPOST1, respectively and SUPOST2, STPOST2, respectively). The natural log transformed root mean square of successive normal-to-normal interval differences multiplied by 20 (lnRMSSDx20) was the HRV parameter evaluated in this study. This value was automatically determined by the smart-phone application following a 55-sec recording which was manually exported to the investigator for analysis via e-mail. A one-way repeated measures analysis of variance (ANOVA) procedure with Tukey Post-hoc follow up tests were used to determine if there was any significant differences across the 3 days in lnRMSSDx20. Results: The mean supine lnRMSSDx20 values for SUPRE, SUPOST1, SUPOST2 were 92.68 ± 8.19, 90.07 ± 7.58 and 90.62 ± 10.52, respectively. The supine values were not significantly different (p > 0.05). The mean standing lnRMSSDx20 values for STPRE, STPOST1, STPOST2 were 71.73 ± 10.07, 66.85 ± 10.10 and 70.78 ± 11.41, respectively. STPRE and STPOST2 were significantly higher compared to STPOST1 (p ≤ 0.05). Conclusions: The results of this study show changes in mean standing lnRMSSDx20 following a heavy training day in collegiate female soccer players. However, there were no significant mean differences in the supine HRV values across the 3 days. Therefore, standing HRV measures may better reflect recovery status following a day of heavy training compared to HRV measured in the supine position. Future work should assess whether HRV measures can reflect training load over a longitudinal training program. Practical Application: Advancements in technology have made for more affordable and convenient tools for acquiring HRV data in the field for the purposes of monitoring fatigue and training status in athletes. Though HRV has been traditionally measured in a supine position, this data suggests that a standing position may be a more sensitive marker in response to heavy training load in female team-sport athletes. It should be noted that while mean HRV values provide the coach with a general indication of recovery status of the team, individual assessment should also be considered.

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4. Self-Directed Learning in Ultra-Endurance Obstacle Course Racers

T. Piper,1 C. McMillan,2 C. Riley,2 A. Pearson,2 and D. Bellar3

1Western Illinois University, Department of Kinesiology, Major of Exercise Science; 2Western Illinois University; and 3University of Louisiana at Lafayette

Ultra-endurance races engage an individual in various activities consisting of muscular strength, muscular endurance, power, agility and cardiovascular endurance over an extended period of time. The preparation participants undertake for such events remains poorly understood. Self-directed learning is a construct that has been virtually ignored in the field of exercise science. Purpose: The purpose of this study was to determine the level of self-directed learning (SDL) present in ultra-endurance participants. Methods: Twenty-two participants (mean ± SD age, 31.9 ± 8.66 years, age range 19–58, 15 males, 7 females) enlisted in a 36 hours ultra-endurance obstacle course event volunteered to complete a SDL survey. All but one of the participants either held a college degree or was currently enrolled in college. Reported average physical training pre-event ranged from 60–90 minutes for 3 sessions per week. After The SDL survey that was utilized was the Self-directed learning readiness scale (SDLRS) and was administered to participants 1 hour prior to the event. Upon completion of the SDLRS average scores were compared to established criteria set by prior SDLRS validation research to determine the overall SDL levels of participants. SDLRS scoring levels include: low 58–176; below average 177–201; average 202–226; above average 227–251; high 252–290. Results: The SDLRS scores for participants ranged from 162 to 278. The mean score (mean ± SD: 234.14 ± 28.38) indicate an above average level of SDL. Conclusions: This investigation suggests that those that participate in ultra-endurance obstacle races tend to be above average self-directed learners. Considering the level of SDL present in these participants it would appear that these are individuals who take control of their individual training goals and are purposeful in their learning. Practical Application: This research investigated a poorly investigated population of athletes known for engaging in high intensity, long duration forms of exercise. Considering the level of SDL present in these participants it is clear that these are individuals who are autonomous learners. There is currently no SDL survey instrument that is specific to learning for exercise endeavors but, the SDLRS results from this study indicate that these participants have high degrees of general SDL tendencies. These tendencies likely carry over into SDL specific to ultra-endurance event training. This study may act as a guide for future research for further investigation into the area of self-directed learning and exercisers engaged in extreme or ultra-endurance events.

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5. An Examination of the Impact of Age and Experience on Stretching Practices of Collegiate Athletic Trainers in the United States

J. Popp,1 L. Judge,1 D. Bellar,2 L. Marcus,2 B. Craig,1 and E. Wanless1

1Ball State University; and 2University of Louisiana at Lafayette

Research pertaining to pre-activity warm-up and stretching and post-activity stretching has evolved over the past few decades. Purpose: The purpose of this study was to investigate the knowledge and practices of collegiate certified athletic trainers (ATs) to determine if stretching practices that are utilized align with the current research. Methods: A 101-item survey instrument was developed and used to collect data. A total of 500 participants (17.6%; 252 male, 248 female) completed the survey. A large number of ATs (82.5%, n = 430) who responded to this survey held at least a master's degree or above, with the graduate program being athletic training (20%, n = 100), exercise science (22.4%, n = 112), or another related field (19.8%, n = 99). Of the 500 participants, 59 reported holding the CSCS credential. The questionnaire was designed to gather demographic, professional, and educational information, as well as specific usage of pre- and post-stretching by AT's. Subsequently, items of interest were analyzed for differences by key demographic variables (i.e., age and experience) and applicable frequency counts were compared statistically via Pearson's chi-square and Kruskal–Wallis analysis in order to assess potential differences. Significance was set at a priori to alpha <0.05, and all statistical analyses were performed using SPSS version 20.0. Results: Analysis of the impact of age and number of years of experience of the full time AT yielded a number of interesting findings regarding pre- and post-activity stretching practices. ATs reported that only 28.0% of athletes under their care are performing dynamic stretching exclusively prior to activity. A higher percentage of younger AT's reported using pre-activity proprioceptive neuromuscular facilitation (PNF) stretching (χ2 = 11.982. p = 0.035). Of those 40 years and under, 19% (n = 57) reported PNF was recommended for pre-activity stretching, whereas in ATs over 40, only 7% (n = 7) recommended PNF for pre-activity stretching. This study also found that those aged 26–40 years recommended static stretching more post-exercise (χ2 = 18.2, p ≤ 0.05) as well as those with 1–15 years of experience as an AT (χ2 = 12.8, p ≤ 0.05) than those who are older and more experienced. Conclusions: The results of this study indicate that age and experience may influence how well research guidelines are followed. Older AT's reported a much better understanding about the appropriate place for PNF stretching. Further research is needed to delineate how these factors affect decisions. Practical Application: The results of this study demonstrate the necessity for some ATs to re-evaluate their methods, perhaps aligning them with the existing research.

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6. Electromyographic Comparison of Superficial Musculature During Varying Suspension Training Devices

R. Snarr1 and M. Esco2

1Arizona State University; and 2Auburn University at Montgomery

Purpose: The purpose of this investigation was to compare the electromyographical (EMG) activity of the pectoralis major (PM), anterior deltoid (AD), triceps brachii (TB), and rectus abdominis (RA) while performing push-ups on a single- (SAS) vs. a dual-anchoring (DAS) suspension device. Methods: Ten apparently healthy men (n = 5, age = 25.4 ± 3.78 years, weight = 84.82 ± 8.39 kg, height = 180.85 ± 10.98 cm) and women (n = 5, age = 22.5 ± 2.12 years, weight = 63.64 ± 3.21 kg, height = 165.1 ± 3.59 cm) volunteered to participate in this study. The participants were instructed to perform 5 repetitions of a modified push-up on 2 suspension devices with different attachment points (i.e., SAS and DAS). Mean peak (raw) electromyographical activity of the PM, AD, TB, and RA were recorded for each participant when performing the 2 exercises. Results: The mean peak EMG activity during push-ups with the SAS was 2.32 ± 0.42 mV for the PM, 5.34 ± 3.55 mV for the AD, 5.73 ± 1.43 mV for the TB, and 0.95 ± 0.17 mV for the RA. The mean peak EMG activity during push-ups with the DAS was 2.57 ± 0.31 for PM, 5.17 ± 1.94 for AD, 4.38 ± 1.88 for TB, and 0.89 ± 0.29 for RA. The only significant difference between the SAS and DAS push-ups was with TB (p ≤ 0.05). Conclusions: This investigation demonstrated significantly greater EMG activity of the TB during push-ups performed on the single-anchor suspension training device as compared to the dual-anchoring system. This finding could be due to a greater range of motion of the ulnohumeral joint when performing push-ups with an SAS compared to a DAS device. All other superficial musculature tested (i.e., PM, AD, and RA) showed no significant differences between the 2 training systems. Practical Application: The results of the study indicate that with a SAS device, the triceps brachii may be activated to a greater extent when performing a suspension push-up compared to using a DAS system. Therefore, single-anchoring suspension devices may be more suitable for targeting the TB compared to dual-anchoring systems when performing suspension push-ups.

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7. The Relationship Between Visual Skills and Batting Performance of Professional Baseball Players

F. Spaniol, A. Quinonez, S. Cochran, B. Hicks, M. Alves, and B. Warren

Texas A&M University–Corpus Christi

Purpose: The purpose of this study was to investigate the relationship between visual skills and batting performance of professional baseball players. Methods: Three hundred and fifty-two (352) professional baseball players were evaluated for visual skills and batting performance during the 2013 minor league baseball season. Visual skills were assessed using the Vizual Edge Performance Trainer (VEPT), a commercial software program designed to assess eye alignment, depth perception, convergence, divergence, visual recognition, and visual tracking. Individual subtest scores were used to generate a composite VEPT score. All visual skills testing was conducted by professional baseball scouts as part of pre-draft player evaluations. Batting performance was determined by 2013 season statistics, which included batting average (BA), bases on balls percentage (BB%), strikeout percentage (SO%), on base percentage (OBP), slugging percentage (SLG), and on base plus slugging (OPS). Results: Descriptive statistics were used to analyze player performance based on visual skills. Players were divided into quartiles based on their comprehensive VEPT score. Batting performance was then compared for the upper and lower VEPT quartiles. Statistical analysis indicated significant differences for BA (0.268–0.253), SO% (0.216–0.248), OBP (0.334–0.283), and OPS (0.713–0.667). When comparing the upper and lower 10% of VEPT scores, even greater disparities were found for BA (0.272–0.250), SO% (0.226–0.260), and SLG (0.398–0.381). In addition, the upper quartile in BA had significantly better visual recognition response time (0.97 seconds–1.08 seconds) when compared to the lower quartile. Practical Application: The results of this study provides evidence that superior visual skills are indicative of superior batting performance in several statistical categories including BA, SO%, OBP, and OPS. Since visual skills appear to play a significant role in batting performance, coaches, trainers, and administrators may consider using programs such as VEPT to assess baseball players.

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8. Does Citrulline Malate Ingestion Augment Muscular Performance During a Selected Lower-Body Training Protocol

B. Wax1 and S. Dorgo2

1Mississippi State University; and 2University of Texas at El Paso

Ergogenics are intended to improve athletic performance for training and competitive purposes. An amino acid combination of L-citrulline and malate is claimed to provide an ergogenic effect on muscular performance during resistance training performance. However, limited data exist to support these claims. Purpose: To investigate the ergogenic effects of citrulline malate (CM) during a hypertrophy-type lower-body resistance training protocol. Methods: Fifteen resistance trained males (mean ± SD age: 21.8 ± 0.9 years, mass: 87.1 ± 10.4 kg, height: 179.6 ± 9.4 cm, BMI = 27.0 ± 2.3 kg/m²) participated in a randomized, counterbalanced, double blind study. Subjects were randomly assigned to CM (8.0 g) or placebo (PL) and performed 8 sets of hack squats at 67% of their one-repetition maximum, with 90 seconds recovery periods to volitional failure. One week later, subjects ingested the other supplement (CM or PL) and performed an identical exercise protocol. Blood lactate measures were obtained pre- and immediately post-exercise. Blood pressure and heart rate measures were obtained at rest (pre-), and 5- and 10-minute during the post-exercise period. Rate of perceived exertion (RPE) was surveyed after the last set and rated muscle soreness data were collected 24- and 48-hours post-training. Results: CM supplementation resulted in significantly lower heart rate levels 5-minute (p = 0.004) and 10-minute (p = 0.031) post-exercise, and lower systolic (p < 0.001) and diastolic (p = 0.010) blood pressure 5-minute post-exercise, Also, subjects performed significantly more repetitions in 5 out of 8 sets when on CM supplementation (p < 0.034), and completed a significantly higher total volume of training (p = 0.035) compared to placebo. Furthermore, subjects reported significantly lower levels of muscle soreness 24-hours (p = 0.001) and 48-hours (p < 0.001) post-training when receiving CM supplementation. However, no significant group differences were observed for post-exercise blood lactate levels (p = 0.443) and RPE ratings at set 8 (p = 0.097). Conclusions: Collectively, these novel findings suggest that CM increases muscular performance during a lower-body hypertrophy resistance protocol. Positive effects of CM are particularly noted through higher workload performance at similar lactate and RPE levels, and the more rapid recovery of the cardiovascular system immediately after exercise. Competitive athletes may also benefit from lower levels reported of muscle soreness following intensive resistance training sessions when taking CM supplementation. Practical Applications: Our data suggest that acute CM ingestion prior to lower-body resistance exercise may provide an ergogenic effect by increasing muscular performance and potential mitigating demands on the cardiovascular system, yet further research is warranted To explore the acute and chronic effects of CM supplementation.

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9. Increasing the Flexibility of the Pectoralis Minor: Effectiveness of a Foam Roller Stretch

D. Witt, L. Mulligan, N. Talbott, A. Higgins, and M. Duffy

University of Cincinnati

Purpose: Stretching of the pectoralis minor (PM) is frequently a part of conditioning programs to prevent shoulder pain and to optimize performance. Because tightness of the PM has been shown to change the position of the scapula during overhead motions such as throwing or lifting, maintaining PM flexibility is important for normal shoulder biomechanics. Multiple methods have been suggested to stretch the PM including doorway stretches and corner stretches, however sustained increases in the PM flexibility after these stretches are questionable. Another suggested method for stretching the PM involves the use of a foam roller. Lying on the foam roller with the shoulders in horizontal abduction and the trunk stabilized, gravity, along with the weight of the arms, are used to apply a traction force between the attachments of the PM thereby increasing PM flexibility. The purpose of this study was to determine (a) if this common stretch immediately altered PM flexibility; and (b) if any change in PM flexibility was maintained 1 week after the stretch. Methods: Initial PM length was recorded using 3 methods: measurement from the table to the acromion with the elbow extended (method 1); measurement from the table to the acromion with the elbow flexed (method 2) and measurement from the coracoid to the fourth rib (method 3). Subjects were then randomly assigned to either a stretch or a no stretch group. Subjects in the stretch group were positioned supine on a half foam roller with a 7 cm radius. The stretch was maintained for 1 minute. Subjects in the no stretch group sat quietly in a chair. Immediately after the stretches, the PM length was re-measured using all methods. The measurements were repeated 1 week later. Results: PM lengths were not significantly greater following the stretch. Pretesting PM length values for individuals who performed the stretch using Method 1, Method 2 and Method 3 were 5.12, 4.31 and 17.51 cm respectively. Following the stretch, values were 4.96, 4.19 and 17.72 cm respectively. One week following the stretch, PM length was significantly less than the original PM lengths recorded using Method 1 and Method 2, with length values changing by over 0.3 cm when compared to the initial length. Conclusions: A supine stretch using a foam roller did not significantly increase PM length. Practical Application: Flexibility of the PM was not increased with a 1 minute stretch using a foam roller. Increasing the time of the stretch may be needed to produce a significant change. In addition, additional methods of assessing PM length may be needed as it is conceivable that flexibility did increase after stretching but common PM length measurement tests were not adequate to detect changes.

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10. Leukocyte IGF-1 Receptor Expression During Muscle Recovery

M. Fragala,1 A. Jajtner,2 J. Townsend,1 A. Gonzalez,2 A. Wells,2 L. Oliveira,2 J. Hoffman,2 J. Stout,2 and D. Fukuda2

1University of Central FL; and 2UCF

Insulin-like growth factor 1 (IGF-1) is an anabolic growth factor important for muscle recovery. Recently, a regulatory role of IGF-1 in the immune response for muscle repair has been suggested, but how it modulates the inflammatory process is largely unknown. Purpose: We evaluated changes in leukocyte expression of IGF-1 receptors (IGF-1R) during recovery from resistance exercise with and without cold water immersion (CWI) treatment to determine if changes in the potential for IGF-1 interactions with specific immune cells may mediate the role of IGF-1 in muscle repair. Methods: Twenty resistance trained men (aged 18 to 35 years) performed heavy resistance exercise followed by cold water immersion (CWI) or control treatment (CON) on 3 consecutive days. Blood was sampled at baseline (PRE), immediately post (IP), 30-minutes post (30P), 24 hours post (24P), and 48 hours post (48P) exercise. Circulating IGF-1 was assayed and IGF-1R expression (CD221) on gated circulating leukocytes was measured by flow cytometry. Time and treatment effects were analyzed with ANCOVA. Results: Circulating IGF-1 significantly increased from PRE to IP as a result of the exercise, but no differences between CON and CWI were observed. Mean Fluorescence Intensity (MFI) of CD221 on monocytes and granulocytes and percent of CD221 + monocytes significantly increased at 30P (p < 0.000) and returned to pre-exercise levels by 24H. No treatment effects on monocytes or granulocytes were observed. However, on lymphocytes, MFI of CD221 + significantly increased from PRE to 30P in CWI only, but not CON. Conclusions: Resistance exercise appears to increase IGF-1R expression on monocytes and granulocytes, suggesting that IGF-1 likely mediates their role in the earlier stages of muscle recovery. In addition, CWI appears to alter IGF-mediated responses on slower-acting lymphocytes, suggesting that its effects may be seen in the later stages of muscle repair. Practical Application: Changes in IGF-1 and it receptor expression on leukocytes appear to be part of the mechanism that helps facilitate recovery from resistance training. Further research into the mechanisms underlying the interactions between the endocrine and immune systems is warranted. Acknowledgments: This research was supported by the NSCA Young Investigator Grant.

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11. Impact of Caffeine Ingestion on Circulating Growth Hormone and Insulin Like Growth Factor-1 Levels During Endurance Exercise

D. Heikkinen,1 R. Carmichael,2 and S. Herrick3

1Fitchburg State University; and 2Plymouth State University, 3Springfield College

Purpose: The purpose of this study was to investigate the acute effect of caffeine ingestion on serum growth hormone (GH), and insulin-like growth factor-1 (IGF-1) levels in healthy, recreationally active males during endurance cycling exercise. Methods: The subjects (N = 10) included healthy, recreationally active males (29.1 ± 5.4), height (179.35 ± 8.12), weight (85.10 ± 11.72), and

(51.62 ± 7.14). All subjects participated in 3 research sessions. The first session was used to determine the

of each subject, this value was used to determine an exercise intensity of between 60 and 70% of

for the repeated measures sessions. In the repeated measures sessions the subjects participated in stationary cycling exercise for duration of 45 minutes of time. Caffeine was administered in a double blind, placebo controlled design 60 min prior to the exercise task at a dose of 5 mgkg of bodyweight. Blood was collected 60 minutes pre-exercise, 0 minute pre-exercise, 0 minute post-exercise, and 30 minutes-post exercise in order to measure serum GH and IGF-1 levels. A 2 × 4 repeated measures analysis of variance (ANOVA) was calculated to compare the dependent variables across testing periods. Results: For GH no significant interaction (p = 0.83) was observed between the treatment and time. A significant main effect was observed for time (F = 15.738, p < 0.01). The overall mean levels of GH across time were 1.54 ng/ml (SD = 1.35) at 60 minutes pre exercise, 1.55 ng/ml (SD = 1.41) at 0 minute pre exercise, 10.72 ng/ml (SD = 8.17) at 0 minute post exercise, and 3.15 ng/ml (SD = 3.03) at 30 minutes post exercise. Significant differences for GH (p ≤ 0.05) existed in serum GH levels at 0 minute post exercise compared to the other time points. No significant main effect (p = 0.26) were observed for treatment. For IGF-1 no significant interaction (p = 0.39) was observed between the treatment and time. A significant main effect for the treatment was observed (p = 0.01). The overall mean levels of IGF-1 were 113.47 ng/ml (SD = 33.31) with caffeine, and 111.05 ng/ml (SD = 36.18) with placebo. No significant main effect (p = 0.67) for time was observed. Conclusions: In conclusion, caffeine ingestion prior to endurance cycling exercise did not have an effect on serum GH. An increase in serum IGF-1 was observed in the current study over time. Practical Application: These findings suggested that caffeine ingestion prior to endurance exercise does not have an impact on serum GH levels. An increase in serum IGF-1 levels was observed. Further studies may investigate possible fluctuations in serum GH and IGF-1 during endurance exercise with caffeine ingestion at varying exercise intensity levels and with different age demographics.

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14. Daily Variation in Hydration Levels of College Football Players During the Season

J. Humphrey, J. Arabas, and D. Mayhew

Truman State University

Maintaining hydration is a primary concern among athletes, coach, and athletic trainers. Despite efforts by coaches and athletic trainers, some athletes may not rehydrate sufficiently between practice sessions. Purpose: The purpose of the study was to determine the daily variation in the hydration level of college football players during the competitive season. Methods: Twenty-three NCAA Division II football players (age = 20.2 ± 1.5 years, height = 185.5 ± 5.9 cm, weight = 106.5 ± 22.4 kg) volunteered to provide urine samples upon rising in the morning (T1), prior to afternoon practice (T2), and after the practice (T3) on 2 days separated by a week. The environmental temperature and humidity were comparable on both days. All samples were allowed to equilibrate to room temperature before being measured for urine specific gravity (Usg) using a digital refractometer. Results: Reliability coefficients between days ranged from poor (T1, ICC = 0.417) to moderate (T1, ICC = 0.629) to strong (T3, ICC = 0.810). Comparison of the days produced no significant difference at each test period (p > 0.13), and hence the samples were averaged to represent each time period. A repeated measures ANOVA revealed that players had significantly higher Usg at T1 (1.024 ± 0.004 g/cc) and T3 (1.025 ± 0.007 g/cc) than at T2 (1.017 ± 0.006 g/cc). Using the 1.020 g/cc as the marker for athletic hydration, 83% of players could be considered dehydrated at T1. Prior to practice (T2), 30% of players were above the standard (dehydrated) and 32% of those had been dehydrated at the morning sampling. Following practice (T3), 78% of players were above the standard despite ad libitum water availability during the 2-hour practice. Six players (26%) were dehydrated at all 3 test periods. There was no significant difference (p > 0.18) between players on the traveling squad (n = 11) and those who were not (n = 12) at any test period, suggesting that practice repetitions were not a factor in the hydration pattern. Conclusions: Morning urine samples suggest that football players may not be fully rehydrated following a mid-week practice day, although pre-practice samples showed most players had returned to satisfactory hydration levels prior to practice. Despite available water during practice, many players may be dehydrated following a 2-hour session and should make a conscious effort to rehydrate before retiring for the night. Practical Application: Considering the importance of euhydration for adequate sports performance, the current data indicate that football players have to make a conscious effort to rehydrate between practice days. The most critical phase of the rehydration process may be the evening hours following a practice session.

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15. Difference in Body Density Among Women Athletes From Different Sports

N. Kline, J. Arabas, L. Jorn, and D. Mayhew

Truman State University

A vital issue in the health of female athletes is the integrity of the skeleton. Although not frequently measured, the density of the bone may be an important issue for athletes engaged in different sports. Purpose: The purpose of the study was to determine the regional and total bone densities among female college athletes. Methods: Seventy-five NCAA Division II women athletes (age = 20.1 ± 1.1 years, height = 169.4 ± 8.4 cm, weight = 69.0 ± 11.8 kg) from 6 sports volunteered to submit to dual X-ray absorptiometry (DXA) during various stages of a yearly training cycle. Regional lines were carefully adjusted to assess the bone density (BD) of arms, legs, torso, and pelvis. BMC was converted to total bone mineral (TBM). Groups were constructed by combining running sports (RS, soccer and softball, n = 21), jumping sports (JS, basketball and volleyball, n = 25), mixed sports (MS, track, n = 18), and support sports (SS, swimming, n = 11). Results: MANOVA revealed that JS were significantly taller than the other groups (p < 0.001), but none of the groups were significantly different in age, weight, fat mass, lean mass, or %fat. MANOVA for regional BD showed the groups were not significantly different for the arm (p = 0.10). Furthermore, SS and MS were not significantly different on trunk, rib, pelvis, and spine BD but were significantly lower than JS and RS on each. SS was significantly lower in leg BD than the other groups. JS had significantly greater TBM than RS, MS, and SS even when adjusted for body weight differences by ANCOVA. In addition, RS, MS, and SS did not differ significantly in TBM. Comparison with age-adjusted BD norms revealed that SS (Z = 0.37 ± 0.83) had significantly lower values than MS (1.61 ± 1.58), JS (1.92 ± 0.89), and RS (1.96 ± 1.01). Conclusions: Women swimmers have a lower BD and TBM than most other sports even when adjusted for body weight differences. This study supports previous work showing the effect of heavy loading on skeletal development of women and provides further evidence of the positive effect of power training on BD. Practical Application: Sports in which the majority of the training time is spent in a body weight supported environment do not appear to promote bone integrity in women despite the supplemental use of resistance training. The degree to which this may have long-term effects on the bone integrity of women athletes warrants further investigation.

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16. Relationship of Abdominal Circumference and Body Mass Index to Body Composition in Air Force Men and Women

G. Leahy,1 D. Friederich,1 T. Crowder,2 D. Mayhew,3 and A. Smith-Ryan4

1Davis-Monthan Air Force Base; 2United States Military Academy; 3Truman State University; and 4University of North Carolina

The United States Army, Navy, and Marines utilize a combination of Body Mass Index (BMI) and circumference-derived equations to determine body composition and health risk. The Air Force (AF) utilizes Abdominal Circumference (AC) measurements only. To date, no direct comparison of the AF method with BMI or body composition has been conducted. Purpose: The purpose of this study was to evaluate the accuracy of BMI and AC for identifying body composition in Air Force men and women. Methods: Air Force men (n = 436) and women (n = 153) were evaluated for body composition using air displacement plethysmography (BodPod). Abdominal circumference values were collected from physical fitness (PT) test results measured 2 cm above the iliac crest. Height and weight were used to calculate BMI (kg/m2). BMI groups were determined using the standard categories (underweight ≤18.5, normal = 18.6 to 24.9, overweight = 25.0 to 29.9, obese ≥30). Masked obesity was assessed as BMI < 25 when % fat was greater than the obesity level for men (≥20%) and women (≥30%). Results: Fat-free mass (FFM) did not change significantly across the age span for either men (r = 0.07) or women (r = 0.13). Age was significantly associated with increases in fat mass (FM) and %fat in men (r = 0.33 and 0.33, respectively) and women (r = 0.23 and 0.19, respectively). High BMI values correctly identified 56% of obese men (>20% fat) and 46% of obese women (>30% fat). 13% of men and 29% of women had masked obesity. FFM could be predicted with acceptable accuracy using 4 variables (FFM (kg) = 1.48 BMI +1.26 AC (cm)—2.83 AC (cm)/Height (m) + 10.35 Gender (0 = female, 1 = male) + 43.67, R = 0.86, SEE = 4.9 kg, CV = 7.7%). Body Mass Index and AC correlated comparably well with total body FM in men (r = 0.81 and 0.79, respectively) and women (r = 0.86 and 0.80, respectively). For AF men and women whose AC values would have resulted in an “excellent” score on the PT test, 41% of men and 43% of women had % fat indicative of obesity. Conclusions: The increase in body mass with age in Air Force men and women is more related to gains in FM than to changes in FFM. BMI predicts FM as well as AC. Practical Application: The high number of AF personnel with undesirable levels of body fat despite possessing “excellent” AC scores suggests the passing AC cutoff points for AF men and women of 99 and 90 cm, respectively, may be too lenient. If predicting total body fat is desired, BMI could be substituted for AC.

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17. The Effects of Hydration Status on Muscular Performance From Pre- to Post-Season in Female, Freshman, Soccer Players

D. Melrose, M. Alves, R. Bonnette, and F. Spaniol

Texas A&M University–Corpus Christi

Purpose: The purpose of this investigation was to examine differences in hydration status from pre-to post-season and differences in muscular performance from pre-to post-season in Division 1, female, freshman soccer players. Additionally, it was the purpose of this investigation to determine if relationships exist between hydration and performance values. Subjects: Seventeen female soccer players (age: 18.0 ± 0.0 years; height: 164 ± 5.35 cm; weight: 63.54 ± 8.23 kg; BMI: 24.0 ± 2.34 kg/m2), all members of a first year Division 1, start-up collegiate soccer program were used as subjects. Subjects were tested immediately prior to and after their competitive season. Methods: Body composition was measured using the BOD POD system (%FFM: 77.04 ± 4.05). Hydration values were obtained using the InBody 720 bioelectrical impedance system. Values obtained included: intracellular water (ICW), extracellular water (ECW), and total body water (TBW). Muscular performance factors were obtained using the Myotest Pro device. Twenty-four different muscular performance variables were obtained using this device. Using SPSS v.22, the following statistics were performed for all data: means ± SD's, paired t-tests, and correlations. The alpha level was set at 0.05 for all data analysis. Results: Analysis showed a significant decrease in hydration over the course of the season: ICW pre-post (22.73 ± 2.28 vs. 21.50 ± 2.26 kg, t(13) = 3.593, p = 0.003), ECW pre-post (13.09 ± 1.39 vs. 12.69 ± 1.26 kg, t(13) = 2.387, p = 0.033), TBW pre-post (35.32 ± 3.64 vs. 34.20 ± 3.49 kg, t(13) = 3.182, p = 0.007). The following performance factors showed significant differences from pre-to post-season; average bench press power (295.69 ± 57.09 vs. 326.46 ± 40.30 W, t(12) = -2.219, p = 0.047), maximum bench press power (327.92 ± 16.19 vs. 352.08 ± 7.58 W, t(12) = -2.629, p = 0.022), CMJ force (22.59 ± 1.97 vs. 21.54 ± 1.56 N/kg, t(13) = 2.352, p = 0.035) and jump plyometric height (7.58 ± 1.39 vs. 5.97 ± 1.74 cm, t(13) = 2.948, p = 0.011). As mentioned, pre-season ICW, ECW, and TBW was significantly greater than post-season. Pre-season correlational analysis showed moderate significant correlations for ICW and bench press max power (r = 0.518, r2 = 0.262, p = 0.040), ICW and CMJ force (r = − 0.487, r2 = 0.496, p = 0.047). ECW was also significantly correlated with CMJ Force (r = −0.562, r2 = 0.315, p = 0.019). TBW was significantly correlated with bench press max power (r = 0.498, r2 = 0.248, p = 0.050) and CMJ force (r = 0.519, r2 = 0.269, p = 0.033). Post-season ICW, ECW, and TBW was significantly less than pre-season values. Post-season correlational analysis showed moderate significant correlations for ICW and average bench press power (r = 0.575, r2 = 0.298, p = 0.040), bench press velocity (r = 0.589, r2 = 0.346, p = 0.034) and bench press maximum power (r = 0.609, r2 = 0.370, p = 0.027). ECW was significantly correlated with the plyometric reaction index (r = −0.573, r2 = 0.328, p = 0.032). TBW was significantly correlated with bench press velocity (r = 0.566, r2 = 0.322, p = 0.044) and bench press maximal power (r = 0.587, r2 = 0.344, p = 0.035). Conclusions: Within the scope of this investigation, college aged freshman women upper body power was shown to be moderately correlated with maximal bench press power, CMJ force and bench press velocity. The only performance value that decreased significantly from pre-to post-season as did hydration status was CMJ force. Practical Application: It is advisable to maintain proper hydration during the competitive season as hydration can suffer. In addition, coaches and athletic trainers should consistently teach and remind young players about proper hydration as it may negatively affect some aspects of performance.

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18. Concurrent Effects of Foam Rolling on Explosive Power and Flexibility

T. Keating and L. Sanchez

Manhattan College

Foam rollers FR have become increasingly popular among athletes as a recuperative and preparatory modality. While there is some data to support their use as the former, little evidence, as yet, supports the latter. If it can be demonstrated that use of FR acutely enhances flexibility while, at the least, preserving explosive power performance, it may be a worthwhile preparatory modality. Purpose: The purpose of this investigation was to determine the concurrent effects of FR on acute flexibility and explosive power performance. Methods: Sixteen Kinesiology students (10 M, 6 F; 20.7 ± 1.2 years) volunteered for participation in this pretest-posttest design. As previous research, involving static stretch, has often acutely found incompatibility of the 2 dependent measures (power and flexibility), a true control group was deemed unnecessary. After thorough orientation, subjects performed pretests PRE of vertical leap VL using a pressure switch timing system, followed by sit-and-reach SR measures (each, best of 3). VL was always performed first to minimize potential static stretch effects. In the same manner, posttests PST were performed after 2 minutes of slow (3–5 seconds per in), bilateral FR treatment for the hamstrings and quadriceps. A standard white (moderate density), cylindrical foam roller was used for all trials, subjects instructed to use increments of body weight to produce mild discomfort. Results: Dependent t tests revealed significant (p < 0.01) improvements in SR (10.75 ± 3.27 PRE vs. 12.25 ± 3.33 PST) as well as VL (20.99 ± 3.90 PRE vs. 21.79 ± 3.79 PST. Conclusions: It can be concluded that FR is an effective way to acutely enhance flexibility while preserving explosive power in college-age subjects. Practical Application: As an alternate pre-event modality to enhance flexibility without compromising explosiveness, FR may be substituted for more traditional training modes, though additional research is needed.

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19. Exercise Intervention on Performance Measures Related to Cardiovascular and Neuromuscular Health In HIV + Women Recovering From Substance Abuse

A. Fernandez, A. Duplanty, R. Budnar, H. Luk, D. Levitt, T. Layman, D. Hill, and J. Vingren

University of North TX

Purpose: To examine the combined effects of resistance and aerobic training on physical performance measures related to cardiovascular and neuromuscular health in HIV + women recovering from substance abuse. Methods: Sixteen HIV + women (41 ± 9 years, 164 ± 6 cm, 78.1 ± 17.1 kg, 36 ± 10% body fat) were recruited shortly after enrollment in an intensive 60-day in-patient substance addiction/abuse treatment program at a local treatment facility. Participants were randomly assigned to an exercise (supervised combined aerobic and resistance exercise sessions 3 times per week) or control (no exercise training) condition for a 6 week intervention period. For participants in the exercise group, each exercise session involved 1 hour of conventional resistance training and 0.5 hours of aerobic exercise and was conducted by experienced trainers. Before (Pre) and after (Post) the invention period, upper and lower body strength (maximal isometric bench press and squat) and cardiovascular endurance (Åstrand-Rhyming cycle ergometer test) were assessed. Results: In the exercise group maximal isometric squat strength (Pre 1673 ± 486; Post 2000 ± 607 N) increased significantly (p ≤ 0.05); whereas, no change was observed in the control group (Pre 1377 ± 358; Post 1381 ± 326 N). A significant difference between groups was found for %change (Δ) in absolute

from Pre to Post; absolute

increased by 14.0% in the exercise group and decreased by 9% in the control group. No adverse effects of the exercise intervention were observed. Conclusions: Combined aerobic and resistance training improved aspects of cardiovascular and neuromuscular health in HIV + women recovering from substance abuse without any adverse effects. Practical Application: A resistance and aerobic exercise training program should be included in the standard of care for in-patient substance abuse treatment for women living with HIV to improve the health and function of activities of daily living for this population.

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20. Clinician Level of Association Between Live and Video Visual Assessments of Foot Type

F. Gardin, J. Williams, S. Leigh, R. Horn, and D. Middlemas

Montclair State University

Feet may be classified as supinated (high arched), neutral, or pronated (flat footed). Foot typing is used to prescribe orthotics correctly to reduce injury risk. Visual appraisal is the most common clinical assessment of foot type, and is considered the gold-standard. Video observation to determine foot type is a promising method that may allow a clinician to make an assessment from a different location. This method may also benefit students by providing them with many opportunities to practice the skill by themselves. Agreement among live and video assessments has been unreliable. Purpose: The purpose of this study was to determine the agreement and correspondence between live and video observations of foot classification among 3 independent raters. Methods: Three certified athletic trainers with varying years of experience conducted the foot typing. All completed a training session in foot typing prior to this study. The participants were 31 male (15) and female (16) college students (22.48 ± 2.95 years) who reported no current injuries. All 31 participants were observed live, and the right foot of each participant was independently classified. All participants were then asked to walk on a treadmill and were video recorded at anterior-oblique, sagittal, posterior angles. Classification of the right foot was repeated using the video recordings after a gap of one month. Foot types were classified as supinator, neutral, or pronator, and coded as −1, 0, and 1 respectively. To assess agreement between the observation methods, the mean difference for each rater was calculated. To assess correspondence between the observation methods, Cramér's V for each rater was calculated. To assess overall agreement and inter-rater reliability between the observation methods, Weighted Cohen's Kappa was calculated. Results: The mean differences were −0.29, −0.06, and −0.10 for rater 1, rater 2, and rater 3, respectively. Cramér's V were φc = 0.42 (p = 0.03), φc = 0.86 (p < 0.01), and φc = 0.65 (p < 0.01) for rater 1, rater 2, and rater 3, respectively. Weighted Cohen's Kappa for the 2 observation methods was κ = 0.309. Conclusions: Agreement between the observation methods was different among raters. Raters 2 and 3 had an agreement between observation methods 3 times greater than rater 1, as shown by their smaller mean differences. Correspondence between the observation methods was also different among raters. Raters 2 and 3 also had greater correspondence between observation methods than rater 1, as shown by their greater Cramér's V. There were differences in ratings by experience, which may indicate an experience effect between methods. All raters tended towards classifying feet as more supinated when observing video, as shown by negative mean differences. This may be a treadmill effect, where the black belt caused the feet to look more supinated. Overall agreement between observation methods was fair, as shown by a Cohen's Kappa between 0.2 and 0.4. This suggests video observation is a somewhat reliable method for foot type classification. Practical Application: These data suggest that video observation may be useful to classify foot type. Investigation into the effects of experience and the appearance of the foot against the treadmill belt is warranted.

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21 Collegiate Football Players Concussion Assessment

B. Graves, J. Burnside, J. Kiddy, and A. Krahwinkel

Florida Atlantic University

Approximately 50% of individuals, who suffer a concussion, do not seek medical attention, according to the World Health Organization. With this much underreporting, a reliable rate of concussion incidences is difficult to obtain. Nearly 9% of high school and 6% of collegiate athletes have sustained at least one (Gessel, et al., 2007). With concussions being brought to the forefront of an athlete's health, the number of reported concussions rising, and additional precautions now being taken for an athlete's safety, more research is still needed with this particular population. Purpose: This study evaluated symptoms in Division I football players, as a baseline prior to a concussion event, using balance and an online computer test. Players, who were diagnosed with a concussion, were reevaluated. Methods: College football athletes (n = 87, 19.7 + 1.2 years, 184.2 + 2.5 cm, 100.7 + 7.6 kg), prior to the beginning of fall and spring football practice completed an initial baseline postural stability test and computerized concussion evaluation assessment. Players, who had a concussion (e.g., headache, dizziness, fatigue, confusion, and/or loss of consciousness) during practice or actual competition (n = 5, 19 + 0.6 years, 182.2 + 1.5 cm, 90.1 + 2.6 kg), completed 3 evaluations after injury, starting at 24 hours post-concussion for their balance assessment. When the player was considered asymptomatic, the test was repeated on the first and seventh day. They did retake the online concussion assessment. This study was only one segment of the overall evaluation provided to the decision makers (physicians, coaches, athletic trainers, and strength and conditioning coaches) in the concussed athlete's return-to-play decision. Results: The concussion group had a statistically significant (p = 0.032) change from their baseline balance score. This change remained significant until day 7 of post-testing. The concussion online assessment also was significant (p = 0.41) from their pre-test scores. The balance pre-test composite scores for all the players (n = 87) was 86.7 + 2.7 with their online assessment scores well within previously published acceptable norms. Conclusions: The balance and online concussion assessment tests, if available, should be considered as another assessment of concussed college-aged football players. This information may also provide additional scientific data to aid with the decision for the player to exercise, attend football practice and, possibly, return to play. Practical Application: Physicians, athletic trainers, football coaches, strength & conditioning coaches, exercise physiologists, and other involved professionals do need to continue to work together for the best care of an athlete. If SOT and online assessments are available, they should be used.

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22. Is There an Acute Loss of Shoulder Mobility Following Eccentric Resistance Training?

M. Kolber,1 G. Dudziek,1 L. Doherty,1 W. Hanney,2 C. Kuntz,1 B. Schoenfeld,3 P. Salamh,4 and S. Cheatham5

1Nova Southeastern University; 2University of Central FL; 3CUNY Lehman College, Department of Health Sciences; 4Southeastern Orthopedics Physical Therapy; and 5California State University Dominguez Hills

Purpose: Muscle performance exercise for the external rotators is often performed as part of shoulder rehabilitation and injury prevention programs. Evidence has highlighted the benefits of eccentric resistance training (EcRT) for the external rotators among individuals with shoulder disorders and those pursuing fitness endeavors. Although the benefits of EcRT are well-known, researchers have identified an acute loss of internal rotation (IR) mobility following high volume EcRT (9-sets of 25 repetitions) training. The importance of this finding resides in the association between IR mobility and shoulder disorders. Despite the aforementioned research, a paucity of evidence exists to determine the acute effect of EcRT on IR mobility when performed at a volume consistent with guidelines for rehabilitation and muscular fitness. The purpose of this study was to determine if an acute loss of shoulder IR mobility occurs following EcRT of the external rotator musculature. Methods: Twenty-five adults (mean age 24) without shoulder pathology were recruited. None of the participants routinely performed external rotator strengthening or shoulder stretching. The non-dominant arm was utilized to control for compulsory use of the dominant arm. Following consent, IR mobility (passive range of motion (PROM)) was measured with an Acumar digital inclinometer, using a previously validated technique with reported intraclass correlation coefficients (3,k) of ≥0.80. Following baseline measurements (PRE), side-lying shoulder external rotation (ER) was performed as a warm-up with a weighted dumbbell that allowed 20 isotonic repetitions without fatigue. Following the warm-up, 3-sets of eccentric-only ER repetitions were performed using a weighted dumbbell that allowed between 6-15 repetitions (based on ability) in accordance with previous research using EcRT. Participants were assisted as needed to ensure 6 minimum repetitions were performed. Initial IR PROM measurements were repeated immediately after (POST) the session and 24-hours later (P24) by the same investigator. Participants were advised to avoid shoulder stretching or strengthening for the 24-hour intersession period. Results: SPSS version 15.0 was used for analysis. A one-way repeated measures analysis of variance (ANOVA) with a Greenhouse-Geisser correction determined that IR PROM significantly changed (p < 0.001) between the time points of measurement. Post hoc pair-wise comparison tests using a Bonferroni correction revealed that the EcRT session elicited a significant loss of IR PROM (p < 0.001) from PRE to P24 (91 ± 14° (°) vs. 84 ± 12°, respectively). Significant differences were not present when comparing PRE and POST (p = 0.28). Conclusions: An acute loss of IR PROM was present following an EcRT session for the shoulder external rotators. These changes were evident 24-hours later and should only be generalized to the aforementioned dosing regimen. Practical Application: EcRT has gained attention in both fitness and rehabilitation professions based on favorable outcomes with regard to function and pain as well as fitness attributes. Results suggest that an EcRT session for the external rotators leads to an acute decrease in IR PROM, which subsequently has been associated with shoulder disorders. Implications for this finding resides in exercise prescription, as an acute loss of IR PROM would suggest that stretching after EcRT should be considered to mitigate a loss of IR mobility. Acknowledgments: The authors wish to thank the Department of Physical Therapy at Nova Southeastern University for providing the resources needed to conduct this study.

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23. The Prevalence of Hip and Pelvic Girdle Dysfunction in Collegiate Level Baseball Pitchers

K. Kumagai Shimamura, W. Chung, D. Farwell, D. Powers, J. Goetz, and K. Lindblom

Azusa Pacific University

Purpose: This a cross sectional study involving the assessment of pelvic girdle and hip function of all current baseball pitchers on the Azusa Pacific University and California State University San Bernardino rosters. Comparisons were made to cited norms of professional level baseball pitchers. Methods: Twenty-nine collegiate level baseball pitchers (age = 20.0 + 1.4 years, height = 80.7 + 34.5 cm; weight = 86.6 + 19.1 kg; body mass index = 25.7 + 2.7 kg) were recruited for this study. All subjects were assessed for hip flexion, internal rotation and external rotation range of motion (ROM), hip flexor length, Gluteus Maximus, Gluteus Medius and hip internal rotator (IR) and external rotator (ER) manual muscle test (MMT), Craig's’ test, femoral anterior glide with straight leg raise (SLR) test and hip motor control with prone active IR/ER test. Comparisons were made to cited norms of professional level baseball players. Statistical analysis included calculation of means and standard deviations, comparison of subject means with unpaired, 2-tailed t-test (p > 0.05). Results: Significant deficits exist in motor control of the both the dominant and non-dominant hips. Fifty two percent of the right handed and 50% of the left handed pitchers demonstrated poor motor control with an inability to stabilize the trunk and pelvis during active hip IR and ER. Thirty-four percent of the pitchers had a greater than 10° limitation in IR in sitting and 55% in prone compared to the norms. Fifty-six percent of the right-handed pitchers and 50% of the let handed pitchers demonstrated hip retroversion. There were no significant differences in the means of the collegiate players when compared to the norms of professional players as a group. Conclusions: Retroversion of the hip was present in 50% or more of the pitchers and may correlate with the decrease in internal rotation ROM. Motor control deficits were present in 50% or more of the pitchers even though isolated strength deficits were not detected at a significant level. Practical Application: Limitations in motor control of the hip can alter normal biomechanics of the pitching cycle resulting in abnormal stresses placed on the surrounding body regions. Retroversion and the correlated limited hip IR may lead to mechanical impingement of the hip and early degenerative changes. Additionally assessing muscle strength and mobility in isolation can be misleading and may not be enough to ensure optimal performance during a baseball pitch. Motor control of the trunk, pelvic girdle and hip must be assessed as a functional unit to determine if optimal power transmission occurs though the hip and trunk. These findings suggest that collegiate level baseball players as a whole match the norms of professional level baseball pitchers. However, assessment of the hip for retroversion and motor control are critical components, which are often overlooked.

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24. Influence of Aging on Rapid Velocity Characteristics and Relationships With Peak Torque of the Leg Extensors

B. Thompson,1 E. Conchola,2 M. Stock,1 and T. Palmer2

1Texas Tech University; and 2Oklahoma State University

Previous studies have reported age-related declines in muscular strength, power, and rate of force development characteristics. However, we are aware of no studies that have examined the effects of aging on the rate of velocity development (RVD), which may also be an important contributor to the loss of function observed in older adults. Purpose: To investigate the age-related differences in rapid velocity characteristics between young and old men and the relationships of these characteristics with peak torque (PT) of the leg extensor muscles. Methods: Twenty-three young (mean ± SD: age = 25.1 ± 3.0 years; height = 178.8 ± 7.7 cm; mass = 88.1 ± 21.5 kg) and 21 old (age = 72.0 ± 4.4 years; height = 177.6 ± 6.4 cm; mass 85.4 ± 11.3 kg) men volunteered for this investigation. Participants were familiarized on the testing procedures during the first laboratory visit. Within 48–72 hours following familiarization, participants performed 2-3 maximal voluntary contractions (MVCs) on an isokinetic dynamometer at velocities of 240°·s−1 and maximum unloaded velocity (Vmax). One minute of rest was provided between all MVCs, and during each MVC participants were instructed to push “as hard and fast as possible.” Torque signals were gravity corrected for the weight of the limb and peak torque (PT, Nm·kg−1) was determined from the highest 25 ms epoch of the torque-time curve at the 240°·s−1 velocity. RVD (°[BULLET OPERATOR]s−2) was calculated as the linear slope of the velocity-time curve from the onset of velocity to the point where the velocity reached 2°·s−1 below the peak velocity (i.e., 238°·s−1 for the velocity of 240°·s−1). Vmax was the maximal velocity attained during the highest unloaded MVC. Independent t-tests were used for group comparisons and Pearson product-moment correlation coefficients (r) were used to evaluate the relationships among PT and rapid velocity variables. Results: The young men exhibited greater PT, RVD, and Vmax compared to the old men (p < 0.01, Figure 1). The Pearson correlations revealed that PT was correlated to RVD (r = 0.81; p < 0.01) and Vmax (r = 0.78; p < 0.01). Conclusions: The present findings showed markedly reduced RVD (37.3%) capacities in old men which were similar in magnitude to reductions in isokinetic PT (38.1%). In addition, peak velocity (Vmax) capacities declined a significant 10.1% across the lifespan. The rapid velocity characteristics were correlated to PT, showing that PT was able to explain 66 and 61% of the variance in RVD and Vmax, respectively. Practical Application: The ability of older adults to attain rapid velocities of the lower limb may be diminished. In addition to declines in torque- or strength-related capacities, velocity impairments may also contribute to age-related declines in performance and functional abilities. Professionals may consider implementing both strength and velocity assessments and training components into programs aimed at improving the physical function of the elderly.

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25. Tracking the Rates for Injuries and Correlations for Days Missed of Training for the Texas A&M Corps of Cadets

G. Darling,1 J. Carter,2 K. Brooks,3 L. Greenwood,2 and M. Greenwood2

1TAMU; 2Texas A&M University; and 3Texas A&M University–Corpus Christi

Texas A&M University has one of the largest and most distinguished Reserved Officer's Training Corps (ROTC) programs in the nation. Currently the Texas A&M Corps of Cadets has over 2,000 members. Life for the cadet is very demanding, requiring supplementary college courses in addition to their normal course work, intense physical training (PT), and mandatory social events. Research has shown that a major predictor for future injuries in the military is prior injuries. Purpose: The purpose of this study was to determine the common causes and correlations for injuries and injury rates in the Texas A&M Corps of Cadets. Methods: This study occurred over the Fall 2013 semester. During the semester, the research team monitored the injury rates for first Brigade, one of the brigades in the Corps of Cadets that consisted of 192 cadets (167 males, 25 females), 39 seniors, 43 juniors, 51 sophomores, and 59 freshmen. During the fall semester, when a cadet could not participate fully in PT with their unit, they would report to the Leadership Learning Center (LLC). While at the LLC, the cadets would fill out an injury questionnaire designed by the research team. The cadet would fill out the entire questionnaire on the first visit except for 2 questions (How many training sessions did you miss? and How many days were you injured?). After fully returning to PT, the cadets would return to the LLC and complete the last 2 questions. Results: Significant correlations were found between Core Fitness Test Scores (CFTS) and age (p < 0.01, r = 0.434), and years in corps (p < 0.01, r = 0.634). Regarding injuries, significant correlations were observed between CFTS and shoulder, knee, and ankle joint injuries (p < 0.01), as well as a correlation between incidence of ligament injury, heat injury, other illness, muscle injuries in the abdominal, lower back, and hamstring regions, with days missed, sessions missed, and CFTS (p < 0.01). A significant correlation (p < 0.01) between injury and age, gender, and years in corps was also present. Conclusions: Injuries were more associated with the female gender, the freshmen cadets, and those of lower fitness levels for joint, ligament, muscular, and heat injuries, as well as more frequent illnesses. Practical Application: Preventing injuries from occurring in the first place is of the utmost concern for the ROTC cadet. Prior injuries are a predictor of future injuries in the military. It appears that the most frequently injured, as well as those missing the most days of training due to injuries and illnesses in the Texas A&M Corps of Cadets, are the less fit, the freshmen cadets, and the female cadets. This is of critical importance because when military personnel are injured, it negatively affects military readiness, as well as the daily college lives of the cadets. Acknowledgments: The research team would like to acknowledge the Texas A&M Corps of Cadets.

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26. Shoulder Strength, Flexibility, and Postural Characteristics Among Naval Special Warfare Students With and Without History of Shoulder Injury

T. Nagai, T. Sell, J. Abt, M. Varnell, S. Eagle, and S. Lephart

University of Pittsburgh

Naval Special Warfare Sea, Air and Land Qualification Training (SQT) students are required to complete physically and mentally vigorous tactical training courses to become an Operator. Due to years of physical and tactical training working up to and during SQT, it is common to see SQT students with a prior history of musculoskeletal injuries. Specifically for those with a history of shoulder injury, it is of interest to see if they exhibit alterations in shoulder strength, flexibility, and posture. Purpose: To evaluate differences in musculoskeletal characteristics of the shoulder between those with and without a history of shoulder musculoskeletal injuries. Methods: One hundred seventy-five SQT students volunteered to participate in comprehensive laboratory testing. Based on self-reported history of shoulder injuries, subjects were assigned to one of 2 groups: no injury group (NoInj) or an injury history group (InjHist). 162 SQT students had no history of shoulder injury (mean ± SD; age = 24.1 ± 2.7 years; height = 179.0 ± 5.8 cm; mass = 84.4 ± 7.9 kg) and 13 students had a history of shoulder injury (age = 23.9 ± 1.8 years; height = 181.5 ± 7.1 cm; mass = 84.7 ± 9.1 kg; time from injuries = 363 ± 165 days). For those students who had a history, shoulder injuries were on their right (n = 5), left (n = 7), or both shoulders (n = 1) and occurred during physical training (n = 5), weight training (n = 4), or Basic Underwater Demolition/SEAL training (n = 4). Shoulder internal/external rotation (IR/ER), elevation (ELE), and protraction/retraction (PRO/RET) strength was measured using an isokinetic dynamometer. Strength values were normalized to body weight (%BW). Passive shoulder IR/ER, flexion (FLE), and extension (EXT) range-of-motion (ROM) and posterior scapular tightness (PST) were measured using a digital inclinometer. Forward shoulder posture (FSP) and pectoralis minor length (PML) were measured using a double-square device. All assessments were completed bilaterally, and side-to-side differences were calculated as a ratio of right over left side. Each variable was screened for normality using Shapiro–Wilk test. Based on the normality, either independent t-tests or Mann–Whitney U tests were used to compare between the groups. Statistical significance was set at p ≤ 0.05 a priori. Results: There were no significant differences for any strength variables. The InjHist group had significantly less left shoulder ER ROM (NoInj: 111.1° ± 9.2°, InjHist: 106.3° ± 4.4°, p = 0.004) and increased right FSP (NoInj: 15.7 cm ± 2.0 cm, InjHist: 17.0 cm ± 2.2 cm, p = 0.031). The side-to-side difference on shoulder FLE ROM differed significantly between the groups (NoInj: 1.00 ± 0.03, InjHist: 1.04 ± 0.05, p = 0.016). Conclusions: Given the decreased ROM, increased forward posture, and greater side-to-side difference that appear to be associated with injury, it is important to assess flexibility, posture, and side-to-side differences as a part of routine physical fitness evaluation. Addressing specific suboptimal characteristics is an important step to keep Operators injury-free and extend their career. Practical Application: Although all students in InjHist were cleared for physical and tactical training, subtle alterations in ROM, posture, and side-to-side differences still exist. Periodical laboratory testing plays a critical role as a means to objectively monitor and track Operators' musculoskeletal needs over their career. Acknowledgments: ONR#N00012-11-1-0929.

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27. Relationship Between Anthropometric Measures and Upper-Body Muscular Endurance of Part-Time Special Weapons and Tactics Team Officers

E. Ostermann, J. Dawes, C. Elder, and S. Woodworth

University of Colorado–Colorado Springs

Muscular endurance is considered important to successfully perform many essential job-related tasks related to the Special Weapons and Tactics Team (SWAT), such as during use of force situations, maintaining tactical positions for extended time periods while wearing protective gear and carrying specialized equipment. Thus, low levels of upper-body muscular endurance may lead to an increased risk of injury, especially in the low back, and reduced occupational performance among SWAT officers. Purpose: The purpose of this study was to investigate the relationship between anthropometric measures and muscular endurance performance among Tactical Officers. Methods: Data for 37 male tactical officers (N = 37, age 36.72 ± 4.20 years) was provided to the primary investigator via team commanders for statistical review. This data related to 2 measures of upper-body muscular endurance; a 2-minute push-up test (PU) (74.73 ± 16.84), and 2-minute sit-up test (SU) (67.43 ± 16.76). In addition, anthropometric information of height (HT), weight (WT) and percentage of body fat (BF%) and Body Mass Index (BMI) (mean ± SD.; HT. 177.01 ± 6.2 cm; WT 89.45 ± 10.56 kg; BF% 15.53 ± 5.88; BMI 28.4 ± 3.5) were also provided. Collected data was statistical analyzed using the SPSS 21.0 statistical software package. Results: Pearson's correlations identified significant strong negative correlations between PU and BF% (r = −0.699, p < 0.01), and PU and fat mass (FM) (r = −0.717, p < 0.01) and significant low negative relationships between BMI and PU (r = −0.3.64, p < 0.01). Strong negative correlations were also discovered between SU and BF% (r = −0.759, p ≤ 0.05), SU and FM (r = −0.750, p < 0.01), as well as a moderate negative relationship between SU and BMI (r = −0.603, p < 0.01). Conclusions: The results of this study suggest that increased body fatness among tactical officers may have a negative impact on certain measures of upper-body muscular endurance performance. Practical Application: Many tactical officers are required to perform these fitness tests as part of their special team's assessment and selection criteria. Increased adiposity may be one factor that could hinder performance when performing these tests as a greater fat mass increases physiological burden.

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28. Comparison of Combined Laboratory and Field-Based Tests to Standardized Testing of Physical Fitness in Police Academy Cadets

R. Sherman, A. Crawley, and W. Crawley

Grand Valley State University

Physical fitness is a vital component of assessing readiness to work, especially in tactical athletes. However, it has been assessed using any number of different tests, and in either a controlled laboratory or ecologically valid field environment. Purpose: The purpose of the study was to compare the ranking of physical fitness determined from lab and field based tests with state standardized tests in police academy cadets. Methods: Fifty-two police academy cadets (46 males and 6 females; age 23 ± 3 years; height 178 ± 8 cm; body mass 83.4 ± 13.0 kg) volunteered to undergo a battery of combined laboratory and field-based fitness tests (L&F) and police academy standardized fitness tests (PA) at weeks 1, 8, and 16. The lab-based tests were maximal grip strength, 20 seconds maximal arm crank, and sum of 7-site skinfolds. The field-based tests were a 40-yard sprint, 1-RM bench press, T-test, vertical jump, and sit-and-reach flexibility. Cadets also completed the PA testing, which was number of push-ups and sit-ups completed in 60 seconds, and a half-mile shuttle run. Cadets participated in a physical training program for 1 hour, 3 days a week, for 16 weeks, with targeted components of cardiovascular endurance, absolute and dynamic strength, and flexibility. At each time point (Week 1, 8, and 16) Spearman correlations (ρ) were used to assess the relationship of ranked: (a) “overall” physical fitness; and (b) 1-RM bench press and number of push-ups between L&F and PA testing. Results: A combined L&F physical fitness ranking was significantly (p < 0.01) related to PA physical fitness ranking at all 3 time points. Week 16 exhibited the strongest relationship (ρ = 0.673), however both Week 1 (ρ = 0.650) and Week 8 (ρ = 0.639) had a similar magnitude of relationship. Also, significant (p < 0.01) relationships were found at all 3 time points between ranked performances in the 1-RM bench press and the PA push-up test. The strongest relationship was found at Week 1 (ρ = 0.653) although both Week 8 (ρ = 0.523) and Week 16 (ρ = 0.500) also had positive relationships. Conclusions: The relative stability in the relationship of ‘overall’ physical fitness determined from combined lab and field-based testing and police academy standardized testing indicates that changes in physical fitness during the 16-week academy were generally reflected in both testing ‘conditions’. The weakening relationship, across the 16-weeks of the academy, between performance of a 1-RM bench press and number of push-ups completed may be a result of the changes in and differences when assessing upper body strength and endurance. Practical Application: These findings suggested that the use of combined lab and field-based tests or alternatively, standardized testing, should enable a professional or organization to adequately assess overall physical fitness. However, care must be taken when assessing test results to ensure appropriate and valid interpretation of physical fitness. Moreover, ecologically valid or functional physical fitness tests could improve the usefulness of standardized testing as a determinate of readiness to work.

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29. Relationship Between Body Composition and Sustained Anaerobic Power Among Special Weapons and Tactics Team Officers

S. Woodworth, J. Dawes, C. Elder, and E. Ostermann

University of Colorado–Colorado Springs

Sustained anaerobic power is a physiological attribute that is essential in tactical situations that requires force to be expressed rapidly, such as when sprinting and dodging; stair climbing and during sustained pursuits. Purpose: The aim of this investigation was to examine the relationship between estimated body fat percentage (BF%), fat mass (FM) and 300 meter run scores among Special Weapons and Tactics (SWAT) team members. Methods: Archival data for 40 (n = 40, age 37.63 + 5.2 years) male tactical officers belonging to a part and full-time SWAT team were provided to the primary investigator, via team commanders, for statistical review. Data related to 300 meter run times (300-m), height (HT), weight (WT), percentage of body fat (BF %) and Body mass index (BMI) (mean + SD.; HT. 177.01 + 6.2 cm; WT 89.45 + 10.56 kg; BF% 15.53 + 5.88; BMI 28.4 + 3.5) was recorded. BMI was calculated using the Quetlet Index. Collected data was statistical analyzed using the SPSS 21.0 statistical software package. Results: Pearson Correlation indicated a strong positive correlations between BF% and 300-m (r = 0.827, p < 0.01), strong positive correlations between FM and 300-m (r = 0.773, p < 0.01), and a moderate positive correlation between BMI and 300-m (r = 0.528, p < 0.01). Conclusions: The results of this study suggest that increased body fatness amongst SWAT officers may have negative effects on measurements of sustained anaerobic power. Practical Application: Increased body fatness may limit the capacity for SWAT team members to adequately sustain powerful movements, and therefore limit their effectiveness. Additionally increased physiological burden of protective gear and equipment may further hinder performance. Thus, improving body composition may help improve occupational performance, and reduce risk of injury, when sustained anaerobic power is required.

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30. Acute Arginine Supplementation Does NOT Augment Muscular Strength in Southeastern Conference D1 Female Athletes

E. Hall,1 B. Wax,1 and A. Kavazis2

1Mississippi State University; and 2Auburn University

Purpose: Nitric-oxide stimulators (NOS) are being marketed as being able to increase muscular performance; however, a paucity of research exist regarding these claims on female athletes. Therefore, the purpose of this study was to investigate the impact of supplemental arginine ingestion on muscular strength output in Southeastern Conference D1 female athletes. Methods: Seven athletic females (age = 21.28 ± 0.92 years; mass = 76.1 ± 2.6 kg, bodyfat % = 22.02 ± 1.57; height = 167.6 ± 1.19 cm) ingested L-arginine (3 g) or a placebo (PL) 45 minutes prior to exercise in a randomized, double-blind crossover design. Participants were free of any medical condition and refrained from any demanding upper body activity 72 hours prior to testing and any lower body activity 24 hours prior to the testing sessions, respectively. Upon reporting to the lab, participants sat quietly for 5 minutes. Next, subjects ingested arginine (3 g) or a placebo (PL) and rested for 45 minutes. Next, resting blood pressure and heart rate were obtained. After a warm-up, participants performed one-repetition maximum (1-RM) testing on the bench press followed by a 10-minute recovery period. Next, participants rode a stationary cycle for 5 minutes, followed by a 3 warm up bouts on the leg press, and then performed 1-RM testing for the lower body. Results: Analysis revealed no significant differences for measures of 1-RM strength on either the bench press (p > 0.05) or leg press (p > 0.05) between the treatments. Additionally, blood pressure and heart rate were similar at rest and immediately following 1-RM in both the arginine and PL groups. Conclusions: Arginine may not provide any ergogenic benefits in females for measures of muscular strength in either the upper- or lower-body for female athletes. Practical Applications: Oral ingestion of arginine does not enhance muscular strength in female athletes, and may be limited in its effectiveness by hepatic and intestinal metabolism.

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31. Effects of Dietary Change on Blood Markers During Five Days of Overreaching in Active Females

S. Hayward,1 S. Urbina,2 J. Outlaw,1 J. Holt,3 B. Burks,3 E. Faillace,1 M. Stone,3 A. Regelski,1 M. Sauer,4 K. Villa,1 J. Mullins,1 C. Foster,4 L. Taylor,4 A. Smith-Ryan,5 and C. Wilborn4

1Human Performance Lab at University of Mary Hardin-Baylor; 2Human Performance Lab at University of Mary Hardin Baylor; 3Human Performance Lab; 4University of Mary Hardin-Baylor; and 5The University of North Carolina at Chapel Hill

Purpose: The purpose of this study was to determine what effects a balanced diet can have on specific blood variables during 5 days of overreaching workouts. Methods: Twenty-three recreationally active females (mean ± SD; 20.52 ± 2.04 years; %body fat: 28.27 ± 6.15) participated in the 9-week study, completing 3 resistance training workouts per week for weeks 1–3 and 4 workouts per week for weeks 4–8. Week 9 consisted of 5 consecutive days of overreaching (8 sets of 10 repetitions at 70% of one-rep maximum on bench press, deadlift, squat, and thruster). A 7-day diet log was kept during week 1 to determine baseline nutritional intake. Participants were matched according to Healthy Eating Index (HEI) dietary analysis score and randomly assigned to 1 of 3 groups: no diet change (CTR), diet change (DC), or diet change plus creatine (DCC; 5 g/d). The CTR group was instructed to eat the same foods as reported on the initial 7-day diet log. DC and DCC were given specific guidelines on the number of servings of fruit, vegetables, whole grains, protein, and dairy to eat each day as well as how much water to drink. Daily food logs were recorded using the MyFitnessPal app. Participants completed strength and body composition testing at the end of weeks 4 and 8. Blood was drawn during week 4 and before the first overreaching workout for baseline measurement (T2 & T4) before each overreaching workout, 24 hours after the previous overreaching workout (T4-T9) during week 8. Blood was analyzed for Interleukin-6 (IL-6), Cortisol (COR), Testosterone (TST), and C-Reactive Protein (CRP) using one-way ANOVAs, repeated measures, and change scores. Results: IL-6 analysis revealed no significant differences between groups at any time point. Change score analysis revealed a significant decrease in COR from T8 to T9 (p = 0.019) for DC compared to the increase seen in CTR (p = 0.006) and DC compared to the lesser decrease in DCC (p = 0.040). No differences were seen for TST or CRP. HEI significantly increased (p = 0.000) from baseline to week 8 for DC (+313%) and DCC (+297%) with no significant change for CTR. Significant improvements were seen for both intervention groups for protein (p = 0.025), water (p = 0.018), and Ω3 (p = 0.000) intake compared to the control. Conclusions: While nutrition status improved over the course of the dietary intervention, no benefits were seen in regards to anabolic and stress hormone levels. Significant improvements in the circulating level of COR from 24 hours after workout 4–24 hours after workout 5. Practical Application: Results suggest that a 4 week dietary intervention, although capable of increasing overall nutrition, was ineffective in creating an anabolic environment (seen by an increase in TST). Also, increasing nutrition did not produce a decreased CRP, COR, or IL-6 response, when compared to the control group. Future studies should investigate the length of dietary intervention. While analyzing, hormone levels within 1 hour of the overreaching workout to determine if an elevated response was see in the CTR group compared to the DC or DCC groups.

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32. Hormonal Responses to Consecutive Carbohydrate Supplementation During Heavy-Resistance Exercise

K. Kim,1 H. Jung,1 P. Kim,2 J. Ryu,1 and H. Kang1

1Kyungpook National University; and 2Youngin University

This study investigates the hormonal response to consecutive carbohydrate supplementation during heavy-resistance exercise. Ten male students (age: 23.2 ± 0.4 years; height: 174.1 ± 2.0 cm; body weight: 68.4 ± 1.7 kg) randomly received either exercise treatment (8 RM) or exercise/carbohydrate (8 RM/CHO). The 8 RM/CHO group ingested carbohydrate (1.2 g/kg) between resistance exercise sessions. Each session consisted of 5 sets of leg press exercise with a maximum of 8 repetitions (8 RM), and there were 4 sessions during the 2-hour experimental period. Blood samples were drawn immediately before exercise (0) and in 15-minute intervals during the 2-hour period. Plasma human growth hormone (hGH), total testosterone, cortisol, insulin, and glucose concentrations were determined. The plasma glucose level was significantly higher in 8 RM/CHO at 15, 30, 45, 60, and 90 minutes than 8 RM (p ≤ 0.05). the plasma insulin level was significantly elevated in 8 RM/CHO (p ≤ 0.05) until the end of the experimental period, but there was no change in 8 RM. The plasma hGH level in 8 RM was significantly elevated between 30 and 90 minutes (p ≤ 0.05), but this elevation was completely blocked in 8 RM/CHO. There was no significant difference in the cortisol level between the 2 treatment methods. The testosterone level decreased significantly in 8RM/CHO (p ≤ 0.05) through the end of the experimental period, but there was no change in 8 RM. These results suggest that the consecutive ingestion of carbohydrate during resistance exercise reduced the level of total testosterone, blocked the elevation of hGH, and increased the insulin level.

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33. Antioxidant Preconditioning Strengthens the Skeletal Muscle Function During Hypoxia

M. Koozehchian,1 R. Kreider,1 W. Roberts,2 and L. Zuo3

1Texas A&M University; 2Ohio State University; and 3School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine

Exposure to hypoxia may cause severe muscle damage. Antioxidant preconditioning (AP), which employs a few cycles of antioxidant treatments prior hypoxia, may attenuate hypoxic injuries. Purpose: We hypothesized that AP treatment can improve skeletal muscle function during hypoxia. Methods: In our current study, Tiron, a powerful antioxidant, was injected (1 g/kg; IP) into the mice once per day, 5 days per week. Following antioxidant treatment, diaphragm muscle was isolated from the sacrificed mice. The muscles were loaded into the contraction chamber containing Ringer's solution and a function assay was performed under a simulated hypoxic condition. Results: Tiron treated mice showed ∼ twofold increase in % of maximal force compared to control during hypoxia, showing an enhanced function by Tiron treatment (p ≤ 0.05). Data were analyzed using a 2-way ANOVA, and presented as means ± SE. The differences between the various factors were determined by post-ANOVA contrast analysis using SAS-JMP software. p ≤ 0.05 was regarded to be significant. Conclusion and Practical Application: Our data suggest that AP effectively boosts the diaphragm muscle function and force development during hypoxia. Thus, we infer that AP is an effective treatment to reduce hypoxic damage, which may potentially help strengthen the skeletal muscle in athletes to prevent cellular damage in response to free radicals.

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34. The Safety of Chronic Creatine Nitrate Supplementation: A 28 Day Evaluation

M. Mosman

MusclePharm

The ergogenic effects of creatine monohydrate (CM) has made it one of the most widely used supplements in various populations. It is estimated that 28–41% of NCAA athletes are using CM in 17 different sports while 29–57% (military vs. civilian) of health club members use CM. The safety of CM on blood chemistry and hematology values has been well established. However, little is known about the impact of various other forms of creatine on safety parameters, specifically creatine nitrate (CN). Purpose: To determine the safety of ingesting a CN supplement for 28 days. Methods: Twenty men between the ages of 18 and 31 participated in the study. Subjects were instructed to report to the blood testing facility in an 8 hours fasted, euhydrated state and not to exercise the morning of testing. Subjects then provided a baseline blood and urine sample for full safety panels (for a full list of variables, see table 1), height, weight, blood pressure, and heart rate. Subjects were divided into 2 groups: group 1 (n = 10) was instructed to consume 1 g daily of CN, while group 2 (n = 10) was instructed to consume 2 g daily for 28 days. After baseline measurements were completed subjects were provided with the CN supplement and instructed to record a supplementation and adverse events log for 28 days. They were also instructed to maintain their current diet and exercise routine as it had been for at least 2 months prior to the start of the study. At the conclusion of the 28 days supplementation period, subjects were instructed to return to the blood testing facility in an identical state to baseline testing to provide a blood and urine sample, height, weight, blood pressure, and heart rate. Results: Over the 28 days CN supplementation period no statistically or clinically significant changes in blood chemistry or hematology were observed. No adverse events were reported in this study. Conclusions: Chronic CN supplementation appears to be safe in male populations when taken within recommended usage guidelines. Practical Application: CN supplementation appears to be a safe alternative to CM in male populations. As an ergogenic aid CN may be as effective as CM in producing greater strength and fat-free mass development; however more studies comparing CN to CM are needed to confirm this theory. Acknowledgments: This investigation was supported by a grant from MusclePharm, Corp.

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35. Effects of Dietary Intervention on Performance During Five Days of Overreaching in Active Females

J. Outlaw,1 S. Urbina,2 S. Hayward,1 J. Holt,3 B. Burks,3 E. Faillace,1 M. Stone,3 A. Regelski,1 M. Sauer,4 K. Villa,1 J. Mullins,1 C. Foster,4 L. Taylor,4 A. Smith-Ryan,5 and C. Wilborn4

1Human Performance Lab at University of Mary Hardin-Baylor; 2Human Performance Lab at University of Mary Hardin Baylor; 3Human Performance Lab; 4University of Mary Hardin-Baylor; and 5The University of North Carolina at Chapel Hill

Purpose: The purpose of this study was to determine what effects a dietary intervention with a balanced diet high in antioxidants may have on performance during 5 days of intense overreaching training. Methods: Twenty-three recreationally active females (mean ± SD; 20.52 ± 2.04 years; %body fat: 28.27 ± 6.15) finished the 9-week study, completing 3 resistance training workouts per week for weeks 1–4 and 4 workouts per week for weeks 5–8. Week 9 consisted of 5 consecutive days of overreaching [D1-D5; 8 sets of 10 reps at 70% of 1-rep max (1RM) on bench press (BP), deadlift (DL), squat (SQ), and thruster (TH)]. The participants were matched according to baseline Healthy Eating Index score (HEI) and randomly assigned to one of 3 groups: no diet change (CTR), diet change (DC), or diet change plus creatine (DCC). CTR was instructed to eat the same foods as reported via a 7-day diet log during week one (analyzed with ESHA Food Processor software). DC and DCC were required to eat a specific number of servings of fruit, vegetables, dairy, grains, and protein according to caloric needs. Daily food intake was monitored with MyFitnessPal. Participants completed 1RM and body composition testing (dual-energy x-ray absorptiometry) at the end of weeks 4 and 8. The number of completed reps for each set and exercise was recorded during each workout on D1-5. Total training volume for each lift, day, and week was calculated. Performance data was analyzed using one-way ANOVAs, repeated measures, and change scores. Post hoc analysis was used to determine where significance lay. Significance was set at p = 0.05. Results: There were significant time effects for lean mass, %body fat, and BP, DL, SQ, and TH 1RM. BP reps for D1 approached significance (p = 0.057) with a significant difference between CTR and DC (p = 0.018). BP reps for D3 and D5 was significant with differences between CTR and DC (p = 0.009) and CTR and DCC (p = 0.022). There were no significant changes for DL, SQ, or TH total reps. BP training volume was significantly different among groups (p = 0.014) with post hoc revealing the difference to be between CTR and DCC (p = 0.004). There was a trend for significance for total weekly volume for BP (p = 0.06) and TH (p = 0.097) with significant differences between CTR and DCC for both variables. Change scores for SQ volume was significantly changed (p = 0.042) from D1 to D4 between CTR and DC. DC and DCC both had significantly (p = 0.000) improved HEI scores (+313% and +297%, respectively) in addition to significant increases in protein (p = 0.025), water (p = 0.018), and Ω3 (p = 0.000) intake over CTL. Conclusions: HEI improvements occurred via an increase in the number of servings of fruits, vegetables, protein, whole grains, and Omega-3 for 4 weeks. This intervention resulted in no changes in performance or differences in total volume of work during the 5 day overreaching protocol except for BP on D3. Body composition changes indicate that the training regimen was successful and on D3 of overreaching, significant differences in total volume between CTR and DCC did occur. In conclusion, 4 weeks of dietary intervention does not improve performance during intense training. Practical Application: Results suggest that dietary intervention lasting 4 weeks has little to no beneficial effects on performance during an overreaching protocol. Future research should focus on length of intervention to determine effectiveness of diet change.

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36. A Comparison of Electrolyte-Carbohydrate, Electrolyte-Amino Acid, and Water Beverages on Rehydration in Healthy Men and Women

C. Tai

MusclePharm Sports Science Institute

In cases of dehydration exceeding a 2% loss of body weight, athletic performance can be significantly compromised. Carbohydrate and/or electrolyte containing beverages have demonstrated efficacy for rehydration and recovery of performance, yet surprisingly, there is insufficient research on amino acid containing beverages in combination with electrolytes. Purpose: The purpose of this study is to compare the rehydration capabilities of electrolyte-carbohydrate (EC), electrolyte-amino acid (EA), and water (W) beverages. Methods: Ten males (26.7 ± 4.58 years; 174.3 ± 6.36 cm; 74.2 ± 10.9 kg) and 10 females (27.1 ± 4.72 years; 175.3 ± 7.87 cm; 71.0 ± 6.54 kg) participated in this double-blind, crossover study. Each participant visited the laboratory a total of 4 times. During the first visit, participants were familiarized with testing protocols. Visits 2–4 consisted of the following series of protocols with 3 different beverages consumed during the rehydration period: baseline measurements, dehydration, measurements, rehydration, followed by 4 more measurements immediately following rehydration and at 1, 2, and 3 hours post rehydration. Each visit was separated by a 7 days washout period. Each measurement session consisted of urine volume, urine specific gravity, drink volume, and water retention. The dehydration protocol consisted of 30 minutes of running at 80% maximum heart rate coupled with 15 minutes sauna intervals until approximately 2% of body weight was lost. Rehydration beverages were administered in a randomized order and consisted of an EA beverage (Amino 1, MusclePharm), an EC beverage (Gatorade), and a W beverage (Crystal Light). Results: No significant differences (p > 0.05) existed between beverages for urine volume, drink volume, or water retention for any time point. Condition x time interactions existed for urine specific gravity (USG) (p ≤ 0.05). Post hoc analysis revealed differences occurred between the W and EA beverages (p = 0.003) and between the EC and EA beverages (p = 0.007) at 4 hours after rehydration. Conclusions: Because there were no differences in urine volume, drink volume, or water retention, yet USG decreased, the EA supplement would appear to increase cellular rehydration. Practical Application: Athletes at risk for dehydration can adequately rehydrate using an EA beverage with possible benefits over an EC or W beverage. Acknowledgments: This investigation was supported by a grant from MusclePharm, Corp.

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37. Acute Effects of an Arginine-Based Supplement on Metabolic, Ventilatory, and Neuromuscular Fatigue Thresholds

R. Zak, E. Hill, M. Monaghan, A. Kovacs, G. Wright, and C. Camic

University of Wisconsin–La Crosse

Purpose: To examine the acute effects of an arginine-based supplement on the lactate threshold (LT), ventilatory threshold (VT), respiratory compensation point (RCP), peak oxygen consumption rate (

), and physical working capacity at the fatigue threshold (PWCFT). Methods: This study used a double-blinded, placebo-controlled, crossover design. Nineteen untrained men (mean age ± SD = 22.0 ± 1.7 years; body mass = 79.4 ± 9.0 kg; height = 177.0 ± 5.3 cm) volunteered to visit the laboratory on 3 occasions. During the first visit, subjects performed an incremental test to exhaustion on an electronically-braked cycle ergometer to familiarize the subjects with the testing procedures. Following a 1-week rest period, subjects came in for a second visit and were randomly assigned to ingest either the supplement or placebo. The supplement contained 3 g of arginine, 300 mg of grape seed extract, and 300 mg of polyethylene glycol (PEG). The placebo was microcrystalline cellulose. After randomization, the subjects ingested one dose of either the supplement or placebo and sat quietly in the laboratory for 60 minutes. Following the 60-minute period, the subjects performed an incremental test to exhaustion on an electronically-braked cycle ergometer for determination of LT, VT, RCP,

, and PWCFT. The incremental test began at 50 W and increased 30 W every 2 minutes until voluntary exhaustion or the subject could not maintain a pedal cadence of 70 rev·min−1. The VT and RCP were determined by noninvasive gas exchange measurements using the V-slope method. Surface electromyographic (EMG) signals were recorded from the vastus lateralis using a bipolar electrode arrangement for determination of the PWCFT. Following another 1-week rest period, the subjects returned to the laboratory for the third visit that involved ingestion of the opposite substance (supplement or placebo) and were retested utilizing the same procedures as the second visit. Results: The results of the paired-samples t-test indicated there were significant (p ≤ 0.05) mean differences between the arginine and placebo conditions for the VT (2512 ± 306 vs. 2407 ± 312 ml/min) and PWCFT (196.1 ± 45.0 vs. 166.1 ± 52.2 W), but not the LT (138.4 ± 29.1 vs. 136.8 ± 22.1 W), RCP (2866 ± 362 vs. 2923 ± 395 ml/min), absolute

(3661 ± 432 vs. 3684 ± 458 ml/min), or relative

(46.5 ± 5.8 vs. 46.7 ± 5.3 ml/kg/min). Conclusions: The present findings indicated that a single dose of the arginine-based supplement increased the VT (4.4%) and PWCFT (18.1%), but not the LT, RCP, or

. It is possible that these results were attributed to the enhanced blood flow through increased nitric oxide production and decreased endothelin production that is associated with arginine and grape seed extract supplementation. Practical Application: These findings support the use of the arginine-based supplement, at the dosage examined in the present investigation, as an ergogenic aid for improving the VT and delaying the onset of neuromuscular fatigue (i.e., PWCFT) in untrained individuals. Acknowledgments: This study was supported by NSCA/GNC Nutritional Research Grant.

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38. An Evaluation of the Heart Rate Response to a Thirty Minute WII Sports Resort Canoeing Exergaming Session

A. Bosak,1 M. Nelson,2 J. Carter,1 and K. Huet1

1Armstrong Atlantic State University; and 2Exodus Chiropractic

Leading a very busy lifestyle often makes it hard to complete daily physical activity. Thus, finding alternative exercise methods that can assist individuals with “sneaking physical activity” into their daily life is paramount. Furthermore, compliance rates for participation in physical activity increase when the activity is considered fun to do. Coincidently, playing video games is often considered a fun activity and rather recently, the use of interactive video games, as a potential mode of exercise, has been assessed utilizing a variety of “exergames.” However, despite how fun playing Nintendo Wii Sports Resort Canoeing (WSRC) can be, this particular exergame has not been evaluated to confirm if it could serve as a form of cardiovascular exercise. Purpose: To determine if playing 30 minutes of WSRC yields a Heart Rate Response (HRR) that meets the American College of Sports Medicine (ACSM) guidelines for moderate physical activity intensity as indicated by a HRR intensity of 64–76.9 percent of a subject's maximum heart rate (HRmax). Methods: Twenty-seven above averagely fit collegiate males participated in a maximal treadmill graded exercise test (GXT) to measure HRmax and maximal oxygen consumption (

) and then, 3–7 days later, completed a 30 minutes WSRC exergaming session. The mean HRR of the 30 minutes WSRC session was recorded for each individual and reported as a percentage of their HRmax. Starting and ending Heart Rate (HR) and Rating of Perceived Exertion (RPE) values were assessed using ANOVA statistical methods with significant differences considered at p ≤ 0.05. Results: The mean HRR to a 30 minutes WSRC exergaming session was 69.5 ± 8.3 percent of HRmax with 20 subjects having a mean HRR greater than 64%. Also, ending HR and RPE was significantly greater than starting HR and RPE thereby indicating that the subjects were more fatigued at the end of the exergaming session then they were at the start of it. Conclusions: The mean HRR for subjects for a WSRC 30 minutes exergaming session met the ACSM moderate physical activity intensity guidelines suggesting that playing 30 minutes of WSRC provides a moderate to vigorous aerobic response in above averagely fit males. Practical Application: The results of the current study suggest that people of various fitness levels (i.e., sedentary to fit, team sport athletes, etc.) might have a somewhat similar response to playing WSRC if they were to engage in this exergaming activity. Hence, WSRC may be a viable exercise option for those who seek alternative, yet entertaining ways to meet their daily aerobic activity requirements. Furthermore, it is possible that playing WSRC may serve as another option, yet not a replacement, to upper body ergometry (UBE) for team sport athletes (i.e., soccer, lacrosse, field hockey, etc.) who have a lower body injury and are seeking to either maintain or reduce the severity of decline of their cardiovascular levels until they are able to return to their normal cardiovascular workouts. Further research is needed to determine if increasing the WSRC exergame difficulty level (i.e., from intermediate to expert) or changing the game playing position (i.e., from a seated position to a standing position) may contribute to an even greater cardiovascular training session.

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39. Hyperinflation and Dyspnea During Exercise in Adult Smokers With Chronic Obstructive Pulmonary Disease

K. Brown, S. Sigler, M. Gilbert, K. Hollingsworth, C. Kane, P. Loprinzi, and J. Walker

Bellarmine University

Patients with Chronic Obstructive Pulmonary Disease (COPD) characteristically show chronic hyperinflation or air trapping related to increased end-expiratory lung volume. Hyperinflated lungs can be caused by obstructions in the passages. Air gets trapped within the lung and causes it to overinflate. This limits their inspiratory capacity (IC) or the depth of subsequent inhalation. Lung hyperinflation occurs in some COPD patients at rest, and develops in others during physical activity. However, the degree to which this hyperinflation, coupled with concomitant dyspnea, that occurs during acute exercise among older adults with COPD is relatively unknown. Purpose: The purpose of this study was to evaluate the relationship between IC and perception of dyspnea during acute exercise in older adults with COPD. Specifically, we looked at air trapping-related loss of inspiration depth and self-reported air hunger breathlessness while walking. Methods: Ten participants who were a former or current smoker (60% female; M = 70.1 years) participated in this study. Using the Global Initiative for Chronic Obstructive Lung Disease (GOLD) COPD classification system, 100% of the participants showed moderate to severe COPD severity. Participants completed a 3 stage treadmill test (0% incline) consisting of walking at 2, 2.5, and 3 mph with each stage lasting 5 minutes. Measurements of pulmonary inspiratory capacity were taken. At minute 3 of each stage, participants rated dyspnea using the Multidimensional Dyspnea Profile (MDP). At minute 4 of each stage, 2 to 3 IC measurements were gathered through a portable Wright Respirometer volume-measuring device fitted to the inlet of the Hans-Rudolph valve. Results: The results (mean [SD]) showed during exercise the IC levels across baseline and the 3 stages, respectively, were 1.66 (0.62) L, 1.33 (0.52) L, 1.35 (0.58) L, and 1.28 (0.57) L. The only significant difference occurred between baseline and stage 1 (p = 0.01). The results also showed the dyspnea levels (Likert scale 0–10) across baseline and the 3 stages, respectively, were 0.44 (1.01), 1.44 (2.12), 2.33 (2.59), and 2.67 (2.64). Conclusions: These findings demonstrate that moderate to severe COPD patients are intolerant to low levels of exercise intensity, as demonstrated by reduced IC and increased dyspnea from acute exercise. Practical Application: Exercise physiologists and or respiratory therapists should work together to design effective exercise programs that identify effective strategies to decrease air trapping in COPD patients during low to moderate activity. The physiologist or therapist may need to first focus on increasing the frequency of breaks of sedentary behavior given their (e.g., standing every 20 minutes) intolerance to physical activity. By lowering intolerance to physical activity in the patient may help the physiologist or therapist move the participants to longer durations of physical activity. Future research may want to focus on how to minimize breathlessness in COPD patients by reducing sedentary behavior.

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40. Perceived Exertion and Comfort With Various Clothing Fabrics and Construction During Exercise in the Heat

J. Davis,1 K. Allen,1 and M. Laurent2

1University of Montevallo; and 2Bowling Green State University

Purpose: Manufacturers have marketed sport textiles of synthetic fabrics to have superior properties for keeping wearers cooler, drier, and more comfortable compared to natural fabrics (i.e., cotton). The impact various clothing fabrics and the construction of the fabrics would have on comfort and perceived exertion during exercise in the heat is not well understood. Therefore the purpose of this study was to examine various markers of comfort and perceptual response while exercising in a hot environment with synthetic vs. natural fabrics. Methods: Eight collegiate male athletes completed a treadmill

peak test, and then, in a randomized, counter-balanced order, 3 bouts of 0.60% of

peak (45 minutes total) at 32 °C. Participants wore 3 different t-shirt fabrics during the exercise trial. The fabrics consisted of 100% cotton, 50% cotton and 50% soybean protein fiber, and 100% polyester fiber with large mesh loops to facilitate ventilation through the clothing. Rating of perceived exertion (RPE), thermal sensation, clothing comfort, sweating sensation, and skin wetness were recorded every 5 minutes during the exercise bout. Session RPE (SRPE) and session thermal sensation were recorded following each bout. Results: Repeated measures ANOVA revealed no significant main effect for RPE (p = 0.89), thermal sensation (p = 0.50), sweating sensation (p = 0.18), skin wetness (p = 0.12), or clothing comfort (p = 0.41). There was a significant main effect of clothing condition on SRPE (p = 0.03). Post-hoc measures show that the synthetic clothing condition produced significantly lower SRPE than the cotton clothing (5.8 vs. 6.6; p = 0.04) but not the soy clothing (p = 0.80). There was no difference between cotton and soy (5.8 vs 6.2; p = 0.19). In addition, there was a main effect of clothing condition on overall session thermal sensation reported (p = 0.05) with post-hoc measures showing synthetic clothing produced lower thermal sensation vs. cotton (6.0 vs. 6.6; p = 0.04) but not soy (6.0 vs. 6.2; p = 0.08). There was no significant difference between cotton clothing and soy clothing (p = 0.35). Conclusions: Clothing fabric type or construction of the fiber had no significant effect on perceived exertion or comfort during exercise in the heat. Overall session exertion and thermal sensation was lower with synthetic vs. cotton clothing however no difference between synthetic vs. soy. Practical Application: Although no perceptual advantage is gained from wearing sports textiles during exercise, the use of these fabrics, specifically clothing that allows greater ventilation, may offer potential advantages compared to traditional cotton fabrics based on global perceptual response.

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41. Critical Velocity as a Field Based Estimation OF VO2max in Male Collegiate Soccer Players

C. Fairman,1 K. Kendall,2 S. Rossi,2 P. Hyde,1 M. Yarbough,1 T. Hemmings,1 M. Sherman,1 and D. Fukuda3

1Georgia Southern University-Department of H&K; 2Georgia Southern University; and 3UCF

Soccer is an intermittent sport that utilizes both aerobic and anaerobic systems during a game. Maximal oxygen consumption has been shown to be a significant predictor of performance in soccer players across different skill levels. Laboratory-based determination of oxygen consumption (

) is time consuming and consequently not often used as an evaluation tool in collegiate soccer teams. The critical velocity (CV) test is a unique measure in that it requires less time than individual graded exercise tests for

, and can offer analysis of anaerobic capacity, doubling its utility. Purpose: This study aimed to examine a field-based CV test as a predictor of

in male collegiate soccer players. Methods: Twelve male (mean ± SD, age [year]:19.5 ± 1.2; height [cm]:175.9 ± 7.4; weight [kg]:71.7 ± 10.1) collegiate soccer players were recruited to participate in this study. All players completed a maximal graded running test to exhaustion to determine V02MAX. On a separate day, players completed 3 time-trials at various distances (1200 m, 1800 m, 3200 m) on a outdoor track for the determination of CV and anaerobic running capacity (ARC). Results: A negative, but non-significant correlation was found between ARC and relative

(r = −0.545, p = 0.067). A positive correlation was observed between CV and relative

(r = 0.849, p < 0.001). Based on the significant correlation analysis, a linear regression equation was developed to predict relative

from CV (

= 10.246[CV] + 21.219; SEE = 2.61 ml/kg/min). Conclusions: The positive relationship between CV and

suggests that the CV test may be a practical alternative to measuring maximal oxygen uptake in the absence of a metabolic cart. Practical Application: The proposed field-based method of predicting

is a time-efficient way to predict maximal oxygen consumption, which may be helpful for coaches and athletes when developing a training program. Furthermore, the test also offers a measure of anaerobic capacity, which adds an extra dimension for coaches to evaluate. Additional studies are needed to validate the regression equation and to determine the accuracy of the equation for tracking changes after a training intervention.

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42. Improved Critical Power and Muscle Cross-Sectional Area Following a Progressive 4-Week Cycling Interval Training Program in Men and Women

D. Fukuda,1 J. Stout,1 E. Robinson,2 R. Wang,2 G. Mangine,2 A. Miramonti,2 M. Fragala,2 and J. Hoffman1

1UCF; and 2University of Central FL

The power-time profile of a 3-minute maximal cycling test (3 MT) has been used to estimate critical power (CP), defined as the demarcation point between the heavy and severe exercise intensity domains, and W′, defined as the work capacity available above CP. These parameters have been shown to be augmented in response to high-intensity interval training (HIIT) and related to muscle cross-sectional area (CSA), but their sex-specific responses require further investigation. Purpose: To examine the effects of HIIT on the parameters of the 3 MT and muscle CSA in men and women. Methods: Twenty-five recreationally active men (n = 14; mean ± SD; 24 ± 3 years; 1.79 ± 0.07 m; 82.4 ± 10.7 kg) and women (n = 11; 22 ± 3 years; 1.67 ± 0.08 m; 64.0 ± 8.1 kg) completed testing prior to and following the 4-week training period. All testing and training was conducted using an electronically-braked cycle ergometer. The first day of testing consisted of a graded exercise test (GXT) to determine the power at ventilatory threshold, peak power (PP), and

. During the second day