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Medicine & Science in Sports & Exercise:
doi: 10.1249/01.mss.0000433610.36179.c2
Abstract

A-35 Free Communication/Poster - Body Composition (Clinical Exercise Physiology Association)

Free Access

May 29, 2013, 7:30 AM - 12:30 PM

Room: Hall C

165 Board #17 May 29, 11:00 AM - 12:30 PM

Student Attitudes Toward Overweight And Obese Individuals: Comfort, Confidence, And Empathy

Christy Greenleaf, Natalie Paly. University of Wisconsin - Milwaukee, Milwaukee, WI. (Sponsor: Heather Chambliss, FACSM)

(No relationships reported)

Health and fitness professionals frequently work with overweight and obese individuals, yet few studies have examined future health professionals’ perceived competence in working with overweight and obese clients in fitness settings.

PURPOSE: To explore associations between three aspects of perceived competence (comfort, confidence, and empathy) with attitudes toward and beliefs about communicating with overweight and obese clients.

METHODS: 162 undergraduate pre-health professionals rated their comfort and confidence in working with overweight and obese clients. Participants also completed an obesity empathy measure, beliefs about personality and physical attributes items, and items regarding beliefs about the importance of communicating a sense of understanding with overweight and obese clients.

RESULTS: Endorsement of attributes believed to be characteristic of overweight and obese individuals were associated with all three aspects of perceived competence. Beliefs that overweight and obese individuals are worthless and unattractive were negatively associated with comfort, confidence, and empathy (r’s between -.20 to -.41); endorsement of unintelligent as a common attribute was negatively associated with comfort (r = -.23) and empathy (r = -.16); endorsement of mentally healthy as a common attribute was positively associated with empathy (r = .17). Communication beliefs regarding the importance of letting clients know that losing weight is difficult were related with comfort and empathy (r = .16 and .18). Empathy was also associated with endorsing the importance of communicating understanding of the physical challenges and complex causes of being overweight, the addictive nature of food and using food as a coping mechanism, what it feels like to be overweight, the psychological concerns of experiencing weight stigma, and the difficulty of being physical active (r’s between .16 to .37).

CONCLUSIONS: Empathy is a particularly salient factor in pre-health professionals’ attitudes toward and beliefs about communicating with overweight and obese clients. Future research should examine empathy as a possible mechanism for buffering weight bias and stigma that is pervasive among health professionals and in health and fitness environments.

166 Board #18 May 29, 11:00 AM - 12:30 PM

Ability of Leg Lean Mass to Predict Maximal Oxygen Consumption in Overweight and Obese Individuals

Rachel M. Graff, Abbie E. Smith-Ryan, Sarah N. Fultz, Malia N. Melvin, Hailee L. Wingfield, Mary N. Woessner. University of North Carolina at Chapel Hill, Chapel Hill, NC.

(No relationships reported)

Maximal oxygen consumption (VO2max) is a strong indicator of cardiorespiratory fitness and overall health. An increased amount of muscle mass, particularly in the legs, has been associated with improvements in health related quality of life. Accounting for leg lean mass when determining VO2max may be advantageous to certain clinical populations. Establishing an alternate way to predict VO2max may reduce risks associated with maximal exercise testing within these populations.

PURPOSE: To examine the ability of leg lean mass, total body lean mass, and body mass to predict VO2max in overweight and obese individuals.

METHODS: Forty-two overweight and obese men and women (mean ± SD; BMI: 31.3 ± 4.7 kgm-2; Age: 38 ± 12 yrs; Ht: 172.1 ± 11.5 cm; Wt: 94.1 ± 15.2 kg) volunteered to participate. Body composition was assessed using a full-body Dual Energy X-Ray Absorptiometry (DEXA, Hologic Discovery W, Bedford, MA) scan to determine a three compartment analysis of body composition (lean mass, fat mass, and bone mineral content) following an 8-hour fast. On a separate lab visit, subjects underwent a graded exercise VO2max assessment using indirect calorimetry (ParvoMedics, Sandy, UT) on an electronically-braked cycle ergometer (Lode, Gronigen, The Netherlands), increasing one watt every three seconds until subjects reached volitional fatigue. Multiple regression using the stepwise method was performed in order to establish the variable(s) accounting for the variance in VO2max.

RESULTS: Leg lean mass averaged 30.1 ± 8.4 kg, total body lean mass averaged 59.2 ± 11.5 kg, and body mass averaged 94.1 ± 15.2 kg. Leg lean mass appeared to be the strongest predictor of VO2max (p < 0.0005), as 76.8% of the variance in VO2max could be explained by leg lean mass (r = 0.877). Standard error of the estimate was 0.368 Lmin-1. VO2max can be predicted by leg lean mass using the following equation VO2max = (0.230 × kg leg lean mass) + 0.078.

CONCLUSIONS: It is possible that utilizing leg lean mass, determined from the DEXA, may be an alternative way to predict VO2max in overweight and obese populations. This strategy may provide a practical way for assessing body composition and cardiovascular health without having to incur the risks associated with maximal exercise testing. Supported by the Nutrition Obesity Research Center (P30DK056350)

167 Board #19 May 29, 11:00 AM - 12:30 PM

Body Mass Percentile Influence on Peak Exercise in Children

Soultana Kourtidou1, Myles Schiller1, Scott Ceresnak2, Christine Walsh2, Gregory Gates2. 1St. Barnabas Hospital, Bronx, NY. 2Children’s Hospital at Montefiore, Bronx, NY.

(No relationships reported)

Obesity has been associated with limited exercise performance in children compared to normal weight individuals.

PURPOSE: To examine the relationship between BMI percentile (BMI%), gender and the cardiopulmonary response to exercise in children.

METHODS: All exercise tests performed at the Children’s Hospital at Montefiore from 2009 - 2012 were retrospectively reviewed. Tests accepted for inclusion utilized the Bruce Protocol treadmill test with breath-to-breath gas exchange and met end of test criteria. Subjects with asthma, congenital heart disease and arrhythmias were excluded in the analysis as were studies performed on the cycle ergometer or studies considered sub-maximal. BMI% was calculated with the CDC-BMI percentile calculator for children and teens. Results are expressed as mean ± SD. ANOVA and linear regression were used for appropriate comparisons with statistical significance set at p ≤ 0.05.

RESULTS: Thirty two subjects, 15 male (m) and 17 female (f) met inclusion criteria. ANOVA suggested there were no gender differences in age (m=13.5±4.0, f=15.8±2.2 years), BMI% (m=79.7±23.9, f=69.1±33.3), peak HR (m=188±12, f=182±8 bpm), peak sysBP (m=164±30, f=150±22 mmHg), RER (m=1.13±0.1, f=1.12±0.1), VE (m=76.0±23.0, f=68.2±16.4), or total exercise time (m=10.6±2.7, f=9.2±2.5 min). Peak VO2ml/kg/min was higher in males (40.6±10.8) compared to females (30.9±7.5; p<0.01). BMI% was predictive of peak VO2ml/kg/min in both male and female subjects (linear regression equation for male: Peak VO2ml/kg/min= 60.5-0.25×BMI%, p<0.04; female: Peak VO2ml/kg/min=40.7-0.14×BMI%, p<0.01). BMI% was not a significant predictor of PeakVO2L/min in either gender.

CONCLUSION: These data suggest that BMI% may predict peak VO2ml/kg/min but not peak VO2L/min. It is therefore important to consider peak oxygen consumption measured in L/min in overweight children as absolute oxygen utilization is not impaired in these individuals. Further study is needed to clearly delineate oxygen consumption through the entire spectrum of body mass percentiles while accounting for body fat percent.

168 Board #20 May 29, 11:00 AM - 12:30 PM

Body Composition Assessment in Overweight Women: Validation of Air Displacement Plethysmography

Hailee L. Wingfield, Abbie E. Smith-Ryan, Mary N. Woessner, Malia N. Melvin, Sarah N. Fultz, Rachel M. Graff. University of North Carolina Chapel Hill, Chapel Hill, NC.

(No relationships reported)

BACKGROUND: An accurate measurement of body composition is important in weight loss and exercise prescription, but the best method is not well determined in overweight women.

PURPOSE: To evaluate the validity and reliability of air displacement plethysmography (ADP) to dual energy x-ray absorptiometry (DXA) criterion for body composition measurement in overweight women.

METHODS: Twenty-four overweight women (BMI range 25.0-45.6 kg•m2; Mean ± SD: 31.3 ± 5.5 kg•m2) (Caucasian and African American; mean ± SD; Age: 36.6 ± 12.0 yrs; Height: 166.4 ± 5.8 cm; Weight: 86.5 ± 14.2 kg; % Body Fat: 38.5 ± 3.7), were tested after an 8-hour fast. Fat mass (FM), fat free mass (FFM), and percent body fat (%BF) were measured by ADP and compared to values determined by the DXA criterion. The reproducibility evaluation included two measurements that were taken 24-48 h apart. A paired samples t-test was used to test for significant differences in the body composition variables between methods. A one-way ANOVA and mean difference scores were used to calculate reliability.

RESULTS: Validity data comparing ADP and DXA demonstrated no significant difference in FM (ADP-DXA FM=0.99 kg; p=0.113) and %BF (1.56 kg; p=0.54), but yielded a significant difference in FFM (1.38 kg; p=0.029). Reliability data for ADP, between the first and second trials showed no significant difference in FM (p=0.168; ICC=0.994; SEM=0.668), FFM (p=0.058; ICC=0.973; SEM=0.892), or %BF (p=0.121; ICC=0.971; SEM=0.813).

CONCLUSIONS: For overweight women, ADP was found to be a valid measure of FM and %BF when compared to DXA. FFM was significantly greater for ADP than the DXA criterion. The reliability of ADP was supported for all body composition variables. Use of ADP for body composition measures in overweight women may be advantageous due to the sensitivity to detect change, it’s validity, and low technician error. ADP may be advantageous to measure changes from a diet or exercise intervention. Supported by the Nutrition Obesity Research Center (P30DK056350).

169 Board #21 May 29, 11:00 AM - 12:30 PM

Correlates of Selecting Bodpod Assessment Among Urban Fitness Center Members

Olivia Smith, Kisha Virgil, NiCole Keith, FACSM. IUPUI, Indianapolis, IN.

(No relationships reported)

Obesity can be monitored through air displacement plethysmography (BodPod). Evaluation of BodPod use among inner-city residents is limited.

PURPOSE: This study compared characteristics of new members of a low-cost inner city fitness center who selected a no-cost BodPod assessment (Users) to those who did not (Non-users).

METHODS: All assessments were optional and also included weight, height, systolic blood pressure (SBP), diastolic blood pressure (DBP), resting heart rate (RHR), body mass index (BMI) and fitness tests (FT). ANOVA and T-tests were used to analyze cross-sectional data.

RESULTS: There were 468 Users and 179 Non-users, 46.2% were Non-Hispanic Black, 45.5% were Non-Hispanic White, and 8% were in the “other” race category. Users were younger (45.22 + 15 vs. 48.30 + 15.4, p<.05), had lower RHR (73.15 + 10.8 vs. 76.76 + 13.2 p < 0.001), SBP (124.34 + 15.0 vs. 125.28 + 14.6, p=0.48), DBP (75.65 +10.7 vs. 77.69 +10.8, p < 0.05), and BMI (32.49 + 9.5 vs. 34.07 +10.5, p=0.07) than non-users. Users generally had higher FT outcomes (chair stands 15.34+5.7 vs. 13.62+4.3, p<0.01; steps 93.15+30.1vs, 86.22+25.4, p<.001; bicepscurls 18.73+5.7 vs. 17.76+5.18, p=0.06) than non-users.

CONCLUSION: In this diverse sample, new members with healthier fitness assessments used the BodPod. Helping less fit new members understand the benefits of knowing their body composition may facilitate improving general health/fitness outcomes. Improving the health/fitness of inner-city residents may aid in achieving health equity.

170 Board #22 May 29, 11:00 AM - 12:30 PM

Validity of Dual Energy X-Ray Absorptiometry for Assessing Body Composition in Overweight and Obese Men and Women

Abbie E. Smith-Ryan, Malia Melvin, Hailee Wingfield, Mary Woessner, Sarah Fultz. University of North Carolina Chapel Hill, Chapel Hill, NC.

(No relationships reported)

Although dual energy x-ray absorptiometry (DXA) has been embraced as a criterion method for body composition assessment, limitations have been identified in normal individuals. It is suggested that those limitations are exacerbated in over-fat individuals.

PURPOSE: To evaluate the accuracy of DXA for measurement of percent body fat (%BF), fat mass (FM), and lean mass (LM) in comparison to a criterion four-compartment (4C) model in overweight men and women.

METHODS:Forty-three participants (Mean ± SD; Age: 37.9 ± 11.8 yrs, Ht: 172.0 ± 11.0 cm, Wt: 93.4 ± 15.4 kg) were measured for body composition, after an 8 hour fast, via DXA (Hologic Discovery W). Estimates of %BF, FM, and LM were compared to a 4C criterion. The Wang-4C model was used: [FM = 2.748(BV) - 0.699(TBW) +1.129(Mo) - 2.051(BM)]; body volume (BV) was measured from air displacement plethysmography, total body water (TBW) from bioelectrical impedance spectroscopy, and total bone mineral content (Mo) derived from the DXA. The validity of DXA to predict body composition was based upon the comparison of predicted values vs. criterion values from the 4C model. Independent samples t-tests were performed to determine significance.

RESULTS: Compared to the 4C model, DXA produced valid results for FM (p=0.138; 30.1 ± 8.8kg vs. 30.8 ± 7.6kg, respectively). Constant error (CE)=0.7kg and standard error of the estimate (SEE)=1.1 kg. Four-C %BF (32.4 ± 8.2%) was significantly different than DXA (33.5 ± 6.9%; p=0.043), with CE=1.2% and SEE=1.4%. LM was also significantly different (p=0.001) when comparing 4C (63.4 ± 14.0kg) to DXA (59.2 ± 11.6kg) with CE=4.2 kg and SEE=2.85 kg. Stratified for sex, male values (n=19) from the DXA produced significantly different values for FM (p=0.039; Δ-1.5 ± 2.8 kg), %BF (p=0.016; Δ-2.2 ± 3.7 kg), and LM (p=0.001; Δ7.1 ± 7.8 kg) compared to the 4C model. For women (n=22), values were significantly different for LM (p=0.018; Δ1.7 ± 3.1 kg), while %BF and FM were not different (p=0.766 and p=0.876, respectively).

CONCLUSIONS: DXA-derived estimations of body composition yielded an

overestimation of %BF and underestimation of LM. These errors hold true for overweight males (26.6-40.1kgm2 BMI), yet more accurate results were reported for women (25.9-45.6 kg•m2 BMI). Supported by Nutrition Obesity Research Center (P30DK056350)

171 Board #23 May 29, 11:00 AM - 12:30 PM

Vo2max Is A Function Of Lean Mass, Not Body Weight - The Dr’S Extra Study

Kai P. Savonen1, Benno Krachler2, Pirjo Komulainen1, Maija Hassinen1, Timo A. Lakka1, Rainer Rauramaa, FACSM1. 1Kuopio Research Institute of Exercise Medicine, University of Eastern Finland, Kuopio, Finland. 2Kuopio Research Institute of Exercise Medicine, Kuopio, Finland.

(No relationships reported)

Maximal oxygen uptake (VO2max) is related to body size. To enable comparison between subjects with varying body masses VO2max is often expressed per unit of total body weight (BW) or lean body mass (LBM). If indexing by BW / LBM is mathematically correct then VO2max of a subject in a particular study sample is predicted by equation VO2max (ml/min) = k x BW / LBM; where the constant k is a sample mean of VO2max (ml/kg/min). The predicted VO2max values can be called BW / LBM -based standard, respectively.

PURPOSE: To compare BW- and LBM-based standards as a body size-independent measure of VO2max.

METHODS: The subjects were a population based sample of 578 men (body mass index [BMI] 19-47 kg/m2) and 592 women (BMI 16-49 kg/m2) 57-78 years of age. Body composition was assessed by bioimpedance and VO2max was assessed by respiratory gas analysis during a maximal exercise stress test on a cycle ergometer. We studied the validity of the BW- and LBM-based standards for prediction of VO2max by comparing them to the actually observed associations of VO2max with BW and LBM by linear regression models. Additionally, we plotted residuals (standard-specific expected VO2max - observed VO2max) against BMI and trends in bias were estimated by linear regression of residuals vs. BMI. Intersections of regression lines’ upper and lower 95% confidence limits with zero were used to define the BMI-interval where estimation of VO2max is not biased by body size. Proportions of individuals within the bias-free BMI-interval were used to compare the BW- and LBM-based standards’ ability to eliminate bias by body size.

RESULTS: The BW-based standard predicted an increase of VO2max with 20.7 ml/min in women and 26.9 ml/min in men per additional kg BW. The observed increase per kg BW was only 8.5 ml/min (95% confidence interval 6.5-10.5) in women and 10.4 ml/min (7.5-13.4) in men. For the LBM-based standard expected and observed increases in VO2max per kg LBM were 32.3 and 34.6 (30.0-39.1) ml/min for women and 36.2 and 37.3 (32.1-42.4) ml/min for men. The BW-based standard was a body size-independent measure of VO2max in 11% of women and 16% of men; corresponding values for the LBM-based standard were 100% and 58%.

CONCLUSION: To eliminate the effect of body size VO2max should not be indexed by BW whereas LBM-based standard serves as a body size-independent measure of VO2max.

172 Board #24 May 29, 11:00 AM - 12:30 PM

Effects of Weight Loss and Maintenance on Hormones Associated with Hunger and Satiety

Justin J. Stout, Joshua S. Wooten, Bryan K. Smith, Jennifer Gapin, Christopher M. Orris, Alissa Yoder, Brendan Graham, Erik P. Kirk. SIUE, Edwardsville, IL.

(No relationships reported)

Weight loss and maintenance may result in a number of hormonal changes that affect the propensity for weight regain.

PURPOSE: To determine changes in hormones associated with hunger (glucose and insulin) and satiety (total peptide YY1-36, peptide YY3-36) in response to 3 months of weight loss and 6 months of weight maintenance treatment.

METHODS: Twenty-five obese (mean±SEM; body mass index BMI; 32.5±1.5 kg/m2; Age; 49.7±2.0 years) adults (M=10, F=15) participated in a 3 month weight loss program that consisted of the American Heart Association’s diet and lifestyle recommendations followed by 6 month of weight maintenance therapy. The weight loss program consisted of a nutritionally balanced diet of pre-packaged meals and shakes (1250-1500 calories/day), weekly healthy lifestyle meetings, and weekly progressive walking recommendations (225 min/week). Fasted blood samples were collected at baseline, 3 and 9 months.

RESULTS: Body weight decreased 10.5±1.5% during the first 3 months and was maintained at 9 months. Glucose decreased (p<0.05) from baseline (103.1±3.9mg/dL) to 3 months (91.2±2.6mg/dL) and was maintained at 9 months (89.8±2.0mg/dL). There was a significant reductions (p<0.01) in insulin from baseline (15.5±2.1μmol/L) to 3 months (10.8±1.9μmol/L) and was maintained at 9 months. PYY3-36 significantly decreased (p<0.05) from baseline to 3 month (-20.1±3.5%) with no further changes at 9 months.

CONCLUSION: Weight loss resulted in the improvement in hormones related to hunger and satiety and were maintained at 9 months suggesting that hormones play a significant role in prevention of weight regain.

173 Board #25 May 29, 11:00 AM - 12:30 PM

Lack of Relationship Between Objectively Determined Sitting Time and Steps/Day in Long-term Post-bariatric Surgery Patients

Ryan ER Reid1, Olivier Babineau1, Tamara E. Carver1, Nicolas V. Christou2, Catrine Tudor-Locke, FACSM3, Ross E. Andersen, FACSM1. 1McGill University, Montreal, QC, Canada. 2McGill University Health Care Center, Montreal, QC, Canada. 3Pennington Biomedical Research Center, Baton Rouge, LA.

(No relationships reported)

Bariatric surgery (BS) is currently the preferred treatment for severe obesity, but little is known about the long-term changes in activity patterns. Logic suggests that time (min/day) spent sitting is time lost accumulating ambulatory activity, or steps/day. This transaction in favor of a positive energy balance may carry important implications for weight maintenance in post-bariatric surgery (PBS) patients.

PURPOSE: To describe 1) min/day in sitting time (ST) and steps/day, and 2) the relationship between these variables in PBS patients.

METHODS: At time of testing, 34 PBS patient volunteers weighed 211.3±53.0 kg with a BMI of 52.4±9.6 kg/m2, reported surgery on average 8.5±3.5 yrs earlier, and had re-gained 22.6±17.7% of their lowest PBS weight loss. Patients were asked to wear a tri-axial accelerometer/inclinometer attached to their mid-thigh for seven consecutive days, 24 hr/day. All patients had ≥5 days of valid data (defined as ≥23 hr/day of wear). Self-reported times for nighttime sleeping facilitated distinguishing this from daytime ST. Descriptive data included steps/day and min/day in ST. The proportion of patients attaining ≥10,000 step/day (a commonly accepted indicator of a physically active lifestyle) was calculated. Spearman rank order correlations were run between steps/day and ST.

RESULTS: The participants averaged 6667±2613 steps/day and 600±119 min/day in ST. Only 12% of PBS patients ≥attained 10,000 steps/day. There was no significant relationship between steps/day and min/day ST (r = -.230, p =.191).

CONCLUSIONS: Although these data were collected on a limited sample, they suggest that time spent sitting during the day is not related to the accumulation of daily steps in PBS patients. Since both physical activity and sedentary behavior are both believed to differentially contribute to energy balance, combined messages to walk more and also sit less may be best for PBS patients.

174 Board #26 May 29, 11:00 AM - 12:30 PM

Accumulation Of Lipid In Old Rats Following Rotator Cuff Tear Is Not Associated With Increases In Canonical Adipogenesis

Jonathan Gumucio, Michael Korn, Anthony Phan, Michael Flood, Stuart Roche, Anjali Saripalli, Evan Lynch, Dennis Claflin, Asheesh Bedi, Christopher Mendias. University of Michigan, Ann Arbor, MI. (Sponsor: John Faulkner, FACSM)

(No relationships reported)

Rotator cuff tears are among the most prevalent disorders of the shoulder in elderly patients. Commonly associated with chronic rotator cuff tears is severe pain and atrophy of the muscle fibers with concomitant fat infiltration, referred to as “fatty degeneration.”

PURPOSE: To gain a greater understanding of the changes in muscle fiber contractility, fiber type distribution and fat accumulation in elderly rats with chronic rotator cuff tears.

METHODS: This study was approved by University of Michigan IACUC. 24-month old male Sprague Dawley rats (N=6) were used, where a unilateral tear of the supraspinatus and infraspinatus were performed and after a period of 30 days, muscles were isolated from both shoulders. The contractility of permeabilized muscle fibers was measured, and force values of torn rotator cuff muscles were compared to the unaffected shoulder. Gene expression was performed using specific primers against various adipogenic, fibrogenic, and inflammatory transcripts. Differences between groups were tested using a Student’s t-test (α=0.05).

RESULTS: Torn rotator cuff muscles exhibited a drastic increase in fat tissue as determined by ORO staining. There was a 28% reduction in specific force (maximum isometric force normalized to fiber CSA) in torn rotator cuff muscles compared to control (P<0.05). Additionally, there was an increase in the expression of PPARγ and C/EBP α (P<0.05), but no significant increases in lipid synthesis or transport genes. Perilipin-1, an important storage protein for large fat globules, was also upregulated following tear (P<0.05). Inflammatory transcripts were upregulated following tear (P<0.05) but no change in the E3 ubiquitin ligase, atrogin-1.

CONCLUSIONS: These results identify chronic structural and molecular changes in an old rat model of torn rotator cuff muscles. Together, the results suggest that, while there is a large increase in fat in the rotator cuff following tear, this accumulation may not be due to canonical adipogenesis within the muscle but rather a pathological accumulation of fat.

175 Board #27 May 29, 11:00 AM - 12:30 PM

Body Composition Comparisons In Overweight And Obese Subjects: Three-compartment Model And Ultrasound Comparisons

Sarah N. Fultz, Abbie Smith-Ryan, Mary Woessner, Rachel Graff, Malia Melvin, Hailee Wingfield, Kelly McDermott. University of North Carolina at Chapel Hill, Chapel Hill, NC.

(No relationships reported)

Background: Identifying valid field methods to measure body composition in overweight and obese individuals is essential for quantifying fat (FM) and fat free mass (FFM) and the associated concomitant health consequences.

PURPOSE: The purpose of this study was to compare the validity of an A-mode ultrasound (US) to the criterion three compartment model (3C) for the measurement of body composition in overweight and obese subjects. Fat mass and FFM were also predicted via the US and 3C model.

METHODS: Forty overweight and obese healthy men and women (mean ± SD; BMI: 32.2 ± 8.2 kg·m2; Age: 38 ± 12 yrs; Ht: 172.1±11.5 cm; Wt: 94.1 ± 15.2 kg) participated in this study. Body composition was measured once via air displacement plethysmography (ADP;BODPOD®, Life Measurements Inc.) for body density (Bd), and bioelectrical impedance spectroscopy (IMPSFB7, Impedimed) for total body water (TBW). The 3C model was used to calculate percent body fat (%BF= [(2.118/Bd - (0.78 × TBW/Body Mass (kg)) - 1.354] × 100). Ultrasound measurements (BodyMetrix, Intelametrix) were also made using an A mode, 2.5- MHz transmitter to determine %BF utilizing the manufacturer’s software. All measurements were made on the right side of the body at 7-sites: chest, subscapular, axilla, tricep, waist, suprailiac and thigh. The 7-site Jackson and Pollock equation was used to determine %BF. Paired samples t-tests were performed to determine significance for %BF, FM, and FFM between the 3C and US values.

RESULTS: The %BF measured by the US (28.3 ± 6.6%) was significantly different from %BF measured via the 3C model (33.1 ± 7.6 %; p < 0.0005). Fat mass measured by the US (26.6 ± 7.5 kg) was significantly different than FM measured by the 3C model (31.0 ± 8.7 kg; p<0.0005) similarly, FFM as measured by the US (67.5 ± 12.9 kg) was significantly different than FFM measured by the 3C model (63.0 ± 13.2 kg; p<0.0005). Discussion: The US was not found to be a valid measurement of body composition in overweight or obese individuals; %BF and FM was significantly under-predicted, while FFM was over-predicted. Although not valid, future studies should examine the reliability of the US due its portability and ease of use.

Supported by the Nutrition Obesity Research Center (P30DK056350).

176 Board #28 May 29, 11:00 AM - 12:30 PM

Changes in Daily Physical Activity Significantly Affect Body Composition in HIV+ Adults Taking Antiretroviral Therapy

Jason R. Jaggers1, Gregory A. Hand, FACSM1, Vivek Prasad1, Xuemei Sui1, Stephanie Burgess1, Wesley D. Dudgeon2, Steven N. Blair, FACSM1. 1University of South Carolina, Columbia, SC. 2The Citadel, Charleston, SC.

(No relationships reported)

Antiretroviral therapy (ART) medications used to treat people living with HIV/AIDS (PLWHA) are associated with toxic side effects, such as lipodystrophy, often resulting in unhealthy changes to body composition. The purpose of this investigation was to examine the effects of changes in physical activity (PA) time on waist circumference and body mass index (BMI) in a sample of HIV+ men and women currently taking ART.

METHODS: Participants were recruited as part of a home-based PA intervention aimed to reduce risk factors of cardiovascular disease for PLWHA taking ART. The intervention consisted of aerobic and resistance exercises completed at home. Theraband® provided elastic bands to all participants to use if needed for strength training. Clinical assessments conducted at baseline and 18 week follow-up included waist circumference, height, weight, and PA levels via accelerometer. Accelerometer data was considered compliant if the participant had a total on-body time of at least 10 hours a day for 4 days. PA was defined as any activity ≥ 3 METS. Changes in PA time from baseline to follow-up were defined as increase (>10 minutes/day), decrease (< -10 minutes/day), and no change (-10 – 10 min).

RESULTS: A total of 20 females and 15 males with valid armband data were used for final data analysis. No significant differences were observed between groups at baseline. Those who increased their PA from baseline to follow-up had an average increase of 34.3 ± 24.5 mins/day and showed a significant decrease in waist circumference (p = 0.001), whereas those who decreased daily PA by an average of 31.2 ± 23 mins/day had a significant increase in waist circumference (p = 0.02) and BMI (p = 0.01). The participants with no changes in PA time showed no change in either variable.

CONCLUSION: These data show that PLWHA can reduce waist circumference by increasing moderate intensity PA, even while on ART. Whereas decreased PA time over an 18 week period significantly increased waist circumference and BMI. In conclusion, PA could be a critical component to self-managing the negative side effects ART has on body composition.

This project was supported by funding through the NIH/NINR R21 Grant 1R21NRO11281 and Theraband®

177 Board #29 May 29, 11:00 AM - 12:30 PM

The accuracy of Bioelectrical Impedance Analysis for Estimating Body Composition in Individuals with Developmental Disabilities

Brett S. Nickerson1, Angela R. Russell1, Christopher T. Jenkins1, Emily Witte1, Ronald D. Snarr1, James K. Taylor1, Alonzo J. Mahurin2, Henry N. Williford, FACSM1, Sara Bicard1, Michael R. Esco1. 1Auburn University at Montgomery, Montgomery, AL. 2Baptist Family Medicine Residency Program, Montgomery, AL.

(No relationships reported)

Individuals with Developmental Disabilities (DD) are at a greater risk of obesity and related chronic related diseases. Thus, predicting body fat percentage (BF%) in this population is important. However, accurate field methods such as bioelectrical impedance analysis (BIA) have not been thoroughly examined in individuals with DD. Most field measures of BF% have been validated using the general population.

PURPOSE: The purpose of this investigation was to cross-validate the hand-to-foot BIA (HF-BIA) for predicting BF% in individuals with DD.

METHODS: Seventeen individuals (15 men and 2 women) with DD (age = 32.3 ± 13.7 years) volunteered to participate in this study. Criterion BF% was determined via dual-energy x-ray absorptiometry (DXA). In addition, BF% was estimated by HF-BIA while the subjects assumed a supine position.

RESULTS: The mean (+/- SD) determined by DXA was 37.6 ± 14.3% and by HF-BIA was 27.0 ± 11.4%. These values were significantly different (p < 0.05). A regression analysis revealed that HF-BIA significantly correlated with DXA (r = 0.77, R2 = 0.60, p < 0.05) with a standard error of estimate ± 9.31%. The constant error (CE) for HF-BIA was -10.5% and revealed limits of agreement of 28.4% below to 7.4% above the DXA.

CONCLUSIONS: This study found that HF-BIA significantly underestimated BF% and provided a large SEE in individuals with DD. Therefore, practitioners should use extreme caution when predicting BF% with HF-BIA in this population. Future research is warranted to develop appropriate field predictors of BF% in individuals with DD.

178 Board #30 May 29, 11:00 AM - 12:30 PM

Comparing Body Fat Distribution in Women According to Weight Perception

Aubrianne E. Rote, Lori A. Klos, Lynn A. Wheeler, Nick C. Thielke, Ann M. Swartz. University of Wisconsin-Milwaukee, Milwaukee, WI. (Sponsor: Leonard Kaminsky, FACSM)

(No relationships reported)

Perception of being overweight is a stronger predictor of women’s weight loss attempts than their actual weight status or diagnosis of a chronic disease. About 13-25% of women perceive themselves to be of normal weight yet have a high % of body fat (BF), which can increase their risk for morbidities related to excess adiposity. Examining contributors to women’s weight perceptions is an important public health agenda.

PURPOSE: To compare distribution of BF in women according to weight perception.

METHODS: 120 women (19.5 ± 1.2 yrs, 31.9 ± 6.8 %BF) self-classified their weight status and had their BF measured using dual-energy x-ray absorptiometry (BF% > 32% was classified as high). Women were categorized into one of three groups: (1) healthy %BF and normal weight perception (Healthy-Normal; n=59), (2) high %BF and normal weight perception (High-Normal; n=25), and (3) high %BF and overweight weight perception (High-Overweight; n=31). One-way ANOVA was used to compare BF distribution in the arms, legs, hips, mid-section, and chest in these groups.

RESULTS: BF% was significantly higher (p < .05) in High-Normal women (36.6%) and High-Overweight women (38.5%) compared to Healthy-Normal women (27.0%). High-Normal women carried 4.3% more of their total BF in their chest (p < .05) and 2.2% less in their hips (p < .05) compared to Healthy-Normal women. High-Normal women carried 0.5% less of their total BF in their android (p < .05) and 1.5% more in their legs (p < .05) compared to High-Overweight women. Compared to Healthy-Normal women, High-Overweight carried 5.6% and 0.9% more of their total BF in their chest (p < .05) and android (p < .05), respectively and 3.0% and 2.9% less in their legs (p < .05) and hips (p < .05), respectively.

CONCLUSION: Among women who had a high %BF but perceived their weight status as normal, fat distribution differed from those with a healthy BF level in just one body region, the chest. Excess BF in the chest is considered desirable in Western societies leading these women to perhaps “discount” this area of body fatness when constructing their weight perception. Additionally, it is unknown to what extent adipose tissue in the chest region contributes to women’s health risk. Future studies examining body fat and weight misperception should consider BF distribution, especially how BF is distributed within the chest.

179 Board #31 May 29, 11:00 AM - 12:30 PM

Comparison of Body Indexes as Surrogates of Whole and Central Body Fat in Nafld Patients

Nuno M. Pimenta1, Helena Santa-Clara2, Helena Cortez-Pinto3, José Silva-Nunes4, Luís B. Sardinha2, Bo Fernhall, FACSM5. 1Sport Science School of Rio Maior - IPS, Rio Maior, Portugal. 2Faculty of Human Kinetics - Technical University of Lisbon, Interdisciplinary Centre for the Study of Human Performance, Cruz Quebrada, Lisboa, Portugal. 3FML, IMM. Hospital Universitário de Santa Maria, Lisboa, Portugal. 4Curry Cabral Hospital, Lisboa, Portugal. 5University of Illinois, Chicago, IL.

(No relationships reported)

Body composition, particularly central body fat (BF), is a major concern in Non-alcoholic Fatty Liver Disease (NAFLD). Body mass index (BMI) limitations are well known and several other body indexes are gaining importance.

PURPOSE: To determine which body indexes are associated with whole BF and central BF in NAFLD patients.

METHODS: Absolut and relative whole BF, trunk BF, abdominal BF (abd BF: measured between the upper edge of L2 and the lower edge of L4) and central abdominal BF (cabd BF: measured as abdominal BF but limited to the lateral sides of rib cage) were assessed with Dual Energy X-ray Densitometry (DXA) in 28 NAFLD patients (19 males, 51 + 13 yrs, and 9 females, 47 + 13 yrs), who were diagnosed through liver biopsy or ultrasound, after exclusion of other potential causes of liver disease. Body indexes included BMI, body adiposity index (BAI = [hip circumference / height^1.5]-18) and Waist to height ratio (WHtR = Waist circumference / height).

RESULTS: Partial correlations showed that, BAI and WHtR were associated with whole BF (r=0.58 and r=0.60, respectively, p<0.01), trunk BF (r=0.56 and r=0.72, respectively, p<0.01), abd BF (r=0.57 and r=0.83, respectively, p<0.01) and cabd BF (r=0.48 and r=0.74, respectively, p<0.01), as well as with whole %BF (r=0.54 and r=0.55, respectively, p<0.01), trunk %BF (r=0.48 and r=0.59, respectively, p<0.05), abd %BF (r=0.44 and r=0.62, respectively, p<0.05), cabd %BF (r=0.51 and r=0.61, respectively, p<0.01) controlled for sex and age. BMI only correlated with whole BF (r=0.65, p<0.001) and trunk BF (r=0.52, p=0.007). Comparison between all coefficients of correlation, using z statistics, showed that all studied body indexes were similarly related to whole BF and trunk BF. However, WHtR was clearly superior to BMI as a surrogate of abdominal BF (p<0.001) and central abdominal BF (p=0.003).

CONCLUSIONS: These body indexes were good surrogates of whole BF and trunk BF and seem suitable for NAFLD patients assessment. Both BAI and WHtR appear to be better alternatives than the widely used BMI, especially when weight measurement is not available. WHtR may be preferable because of its’ superiority in assessing central BF in the present sample of NAFLD patients.

180 Board #32 May 29, 11:00 AM - 12:30 PM

Effects Of Exercise Training On Endothelial Progenitor Stem Cells In Middle-aged Men With Visceral Obesity

Yoo-Chan Kwon1, Jong-Hwan Park2, Jin-Kee Park1, Eun-Hee Kim1, Hyun-Hun Jung1, Joo-Hwa Shin1, Sang-Kab Park1. 1Dong-A University, Busan, Republic of Korea. 2Waseda University, Saitama, Japan.

(No relationships reported)

High-volume visceral fat is a risk factor for atherosclerosis and leads to changes in the physiologic balance of adipokines, insulin resistance, and endothelial dysfunction in middle-aged men. Thus, visceral fat may promote a systemic inflammatory state that affects the development of cardiovascular disease. However, little is known about the relationship between visceral fat and endothelial dysfunction, cellular mechanism throughout exercise training.

PURPOSE: This study was to investigate the effects of a 10-month exercise program on visceral fat and circulating CD34+ stem cells in middle-aged men with visceral obesity.

METHODS: We recruited 45 middle-aged men (age: 40 - 50 years) with visceral obesity. Visceral fat was defined as an abdominal visceral-to-subcutaneous fat ratio ≥ 0.4. The subjects were randomly assigned to 1 of 3 groups: (1) control (n = 15), (2) aerobic (n = 15), or (3) combined (i.e., aerobic + resistance; n = 15). The frequency of exercise for the combined and aerobic groups was 3 times per week (e.g., Monday, Wednesday, and Friday). Each 60-minute exercise program included 10 minutes of warm-up activities and 10 minutes of cool-down activities. In the control group, participants were advised to maintain their normal lifestyle during the study.

RESULTS: For endothelial progenitor cell responses among the control, combined, and aerobic groups, Two-factor ANOVA revealed significant interactions (group × time) for circulating CD34+ stem cells, plasma vascular endothelial growth factor and abdominal visceral fat tissue volume (P = 0.010; P = 0.001; P = 0.034, respectively). Within-group analysis showed that CD34+ stem cells and plasma vascular endothelial growth factor were significantly higher than baseline values in the aerobic group after 10-month (P = 0.034; P = 0.021, respectively).

CONCLUSIONS: The results of this study demonstrated that aerobic exercise program may be an effective intervention strategy for improving vascular repair and visceral fat, leading to improved cardiovascular health in middle-aged men with visceral obesity.

Supported by Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (2010-0023153).

181 Board #33 May 29, 11:00 AM - 12:30 PM

Does Waist-to-height Ratio Predict Cardiometabolic Risk In Obese Adolescents?

Heidi B. IglayReger, Susan J. Woolford, Christine A. Robert, Paul M. Gordon, FACSM. University of Michigan, Ann Arbor, MI.

(No relationships reported)

Obese adolescents are at increased risk for developing diabetes, cardiovascular disease and other cardiometabolic diseases. In a recent cross-sectional assessment of sixth-grade girls, we found that waist circumference was the most significant loading factor in identifying cardiometabolic risk. Waist-to-height ratio has also been suggested as a predictor or risk. These associations have been found in heterogeneous groups.

PURPOSE: To determine if waist:height is associated with cardiometabolic risk in an obese-only mixed gender cohort of adolescents, and to determine if fitness is associated with risk.

METHODS: A fasted blood sample was collected and anthropometric and body composition (air-displacement plethysmography) assessments were completed in obese adolescents entering a family-based weight management program. A subset (n=62) completed VO2 max assessments. Associations were determined via paired, two-tailed Pearson t-tests and deemed significant when p<0.05.

RESULTS: 110 obese adolescents (BMI% 98.9 ± 1.0%; 14 ± 2 years of age; 65% female) completed baseline assessments and were included in analysis. Waist:height, BMI% and adiposity% were positively associated with insulin (r=0.432, 0.378, 0.291), hsCRP (0.351, 0.331, 0.401), and both systolic (0.300, 0.314, 0.229) and diastolic (0.279, 0.364, 0.240) blood pressures (p<0.05 all). Waist:height alone was positively associated with glucose (0.189, p<0.05); BMI% alone was negatively associated with HDL (-0.270) and positively with cholesterol (0.193, p<0.05 all). VO2 max (ml·kg-1·min-1) was negatively associated with hsCRP (-0.376) and positively with waist:height, BMI% and adiposity% (-0.388, -0.407, -0.503, p<0.05 all).

CONCLUSION: Waist:height, BMI% and adiposity% were associated with several cardiometabolic risk factors in obese adolescents, though association strength varied. Future research should determine if changes in waist:height or BMI% predict alterations of cardiometabolic risk in obese adolescents.

182 Board #34 May 29, 11:00 AM - 12:30 PM

Adolescent Strength and Body Composition Changes One Year Post Gastric-Band Surgery

Brittany Couper1, Lauren Falini2, George Datto2, Kirk Reichard2, Melissa Reed1. 1West Chester University, West Chester, PA. 2AI DuPont Hospital for Children, Wilmington, DE.

(No relationships reported)

PURPOSE: To describe body composition and strength changes one year post Gastric-Band surgery in severely obese adolescents.

METHODS: A retrospective chart review was conducted of adolescents who underwent both Gastric-Band surgery and strength testing prior to and one year post-surgery. Muscular strength was measured by hand grip dynamometer with the elbow flexed at 90° using best of two trials. Body composition was measured by bioelectrical impedance analysis with the patient in a supine position. Electrodes were placed on the right wrist, hand, ankle, and foot.

RESULTS: There were 36 patients, aged 14-18 (mean 16.11±1.13), 31 females, 22 Caucasians. 35 patients had pre surgery body composition tests and 18 patients had 1 year post surgery testing. 36 patients had pre surgery strength tests and 17 patients had 1 year post surgery testing. Average weight loss was 18.39±13.04 kg (range -4.6-49.5kg) and percent excess weight loss was 32.64%±19.33% (range -8.87-75.37). 25.56% ± 18.33% of weight lost was FFM. Fat mass (pre: 76.24±15.45, post: 59.43±20.65, P≤0.001), fat-free mass (pre:61.6±17.7, post: 59.5±19.89, P≤0.001), and right hand grip (pre:75.08±13.71, post: 64.76±14.61, P=0.017) significantly decreased one year post-surgery. While left hand grip (pre:68.86±11.81, post:61.82±13.75, P=0.086) did not significantly decrease there was a trend toward a decrease one year post-surgery. Baseline right hand grip strength had a significant positive correlation with fat free mass loss (0.611, p=0.027)

CONCLUSION: Adolescents who had Gastric-Band surgery experienced significant weight loss one year following surgery. There were decreases in both fat mass and fat free mass. Patients who were stronger before surgery lost more fat free mass 1 year after surgery. These results suggest that a decrease in fat-free mass could lead to a decrease in hand grip strength. Further research is needed to determine the most effective strength training prescription to maintain or decrease fat-free loss following surgery.

183 Board #35 May 29, 11:00 AM - 12:30 PM

Leptin and Ghrelin Responses to Maximal Treadmill Exercise in Mexican Adolescents With Different BMI

Maciste H. Macias Cervantes1, Paulina Zarate1, Francisco J. Diaz1, Bernardo A. Ruiz1, Arturo Figueroa, FACSM2. 1Universidad de Guanajuato, LeÃ3n, Mexico. 2The Florida State University, Tallahassee, FL.

(No relationships reported)

PURPOSE:Leptin and ghrelin are two hormones that are positively and negatively related to body mass index (BMI). Previous studies have demonstrated that leptin decreases after aerobic training. However, the responses to a single exercise session are unclear.

PURPOSE: To know the leptin and ghrelin responses to maximal aerobic exercise in adolescents with different BMI.

METHODS:Thirty six adolescents (age 16.3 ± 1.1 y) were divided in 3 groups: normal weight (NW, n=12), overweight (OW, n=12) and obese (O, n=12), according to the IOTF classification. The diet of the subjects was standardized 3 days prior to the exercise test (55% CH, 25%, lipids and 15% proteins). Participants completed a maximal treadmill test using the Balke protocol. Plasma leptin and ghrelin levels were determined before and 2 min after the test.

RESULTS:The proportion of carbohydrates, proteins and lipids were similar in all groups. VO2max tended to be lower in the O group (NW=40.4 ± 8.3, OW= 36.0 ± 5.1, O= 33.9 ± 6.6 ml/kg·min-1, P= 0.07). Leptin and ghrelin baseline and post-exercise levels are presented below. Baseline leptin was higher (*P< 0.05) in the O group than in the NW and OW groups. There were no significant changes in leptin and ghrelin levels after maximal exercise in the three groups. Baseline leptin concentration was correlated with BMI (r= 0.54, P= 0.001) and VO2 max (r= -0.77, P= 0.0001).

CONCLUSIONS:Leptin and ghrelin levels are not altered by maximal treadmill exercise in non-obese and obese adolescents. Our data suggest that high aerobic capacity may have a beneficial effect on resting leptin levels in adolescents. Further studies are needed to examine leptin and ghrelin responses to acute submaximal aerobic and resistance exercise in adolescents.

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184 Board #36 May 29, 11:00 AM - 12:30 PM

Adolescent Cardiovascular Fitness Changes One Year Post Gastric-Band Surgery

Lauren Falini1, George Datto1, Kirk Reichard1, Melissa Reed2. 1AI DuPont Hospital for Children, Wilmington, DE. 2West Chester University, West Chester, PA.

(No relationships reported)

PURPOSE: The purpose of this study was to describe cardiovascular fitness changes one year post Gastric-Band surgery in severely obese adolescents.

METHODS: A retrospective chart review was conducted of patients who underwent both Gastric-Band surgery and maximal fitness testing pre and 1 year post -surgery. A maximal cycle ergometer test was utilized with a 20 watt ramp protocol. Fitness measurements were absolute VO2 (L/min), relative VO2 (ml/kg/min), relative VO2 to fat free mass (FFM) (ml/kg FFM/ min), and maximal work (watts).

RESULTS: There were 21 patients, aged 14-18 (mean 15.8±1.0), 16 females, 15 Caucasians. Average weight loss was 22.05±13.83 kg (range -4.6-49.5kg) and percent excess weight loss was 31.02%±19.08% (range -8.87-75.37). Weight (pre: 145.97 ± 23.70, post: 127.83 ± 23.33, P≤0.001) and BMI (pre: 50.69 ± 8.61, post: 44.40 ± 7.80, P≤0.001) were significantly decreased one year post-surgery. Resting HR (pre:92 ± 14, post: 86 ± 14, P=0.087), max HR (pre: 178 ± 13, post: 182 ± 10, P=0.103) and max blood pressure (pre: 172/63 ± 19/16, post: 161/58 ± 16/12, P=0.139, P=0.119) trended towards a significant decrease and relative VO2 (pre: 19.54 ± 3.56, post: 21.22 ± 4.2, P=0.099) trended towards a significant increase. Maximum absolute VO2 (pre: 2.84 ± 0.5, post: 2.80 ± 0.6, p=0.697), relative VO2 FFM (pre: 45.54± 7.6, post: 46.60 ± 6.5, p=0.658), Watts (pre: 163 ±28.7, post: 167 ± 31.1, p=0.318), and respiratory exchange ratio (pre: 1.1± 0.09, post: 1.1± 0.14, p=0.98) were not significantly different

CONCLUSION: Gastric-band surgery is effective in decreasing weight in adolescent patients. Despite significant weight loss there was not a corresponding significant improvement in cardiovascular fitness. Further research is needed to determine the most effective dose and intensity of exercise in this specific population.

© 2013 American College of Sports Medicine

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