The 1 Repetition Maximum Mechanics of a High-Handle Hexagonal Bar Deadlift Compared With a Conventional Deadlift as Measured by a Linear Position Transducer : The Journal of Strength & Conditioning Research

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Original Research

The 1 Repetition Maximum Mechanics of a High-Handle Hexagonal Bar Deadlift Compared With a Conventional Deadlift as Measured by a Linear Position Transducer

Lockie, Robert G.1,2; Moreno, Matthew R.2; Lazar, Adrina2; Risso, Fabrice G.2; Liu, Tricia M.2; Stage, Alyssa A.2; Birmingham-Babauta, Samantha A.2; Torne, Ibett A.2; Stokes, John J.2; Giuliano, Dominic V.2; Davis, DeShaun L.2; Orjalo, Ashley J.1,2; Callaghan, Samuel J.3

Author Information
Journal of Strength and Conditioning Research: January 2018 - Volume 32 - Issue 1 - p 150-161
doi: 10.1519/JSC.0000000000001781
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Abstract

Introduction

The deadlift, or the conventional deadlift (CD) as it will be referred to in this study, is a popular lower-body focused strength exercise that predominantly targets the leg, hip, back, and torso muscles (14,21,34). This exercise involves the lifter gripping the bar with the hands placed slightly wider than shoulder-width apart in any position (double overhand or mixed grip), and while keeping the arms extended, also extending from the knees and hips (keeping the back straight) to lift the bar from the ground until the legs are straight (20). The effectiveness of the CD within training programs for improving strength has been noted (9,37). However, this exercise can be difficult for some individuals to perform because of physical limitations (21). Body height, relative torso, leg, and arm length, and hip impingements affecting range of motion, can all influence an individual's ability to safely perform the CD (21,22,36). In addition to this, after a review of epidemiology literature, Keogh and Winwood (27) noted that the CD was among the most injury-causing exercises used by powerlifters and strongman athletes. Information such as this supports the need to explore and improve the understanding for alternative forms of the CD, and several variations have been designed that can change the inherent technique of the lift.

One example is the hexagonal bar deadlift (HBD), which is now commonly used in strength training programs (30), and as a resisted jump training tool (40). The hexagonal bar was designed to increase the safety of the exercise irrespective of stature, by allowing the load to be kept closer to the body by creating a barbell frame that the athlete could lift within (6,17,39,40). These bars also come with low or high handles, with the low handles being level with the bar; most research that has investigated the HBD used this bar (6,30,39,40). Swinton et al. (39) detailed that the low-handle HBD (LHBD) reduced vertical bar displacement by approximately 22% when compared with the CD in elite male powerlifters, and the lifters achieved greater knee flexion during the LHBD (39). The moment arm at the lumbar spine was also reduced during the LHBD (39), which could have important implications for the reduction of injury risk when lifting heavy loads in a deadlift-style exercise (27). Malyszek et al. (30) found that the LHBD significantly reduced ankle plantar flexion when compared with the CD, as the lifter needed to extend the lower-limb joints more during the CD as they were positioned behind the bar. Further to these kinematic changes, Camara et al. (6) illustrated that when compared with the CD being lifted with loads of 65 and 85% of 1 repetition maximum (1RM), the LHBD resulted in greater activity of the vastus lateralis in both the concentric and eccentric phases of the lift in strength-trained men. This was related to an increased moment at the knee and reductions in moments at the hip and spine (6,39).

There is much anecdotal information available about using the high-handle HBD (HHBD) (18,22,36), but currently no research investigating their use. Similar to the LHBD, it could be expected that different muscles (e.g., the quadriceps) will be recruited and emphasized within the HHBD (6). It has also been intimated that using the high handles can reduce the range of motion required in the lower-body and the bar displacement (36). If this is the case, the influence on variables such as lift distance and time, as well as peak and mean power, velocity, force, and work during a maximal HHBD lift has yet to be documented. Some context for this is provided by the study conducted by Winwood et al. (45) on the farmers walk exercise. The farmers walk initially involves an individual picking up a heavy load in a manner comparable to the CD, except high handles are used such as those in the HHBD. Using a load equivalent to 70% of 1RM for the CD, Winwood et al. (45) found that when compared with the CD, the farmers walk resulted in greater vertical force and a more vertical trunk during the lift, although the range of motion at the ankle, knees, and hips did not differ between the 2 lifts. The HHBD could also demonstrate differences in a mechanical variable such as force when compared with the CD, although this is yet to be measured in the scientific literature. Furthermore, as peak power and rate of force development were greater in a jump squat performed with a low-handle hexagonal bar because of more favorable load positioning (40), it is possible that power and velocity could be different during the HHBD when compared with the CD. Information about the mechanics of the HHBD would prove most valuable for the strength and conditioning coach, as it could influence how they would program this exercise for their athletes.

The suggested variation in mechanics of the HHBD could also lead to changes in other key variables; for example, the sticking region (SR) within the lift. This term is used to describe the section of a lift where there is a disproportionately large increase in the difficulty to complete the exercise (28), and has been defined as the period from peak barbell velocity until the first local minimum velocity (32,42). However, contrasting views as to how the SR should be defined have been presented in the literature (28). Though it has been suggested that an SR will only occur with lifts above 85% of 1RM (33), Kompf and Arandjelovic (28) asserted that certain individuals could exhibit no load-velocity minimum in certain lifts, and thus no SR. This may occur for the HHBD when compared with the CD. Nonetheless, there has been no analysis of the pattern of a maximal HHBD, let alone whether there is a typical occurrence of an SR in this exercise.

This study, therefore, investigated the mechanics of the HHBD versus that of the CD, during a 1RM lift. Thirty-one strength-trained individuals (21 men, 10 women) were recruited, and performed 1RM lifts for both the CD and HHBD. Each lift was measured via a linear position transducer, which recorded variables such as lift distance (i.e., bar displacement) and duration, power, velocity, force, and work. The use of a linear position transducer to measure each lift was conducted to ensure the data would have a practical value to the strength and conditioning coach, because of the use of this type of equipment within the field (2,5,11,23), and its validity and reliability (4,11,25). The presence of an SR in each lift was also investigated, and whether there were differences between subjects who exhibited an SR and those that did not. It was hypothesized that the duration of the HHBD would be shorter as the bar displacement would be less. However, subjects would lift a higher load in the HHBD because of this change in bar range of movement and the movement pattern itself, which would lead to increases in peak and mean power, velocity, and force when compared with the CD. This would relate to the literature that has acknowledged the biomechanically superior lifting position that can be attained using a hexagonal bar when performing a deadlift-style movement (6,17,30,39,40). It was further hypothesized that the location of any SR for the HHBD and the CD would differ, because of a difference in bar displacement between the lifts. However, whether an SR is present would generally not affect the mechanics of the 1RM CD or HHBD.

Methods

Experimental Approach to the Problem

To compare the differences in the mechanics of the HHBD and CD, a within-subjects crossover design was used for this study. Strength-trained men and women were recruited and performed the 1RM CD and HHBD within 1 testing session, the order of which was randomized. All data were recorded by a linear position transducer for both the CD and HHBD, and the dependent variables included the following: absolute and relative 1RM loads; lift distance and duration; peak and mean power and velocity, and the relative time at which peak power and velocity occurred within the lift; peak and mean force; work; and the presence of an SR, and if so, the duration of the presticking region (PrSR), SR, and poststicking region (PoSR) relative to lift time.

Subjects

Thirty-one strength-trained individuals (Mean +/− SD age = 21–27 years; height = 1.73 ± 0.10 m; body mass = 76.6 ± 16.7 kg), including 21 men (age = 23.5 ± 3.3 years; height = 1.78 ± 0.08 m; body mass = 84.8 ± 13.8 kg) and 10 women (age = 22.6 ± 1.2 years; height = 1.62 ± 0.07 m; body mass = 59.3 ± 7.1 kg), volunteered to participate in this study. Subjects were recruited from the student population at the university. Data were combined for men and women, which has been done in previous maximal strength research studies (3,7,41). Preliminary analysis of the CD and HHBD also indicated similar patterns of lift mechanics within each exercise between the sexes. All subjects were required to be currently in resistance training (≥3 hours per week) with a focus on either hypertrophy or maximal strength development; have a strength-training history (≥2 times per week) of at least 2 years, and be experienced with completing maximal lifts; be experienced with the CD and HHBD; and free from any musculoskeletal disorders that would influence their ability to complete the study. G*Power software (v3.1.9.2; Universität Kiel, Germany) was used to confirm that the sample size of 31 was sufficient for a repeated-measures analysis of variance (ANOVA), within factors analysis, and ensured that the data could be interpreted with a small effect level of 0.15 (24), and a power level of 0.85 when significance was set at 0.05 (15). The California State University, Northridge's ethics committee approved the procedures used in this study. All subjects received a clear explanation of the study, including the risks and benefits of participation, and written informed consent was obtained before testing.

Procedures

Subjects completed 1 testing session, and all assessments were conducted in the teaching gym at the university. Before data collection in the first testing session, the subject's age, height, and body mass were recorded. Height was measured barefoot using a portable stadiometer (seca, Hamburg, Germany). Body mass was recorded by electronic digital scales (Tanita Corporation, Tokyo, Japan). The 1RM for the CD and HBD were both assessed within the 1 session, the procedures of which will be detailed. The exercise that was completed first was randomized among the sample. Subjects refrained from intensive lower-body exercise and maintained a standardized dietary intake in the 24-hour period before testing, and were permitted to consume water as required throughout the testing session. The subjects were free to wear the footwear they were most comfortable in to complete the lifts (i.e., weightlifting shoes or athletic trainers), and the same footwear was worn for both lifts. No knee wraps, weightlifting belts, or other supportive garments were permitted.

Conventional Deadlift and High-Handle Hexagonal Bar Deadlift Maximal Strength Testing

The 1RM was measured for both the CD and HHBD, and the procedures were adapted from Scott et al. (35) and Swinton et al. (39). All lifts were performed on an Olympic lifting platform. The CD was performed with a traditional Olympic bar, whereas the HHBD was performed with a dual height hexagonal bar (American Barbell, San Diego, CA). The distance between the center of the low and high handles was 0.10 m, whereas the distance between the centers of the 2 high handles was 0.64 m. The testing order for the CD and HHBD was randomized among the sample by the randomization function in a Microsoft Excel spreadsheet (Microsoft Corporation, Redmond, WA). The methods here will describe the process if the 1RM for the CD was completed first.

The CD 1RM was performed as described by Graham (20), and subjects were required to maintain a neutral spine throughout the lift (35). Subjects initially completed a general warm-up of 5 minutes cycling on a bicycle ergometer at a self-selected intensity, followed by a dynamic stretching routine that was self-selected and lasted for approximately 10 minutes. Next, 4 specific warm-up sets were completed, with 3 minutes recovery between each set. These sets were composed of 10 repetitions at 50% of 1RM, as estimated by the subject, followed by 5 repetitions at 70% of 1RM, 3 repetitions at 85% 1RM, and 1 repetition at 90% 1RM. After the warm-up sets, the weight increased by approximately 5% and subjects completed a single repetition. This process continued until the subjects were unable to complete a single repetition, with 3 minutes rest provided between attempts. Subjects were instructed to lift the bar with as much force as possible. As defined by Scott et al. (35), a successful repetition was attained when the subject was standing with their shoulders positioned behind the vertical orientation of the bar, which was determined by an investigator positioned adjacent to the subject. This position was attained by the subject extending the knees, retracting the shoulders, and standing erect (39). If the subject did not attain this position, or if the bar was lowered at any point during the ascent (39), the lift was deemed unsuccessful. Subjects could self-select their preferred grip, but were not allowed to use a sumo stance (i.e., the hands had to be positioned outside the legs). No more than 5 attempts were required before the 1RM was attained.

After completion of the 1RM testing for the CD, subjects rested for 10 minutes before attempting the HHBD. The warm-up for the second lift involved completing 3 sets; 5 repetitions at 70% of the estimated 1RM, 3 repetitions at 85% 1RM, and 1 repetition at 90% 1RM. The initial, higher repetition warm-up was foregone in the second exercise as the subjects were already warm from the first exercise (19), and 3 minutes recovery was provided between sets. The same loading procedures that were used for the CD 1RM attempts were also used for the HBD, along with 3 minutes recovery between 1RM attempts. The body position that was required for a successful CD was also required for the HHBD, except that the subject was standing erect within the frame of the hexagonal bar while holding the high handles. As stated, the deadlift testing order was randomized among the sample. Thus, certain subjects performed the HHBD first, followed by the 10-minute break, and then the CD. In addition to the absolute value for both lifts, the 1RM was also scaled relative to body mass according to the formula: .

Data were recorded during each CD and HHBD 1RM attempt by a GymAware Powertool linear position transducer (Kinetic Performance Technology, Canberra, Australia). As described by Drinkwater et al. (12), the GymAware Powertool features a spring-loaded retractable cable that passes around a spool integrated with an optical encoder. The external end of the cable was attached on the inside of the barbell (i.e., inside the plates, and on the outer part of the grip section of the bar) for the CD (Figure 1). For the HHBD, the cable was attached directly underneath the front of the bar (Figure 2). After the manufacturer recommendations, the unit was then placed on the floor directly underneath the bar (12), with the magnetic bottom positioned on top of a weight plate to ensure that it did not move during each lift. The encoder recorded velocity and the movement of the bar at 50 Hz; barbell load was entered into the software to calculate force and power output, for every 3 mm of bar movement (12). The cable provided no additional resistance to the bar. Data for each 1RM attempt were collected and stored on an iPad handheld device (Apple, Inc., Cupertino, CA), before being uploaded to an online database. The data were then exported from this database and entered into Microsoft Excel before statistical analyses.

F1
Figure 1.:
GymAware placement for the conventional deadlift.
F2
Figure 2.:
GymAware placement for the high-handle hexagonal bar deadlift.

A range of variables were measured for the CD and HHBD 1RM that were taken from the GymAware software. These variables included vertical lift distance (i.e., displacement of the bar from lift initiation to lockout) and lift time in seconds. As a maximal deadlift exercise only features a concentric phase (32), only concentric variables were considered. These variables included peak and mean power (watts) and velocity (meters per second), and the relative time (measured as a percentage) when it occurred during the lift; peak and mean force (Newtons); and work (joules). Power, force, and work variables were derived relative to the load on the bar, which was entered into the GymAware software. The GymAware Powertool has been shown to produce reliable and valid data (4,11,25). Black (4) stated that differentiation of displacement data is a valid means of calculating power and force if the initial parameters are accurately measured. To this end, within a validity and reliability analysis of the GymAware Powertool, Black (4) reported typical errors of measurements for a distance of 0.00 m, duration of 0.01–0.02 seconds, and velocity of 0.01 m·s−1. Hori and Andrews (25) reported high and acceptable reliability for peak velocity (coefficient of variation [CV] = 1.1–4.6%) as measured by a countermovement jump, although peak force was less reliable (CV = 4.1–7.9%). Concentric power has been found to have coefficients of variation of 1.0–3.02% across different strength exercises, indicating high reliability (11). Collectively, all variables were considered acceptable for this study.

The power-displacement and velocity-displacement curves of each 1RM lift were analyzed within the software to determine when peak power and velocity occurred within each lift. The velocity-displacement curve was also used to ascertain whether an SR occurred within the 1RM CD or HHBD for each subject. The SR was defined as the period from the first peak barbell velocity until the first local minimum velocity (32,42). Subjects were defined as having an SR if there were 2 clear velocity peaks about a clear decrease in velocity (i.e., the local minimum velocity). The distance covered within 3 separate regions (PrSR, SR, and PoSR) were calculated, as well as the relative duration of each region. Subjects who did not exhibit 2 clear velocity peaks about a dip in velocity (i.e., the bar velocity for these subjects steadily increased until reaching one peak) were defined as not having an SR within the respective 1RM lift (28).

Statistical Analyses

All statistics were computed using the Statistics Package for Social Sciences Version 22.0 (IBM, Armonk, NY). Descriptive statistics (mean ± SD; 95% confidence intervals [CI]) were used to provide the profile for each measured parameter. Several statistical approaches were used in this study. Stem-and-leaf plots were used to ascertain whether there were any outliers in the data for each variable (26,44). Any outliers were treated by a winsorization method (26,29). A repeated-measures ANOVA was used to compare differences in the deadlift variables. This type of analysis was conducted to minimize the chances of making type I errors, and in accordance with this, the criterion for significance was set at p < 0.01 (16). The within-subjects measure (i.e., which deadlift was completed) represented the CD and HHBD conditions. As only 2 repeated measures were employed, the assumption of sphericity, determined by Mauchly's test of sphericity, was not applicable (26). All other repeated-measures ANOVA assumptions were considered. Effect sizes (d) were also calculated for the between-lift comparison, where the difference between the means was divided by the pooled SD (8). A d less than 0.2 was considered a trivial effect; 0.2–0.6 a small effect; 0.6–1.2 a moderate effect; 1.2–2.0 a large effect; 2.0–4.0 a very large effect; and 4.0 and above an extremely large effect (24).

Subjects who did not exhibit an SR in either the CD or the HBD were also compared with those who did for each respective lift. A one-way ANOVA (p < 0.01) was used to derive any differences between these groups for the CD and HHBD, and effect sizes were calculated. Last, those subjects who exhibited an SR in the CD were also compared with those who exhibited an SR in the HHBD. This analysis was conducted to determine whether the distance and relative duration of the 3 regions within the lift (i.e., PrSR, SR, and PoSR) were different between the CD and HHBD. A one-way ANOVA (p < 0.01) was again used, with effect sizes calculated.

Results

The absolute and relative 1RM data are displayed in Table 1, along with the lift distance and duration for the CD and HHBD. There were significant differences for all of these variables between the lifts. The HHBD resulted in a 15% greater absolute (d = 0.46) and relative load (d = 0.70). The vertical lift distance for the HHBD was 22% shorter than that of the CD (d = 1.99), which led to a 25% shorter lift duration (d = 1.14).

T1
Table 1.:
Descriptive statistics (mean ± SD; 95% CI) for absolute and relative strength, lift distance, and lift time for the 1 repetition maximum (1RM) conventional deadlift (CD) and high-handle hexagonal bar deadlift (HHBD) performed with the high handles in strength-trained individuals (n = 31).*

The power, velocity, force, and work characteristics of the CD and HHBD are shown in Table 2. Peak power was 47% significantly greater in the HHBD compared with the CD (d = 1.04), although there was not a significant difference in mean power between the lifts (d = 0.34). Correspondingly, peak velocity was 22% significantly greater in the HHBD (d = 0.81), with no significant difference in mean velocity (d = 0.29). There were no significant differences as to when peak power (d = 0.34) and velocity (d = 0.40) occurred in the CD and HBD. Both peak and mean force were significantly greater in the HHBD compared with the CD, by 20% (d = 0.62) and 22% (d = 0.52), respectively. The CD resulted in a 9% greater amount of work completed during the lift when compared with the HHBD (d = 0.25).

T2
Table 2.:
Peak (PP) and mean (MP) power, time at when peak power occurred in the lift, peak (PV) and mean (MV) velocity, time at when peak velocity occurred in the lift, peak and mean force, and work characteristics (mean ± SD; 95% CI) for the 1 repetition maximum (1RM) conventional deadlift (CD) and hexagonal bar deadlift (HBD) performed with the high handles in strength-trained individuals (n = 31).*

Twenty-one of 31 subjects (68%) did not exhibit an SR in the CD. The velocity profile of an example subject who exhibited an SR in the CD, and one who did not, is shown in Figure 3. When comparing the load, vertical lift distance, lift time (Table 3), and mechanics (Table 4) of the CD between those subjects who exhibited an SR and those that did not, there were no significant differences (d = 0.02–0.83). More subjects also did not exhibit an SR in the HHBD (n = 24; 77%). Figure 4 displays the velocity profile of example subjects who did and did not exhibit an SR in the HBD. There were no significant differences in the HHBD load, lift distance, lift time (Table 5), and mechanics (Table 6) when comparing subjects with or without an SR (d = 0.10–0.78).

F3
Figure 3.:
Velocity profile of an example subject who exhibited a sticking region (SR) in the conventional deadlift (CD) and of a subject who did not.
T3
Table 3.:
Descriptive statistics (mean ± SD; 95% CI) for absolute and relative strength, lift distance, and lift time for the 1 repetition maximum (1RM) conventional deadlift performed by strength-trained individuals with or without a sticking region.*
T4
Table 4.:
Peak (PP) and mean (MP) power, time at when peak power occurred in the lift, peak (PV) and mean (MV) velocity, time at when peak velocity occurred in the lift, peak and mean force, and work characteristics (mean ± SD; 95% CI) for the 1 repetition maximum (1RM) conventional deadlift performed by strength-trained individuals with or without a sticking region.*
F4
Figure 4.:
Velocity profile of an example subject who exhibited a sticking region (SR) in the high-handle hexagonal bar deadlift (HHBD) and of a subject who did not.
T5
Table 5.:
Descriptive statistics (mean ± SD; 95% CI) for absolute and relative strength, lift distance, and lift time for the 1 repetition maximum (1RM) high-handle hexagonal bar deadlift performed by strength-trained individuals with or without a sticking region.*
T6
Table 6.:
Peak (PP) and mean (MP) power, time at when peak power occurred in the lift, peak (PV) and mean (MV) velocity, time at when peak velocity occurred in the lift, peak and mean force, and work characteristics (mean ± SD; 95% CI) for the 1 repetition maximum (1RM) high-handle hexagonal bar deadlift performed by strength-trained individuals with or without a sticking region.*

Figure 5 displays the distances for each region within the CD and HHBD for subjects that displayed an SR. There were no significant differences in the PrSR, SR, or PoSR distances between the lifts. As shown in Figure 6, there were also no significant between-lift differences in the relative duration of the PrSR, SR, or PoSR.

F5
Figure 5.:
Distance covered within each region for those subjects who exhibited a sticking region in the 1 repetition maximum conventional deadlift (CD) or high-handle hexagonal bar deadlift (HHBD). m = meters.
F6
Figure 6.:
Relative duration as a percentage (%) of the lift time in each region for those subjects that exhibited a sticking region in the 1 repetition maximum conventional deadlift (CD) or high-handle hexagonal bar deadlift (HHBD).

Discussion

It has been stated that the HHBD could reduce the range of motion required in the exercise when compared with the CD (36); how this affects the mechanics of the lift have not been defined. Therefore, this study investigated the mechanics of the CD and HHBD in strength-trained individuals. The results indicated that the HHBD reduced the vertical distance the bar was required to travel to reach the lockout position, and the 1RM load that could be lifted was greater for the HHBD compared with the CD. Concurrent with this load increase, peak power, peak velocity, and peak and mean force all increased. Most subjects did not exhibit an SR in the CD or the HHBD. These findings have implications for the strength and conditioning coach, and how they could use an exercise such as the HHBD within their training programs.

In line with the studies' hypothesis, the HHBD resulted in a significantly greater absolute and relative 1RM when compared with the CD. Swinton et al. (39) found that competitive male powerlifters lifted significantly more in the LHBD when compared with the CD (265 ± 41.8 kg vs. 244.5 ± 39.5 kg). However, the results from this study are in contrast to that of Camara et al. (6), who found no differences in the 1RM achieved in a CD and LHBD in strength-trained men (approximately 181 kg for both lifts). The disparity with the 1RM loads from this study to that of Swinton et al. (39) and of Camara et al. (6) would be partially due to the different populations investigated (i.e., male powerlifters vs. strength-trained men vs. strength-trained men and women). Nevertheless, the use of the high handles for the HHBD in the current research would have contributed to the difference seen in load with the CD. As was theorized (36), the HHBD led to a reduction in lift distance and duration compared with the CD. Modifications to the CD can reduce the distance the bar needs to be lifted, which may make the exercise relatively easier to complete and result in a greater load lifted. For example, the sumo deadlift, which is performed with a wider stance and the hands positioned on the bar inside the legs, also resulted in a reduced bar displacement compared with the CD in powerlifters (32). However, most powerlifters still use the CD in competition (32), which suggests other factors would contribute to the greater load lifted in the HHBD. Indeed, a further factor would be the hexagonal bar design that allows the load to be kept closer to the body within the frame (6,17,39,40), and places the individual in a biomechanically superior position for producing the necessary external forces and joint torques to lift a heavy load (39,40). These results indicate that should a strength and conditioning coach prescribe the HHBD, they should do so with the expectation that the individual should lift a heavier load than the CD.

In athletic populations, force and power development are important characteristics to develop and is a focus within strength training programs (1). Thus, strength and conditioning coaches often select exercises that can emphasize force and power specifics to their athletes. The data from this study indicated that the 1RM HHBD resulted in significant increases in peak power, peak velocity, and peak and mean force. This supports the previous research that found that compared with the CD, the LHBD generated greater peak power and velocity at 65 and 85% 1RM in strength-trained men (6), and across loads ranging from 30–80% 1RM in male powerlifters (39). Superior vertical force was demonstrated in a farmers walk that used a high-handled implement when compared with the CD (45), and superior power development was also shown in a jump squat using the LHBD when compared with jump squats using the traditional Olympic bar placement across the shoulders (40). Although the power values recorded in this study were less than that documented by Swinton et al. (39), this would be a function of the different loading schemes that were analyzed (30–80% vs. 100%), as well as the measurement techniques adopted in each study (force plate vs. linear position transducer). These issues notwithstanding, the data recorded from this study have notable implications.

Camara et al. (6) intimated that the LHBD placed the individual in a more advantageous position to generate power, velocity, and force at the start and throughout the lift. Though the high handles were used in this study, it is probable that the current subjects benefited from the lift position required because of the design of the hexagonal bar. In addition to this, the body position attained in a lift such as the HHBD may result in a more upright trunk position that will reduce the torque produced in the lumbar region (39,45). This could potentially allow an individual to lift a heavier load, and generate greater force, while reducing some of the injury risk that has been linked to the CD (27). Future research should incorporate motion capture or a similar type of analysis to confirm any technique changes as a result of the high handles in the HHBD. Nonetheless, the results from this study highlight that when compared with the CD, a maximal HHBD will lead to a greater peak and mean force output, in addition to peak power and velocity.

There were no differences as to the relative time when peak power and velocity occurred within the CD and HHBD after the lift initiation or start time was normalized across the CD and HHBD. This indicates that the time over which the bar is accelerating is similar between the 2 lifts, as power and velocity are increasing throughout this time. Furthermore, similar to Swinton et al. (39), the current data showed that for both the CD and HHBD, the bar was accelerating for most of the lift (approximately 70–75% of the total lift time). Collectively, these results show that the HHBD could be used to emphasize peak power, peak velocity, and peak and mean force. However, the long-term adaptations to the use of the HHBD to develop these capacities are currently unknown. Conventional deadlift training can improve the force and torque generation capacities of college-aged men and women (41). Future research should determine whether this is the case with the HHBD, especially considering the change in the range of motion of the bar shown in this study, as well as the potential differences in lift technique and muscle activation patterns (6,39).

McBride et al. (31) indicated that the total work performed during resistance training sets was the most valid way to monitor strength-training load. This was because work takes into account the force produced during the lift, as well as the displacement of the bar (31). The CD resulted in a greater amount of work performed during the lift, which would relate to the further distance the bar needed to travel. The impact of a reduced bar displacement has been shown in comparisons between the CD and sumo deadlift, with Escamilla et al. (13) detailing that greater mechanical work resulted from the CD. This difference in work could influence how the CD and HHBD exercises are programmed. Although this study only investigated a single repetition, it could be theorized that if there were consistent differences in the work performed across multiple repetitions of the CD and HHBD because of differences in bar displacement, an individual would perform more work with the CD. A greater volume of work during a 6-week strength training program was linked to bench press improvements in trained male junior basketball and soccer players (10). Whether this is the case for the CD and HHBD, and the potential implications on hypertrophy or strength adaptations, needs to be confirmed through future research. Nonetheless, coaches could manipulate the work performed in the HHBD by adjusting the starting position. This may involve using the low handles as per previous research (6,30,39,40), or performing the HHBD on a small box in the same manner as a deficit or platform CD (38). Future research should also measure the work performed during a box or platform HHBD to ascertain whether this is an appropriate way to modify this exercise.

This study also showed that most of the subjects did not exhibit an SR in the 1RM CD (21/31; 68%) or HHBD (24/31; 77%). The deadlift, in its many forms, is a unique exercise in that the lifting phase commences immediately with no eccentric phase (32). This is emphasized within a 1RM deadlift, as there is only a concentric phase. This could have some influence on whether there was an SR for some of the subjects. van den Tillaar et al. (43) found that 5/15 (33%) of their sample did not display an SR in the last repetition of a 6RM free weight squat, so the absence of an SR in lower-body strength exercises are not without precedent. There were also no significant differences between subjects that exhibited an SR and those that did not in the load lifted for the CD or HHBD, the duration and distance of both lifts, and any of the mechanical variables. These results provide support to Kompf and Arandjelovic (28), who suggested that rather than considering the SR as the weak point of the lift, it should be the sticking point that should be noted, as this is the actual point of failure. The presence of an SR may be influenced by the inherent technique of a lifter, which could be why there is greater variation across individuals (28,32). It is outside the scope of this study to confirm these theories as failed lifts of the subjects were not analyzed, nor was the actual lifting technique of the subjects. Nevertheless, the data suggest that regardless of whether an individual exhibits an SR in the CD or HHBD or not, the resulting mechanics will be similar.

The final part of this analysis was to compare those subjects who did exhibit an SR in the CD and HHBD to identify any differences in the PrSR, SR, and PoSR between the 2 lifts. The results indicated that there were no differences in the distances of these regions, nor the relative durations, between the CD and HHBD. Even with the differences in load and bar displacement that occurred, the location of the SR seemed to be similar in both lifts, although the SR SDs for the CD and HHBD also implied a degree of individual variability. McGuigan and Wilson (32) found great variability as to where the SR occurred when comparing the CD and sumo deadlift in elite male powerlifters. The duration of the CD (13.22 ± 9.31%) and HHBD (12.75 ± 9.03%) SR from this research was also much shorter than the CD SR found by McGuigan and Wilson (32) in their sample of powerlifters (37.8 ± 18.2%). The difference in the procedures used (2-dimensional camera vs. linear position transducer), and the fact that the powerlifters lifted a much heavier CD load (215 kg) compared with the subjects from this study who exhibited an SR (CD = 144.53 ± 40.26 kg; HHBD = 138.44 ± 40.15 kg), would have influenced the differences in relative SR duration. Nonetheless, the current findings suggest for those individuals who exhibit an SR in the CD or HBD, the PrSR, SR, and PoSR distance and duration were similar between the lifts.

Although this study provides an initial analysis of the HHBD, there are several limitations that should be noted. This research only used a linear position transducer to measure bar kinematics and kinetics. Although this was done in an attempt to make the data as practical as possible (2,5,11,23), it would be of value to use motion capture and force plates to further analyze the technique of the HHBD. Patterns of muscle activation during the HHBD would also be worthy of investigation, given that the LHBD does cause changes in what muscles are recruited during the lift (6). This would have important training implications, especially considering the increases in load, power, velocity, and force that are present in the HHBD, and what muscles this could be attributed to. This study also only investigated a 1RM lift for both the CD and HHBD. It would also be useful to compare the HHBD and LHBD to ascertain any differences in load, bar mechanics, and technique. Additionally, future research should investigate whether some of the key differences between the exercises (i.e., greater power, velocity, and force in the HHBD; greater work in the CD) are consistent across strength, hypertrophy, and endurance sets. The training adaptations resulting from the long-term use of the HHBD should also be defined.

Within the context of these limitations, the major findings of this study were that when compared with the CD, the HHBD led to a decrease in lift distance and duration during a 1RM and an increase in the load lifted. The HHBD also featured greater peak power and velocity, and peak and mean force. There were no differences in the relative time when peak power and velocity occurred in the CD and HBD, and more work was completed in the CD. Most subjects did not exhibit an SR in the CD or HHBD, and there were no real differences in the load lifted and the mechanics of the CD or HHBD when comparing subjects that did or did not exhibit an SR. Thus, it does not seem that the appearance of an SR is essential for a successful maximal lift for the CD or HHBD.

Practical Applications

There are several practical applications for the strength and conditioning coach that can be drawn from this study. The design of the hexagonal bar which positions the load closer to the lifter, along with the high handles that reduces the displacement of the bar, resulted in a heavier load being lifted in a maximal HHBD compared with a CD. In addition, peak and mean force, as well as peak power and velocity, were greater in the HHBD. For strength and conditioning coaches who wish to emphasize peak and mean force in their athletes, the HHBD could be a good exercise to use in their programs. However, coaches should be cognizant that the long-term training effects of the HHBD, especially considering the reduced range of motion, are yet to be defined. Indeed, a maximal CD resulted in more work being completed than the HHBD. In addition to this, many individuals may not exhibit an SR in a maximal CD or HHBD, although this generally should not impact the resulting load that can be lifted, or variables such as power, velocity, force, and work.

Acknowledgments

The authors would like to acknowledge our subjects for their contribution to this study. They also thank Megan Beiley and Jillian Hurley for assisting with data collection. This research project received no external financial assistance. None of the authors have any conflict of interest.

References

1. Baker D, Nance S, Moore M. The load that maximizes the average mechanical power output during jump squats in power-trained athletes. J Strength Cond Res 15: 92–97, 2001.
2. Ball N, Nolan E, Wheeler K. Anthropometrical, physiological, and tracked power profiles of elite taekwondo athletes 9 weeks before the Olympic competition phase. J Strength Cond Res 25: 2752–2763, 2011.
3. Berning JM, Coker CA, Briggs D. The biomechanical and perceptual influence of chain resistance on the performance of the olympic clean. J Strength Cond Res 22: 390–395, 2008.
4. Black M. Reliability and validity of the GymAware optical encoder to measure displacement data. 2010. Available at: https://kinetic.com.au/pdf/GA-Report2.pdf. Accessed: August 3, 2016.
5. Buttifant D, Hrysomallis C. Effect of various practical warm-up protocols on acute lower-body power. J Strength Cond Res 29: 656–660, 2015.
6. Camara KD, Coburn JW, Dunnick DD, Brown LE, Galpin AJ, Costa PB. An examination of muscle activation and power characteristics while performing the deadlift exercise with straight and hexagonal barbells. J Strength Cond Res 30: 1183–1188, 2016.
7. Cholewicki J, McGill SM, Norman RW. Lumbar spine loads during the lifting of extremely heavy weights. Med Sci Sports Exerc 23: 1179–1186, 1991.
8. Cohen J. Statistical Power Analysis for the Behavioral Sciences (2nd ed.). Hillsdale, NJ: Lawrence Earlbaum Associates, 1988.
9. Crewther BT, Heke TL, Keogh JW. The effects of a resistance-training program on strength, body composition and baseline hormones in male athletes training concurrently for rugby union 7's. J Sports Med Phys Fitness 53: 34–41, 2013.
10. Drinkwater EJ, Lawton TW, Lindsell RP, Pyne DB, Hunt PH, McKenna MJ. Training leading to repetition failure enhances bench press strength gains in elite junior athletes. J Strength Cond Res 19: 382–388, 2005.
11. Drinkwater EJ, Galna B, McKenna MJ, Hunt PH, Pyne DB. Validation of an optical encoder during free weight resistance movements and analysis of bench press sticking point power during fatigue. J Strength Cond Res 21: 510–517, 2007.
12. Drinkwater EJ, Moore NR, Bird SP. Effects of changing from full range of motion to partial range of motion on squat kinetics. J Strength Cond Res 26: 890–896, 2012.
13. Escamilla RF, Francisco AC, Fleisig GS, Barrentine SW, Welch CM, Kayes AV, Speer KP, Andrews JR. A three-dimensional biomechanical analysis of sumo and conventional style deadlifts. Med Sci Sports Exerc 32: 1265–1275, 2000.
14. Farley K. Analysis of the conventional deadlift. Strength Cond J 17: 55–57, 1995.
15. Faul F, Erdfelder E, Lang AG, Buchner A. G*Power 3: A flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behav Res Methods 39: 175–191, 2007.
16. Feise RJ. Do multiple outcome measures require p-value adjustment? BMC Med Res Methodol 2 2002. doi: 10.1186/1471-2288-2-8.
17. Gentry M, Pratt D, Caterisano T. Introducing the trap bar. Strength Cond J 9: 54–56, 1987.
18. Glielmi N. Smarter exercise selection for athletes made simple. 2014. Available at: http://www.stack.com/a/exercise-selection. Accessed: July 12, 2016.
19. Gomo O, Van Den Tillaar R. The effects of grip width on sticking region in bench press. J Sports Sci 34: 232–238, 2016.
20. Graham JF. Exercise: Deadlift. Strength Cond J 22: 18–20, 2000.
21. Hales M. Improving the deadlift: Understanding biomechanical constraints and physiological adaptations to resistance exercise. Strength Cond J 32: 44–51, 2010.
22. Haley A. Exercise of the week: Trap bar deadlift, 2012. Available at: http://www.stack.com/a/exercise-of-the-week-trap-bar-deadlift. Accessed: July 14, 2016.
23. Harris NK, Cronin J, Taylor K-L, Boris J, Sheppard J. Understanding position transducer technology for strength and conditioning practitioners. Strength Cond J 32: 66–79, 2010.
24. Hopkins WG. How to interpret changes in an athletic performance test. Sportscience 8: 1–7, 2004.
25. Hori N, Andrews WA. Reliability of velocity, force and power obtained from the GymAware optical encoder during countermovement jump with and without external loads. J Aust Strength Cond 17: 12–17, 2009.
26. Jeffriess MD, Schultz AB, McGann TS, Callaghan SJ, Lockie RG. Effects of preventative ankle taping on planned change-of-direction and reactive agility performance and ankle muscle activity in basketballers. J Sports Sci Med 14: 864–876, 2015.
27. Keogh JW, Winwood PW. The epidemiology of injuries across the weight-training sports. Sports Med 47: 479–501, 2017.
28. Kompf J, Arandjelovic O. Understanding and overcoming the sticking point in resistance exercise. Sports Med 46: 751–762, 2016.
29. Lien D, Balakrishnan N. On regression analysis with data cleaning via trimming, winsorization, and dichotomization. Commun Stat-Simul C 34: 839–849, 2005.
30. Malyszek KK, Harmon RA, Dunnick DD, Costa PB, Coburn JW, Brown LE. Comparison of Olympic and hexagonal barbells with mid-thigh pull, deadlift, and countermovement jump. J Strength Cond Res 31 :140–145, 2017.
31. McBride JM, McCaulley GO, Cormie P, Nuzzo JL, Cavill MJ, Triplett NT. Comparison of methods to quantify volume during resistance exercise. J Strength Cond Res 23: 106–110, 2009.
32. McGuigan MRM, Wilson BD. Biomechanical analysis of the deadlift. J Strength Cond Res 10: 250–255, 1996.
33. Newton RU, Murphy AJ, Humphries BJ, Wilson GJ, Kraemer WJ, Hakkinen K. Influence of load and stretch shortening cycle on the kinematics, kinetics and muscle activation that occurs during explosive upper-body movements. Eur J Appl Physiol Occup Physiol 75: 333–342, 1997.
34. Piper TJ, Waller MA. Variations of the deadlift. Strength Cond J 23: 66–73, 2001.
35. Scott BR, Slattery KM, Sculley DV, Hodson JA, Dascombe BJ. Physical performance during high-intensity resistance exercise in normoxic and hypoxic conditions. J Strength Cond Res 29: 807–815, 2015.
36. Poloquin Group Editorial Staff. The best deadlift you're not doing. 2015. Available at: http://main.poliquingroup.com/ArticlesMultimedia/Articles/Article/1352/The_Best_Deadlift_Youre_Not_Doing.aspx. Accessed: July 14, 2016.
37. Stock MS, Thompson BJ. Sex comparisons of strength and coactivation following ten weeks of deadlift training. J Musculoskelet Neuronal Interact 14: 387–397, 2014.
38. Swinton PA, Lloyd R, Agouris I, Stewart A. Contemporary training practices in elite British powerlifters: Survey results from an international competition. J Strength Cond Res 23: 380–384, 2009.
39. Swinton PA, Stewart A, Agouris I, Keogh JW, Lloyd R. A biomechanical analysis of straight and hexagonal barbell deadlifts using submaximal loads. J Strength Cond Res 25: 2000–2009, 2011.
40. Swinton PA, Stewart AD, Lloyd R, Agouris I, Keogh JW. Effect of load positioning on the kinematics and kinetics of weighted vertical jumps. J Strength Cond Res 26: 906–913, 2012.
41. Thompson BJ, Stock MS, Shields JE, Luera MJ, Munayer IK, Mota JA, Carrillo EC, Olinghouse KD. Barbell deadlift training increases the rate of torque development and vertical jump performance in novices. J Strength Cond Res 29: 1–10, 2015.
42. van den Tillaar R, Ettema G. The “sticking period” in a maximum bench press. J Sports Sci 28: 529–535, 2010.
43. van den Tillaar R, Andersen V, Saeterbakken AH. The existence of a sticking region in free weight squats. J Hum Kinet 42: 63–71, 2014.
44. Williamson DF, Parker RA, Kendrick JS. The box plot: A simple visual method to interpret data. Ann Intern Med 110: 916–921, 1989.
45. Winwood PW, Cronin JB, Brown SR, Keogh JWL. A biomechanical analysis of the farmers walk, and comparison with the deadlift and unloaded walk. Int J Sports Sci Coach 9: 1127–1143, 2014.
Keywords:

peak and mean force; peak power; peak velocity; sticking region; strength testing; 1RM

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