### Abstract
The purpose of this study was to determine the effects of arm span on the acute effects of fatigue caused by maximum voluntary isometric contraction (MVIC) on performance in the bench press. Eight female collegiate track and field athletes involved in the throws events (shot put, discus, hammer, and javelin) volunteered for this investigation. Initial assessments included one-repetition maximums in the bench press (Pre Max 59.5±19.8kg) for each volunteer as well as basic anthropometric data including arm span. Volunteers reported twice for two treatments that included three maximal bench press attempts. The standard (STAND) treatment consisted only of the maximal attempts. The MVIC treatment consisted of a 30-second maximal voluntary isometric contraction prior to maximal attempts. General Linear Model analysis was performed to evaluate fixed effects (Treatment, Arm span) on maximum weight lifted. The model was significant (Likelihood Ratio Chi-Square 3507.525, p<0.001) and revealed main effects for treatment (STAND 59.78±18.8kg vs. MVIC 52.32±11.5kg, p<0.001) and arm span (p<0.001), as well as a significant two-way interaction treatment*arm span (p<0.001). Post-Hoc analysis revealed that under the STAND treatment arm span was not a predictor of change in bench press performance; however under the MVIC treatment (F=16.255, p=0.007) arm span was a significant negative predictor of change in bench press performance (Beta = -0.855, p<0.001). Arm span is a simple measure that can quickly and easily be assessed; yet also a variable that can provide valuable information for coaches to consider before planning weight training for track and field throws athletes.

**Key Words:** Anthropometry, Strength, Athlete

### Introduction
Muscular strength is one essential component contributing to optimal athletic performance (4). The development of upper body strength typically involves high-resistance, low-repetition exercises using larger muscle masses to increase the maximal force generation by a muscle or muscle group. The ability of individuals to adapt positively to increasing training loads requires careful consideration of the volume and intensity of the exercises (1). Regardless of precise planning by the coach, an athlete’s physical limitations may prevent optimal adaptation, or physical gifts may instead promote adaptation (4).

A plethora of anecdotal evidence surrounds the effects of the length of the appendages of the human body on performance in the weight room. In particular in the bench press lift, many recreational lifters maintain that long arm length is detrimental to performance. The fact that lifters with longer arms must displace the bar further from the chest in order to complete the lift would seem to lend some credence to this anecdotal belief. However, recent work by Mayhew et al. (5) demonstrated that skeletal length was not a valid predictor for performance on the NFL-225 bench repetition test. In more recent work, Reynolds et al. (7) examined the relationship between more basic anthropometric measurements and performance in the bench press. In this study, Reynolds et al. recruited seventy subjects, 34 men and 36 women ranging in age from 18-69, and found that no anthropometric measurements were significant predictors on one repetition maximum (1-RM) performance.

Although previous results have not demonstrated a relationship between anthropometric measurements and 1-RM strength, results supporting differences in strength based on skeletal position have been witnessed. Murphy et al. (6) reported a significant correlation between isometric strength at 90 degrees of elbow flexion and 1-RM in the bench press exercise. Interestingly, the participants in this study demonstrated greater isometric strength at 120 degrees of elbow flexion, but this was not related to 1-RM strength. This angle (90 degrees) coincides to the ‘sticking point,’ the point of lowest force production, in the lift (3). It is intuitive that 1-RM strength in the bench press should correlate to the angle of lowest isometric force production. To complete a successful attempt, a lifter must move the weight through the ‘sticking point’ in order to achieve the elbow angle of 120 degrees, a point of greater isometric force production, and from there, finish the lift (3). Lifters who have longer arm spans will thus have a greater total distance to push the bar in order to reach the 120 degrees angle of elbow flexion. Thus, longer arm length could potentially be disadvantageous in the bench press lift.

Although previous research has not demonstrated this disadvantage (5), the Mayhew et al. investigation was descriptive in nature, predicting performance in one predetermined maximal set to failure. Past research evaluating the relationship between arm length and bench press strength has ignored how arm length may affect a total workout. Studies accounting for the potential effects of arm length during fatigue on the bench press are missing from the body of research. It is possible that effects of arm length do not manifest until the lifter is in a fatigued state. Thus, the purpose of the present investigation is to examine, in a very practical way, the effects of arm length on performance in the bench press while fatigued.

### Methods

#### Participants

The present investigation was presented to and approved by the local Institutional Review board for human subject usage. Eight apparently healthy college-aged (19.75yrs±1.2) female track and field athletes who compete in the throws events (shot put, hammer, javelin, discus) volunteered for this study (Table 1). The participants underwent a 1-RM test (Pre Max) for the bench press as prescribed by Baechle and Earle (2) as a normal part of practice and their coach reported their values (59.5kg±19.8).

Table 1. Descriptive Data of the Participants

Conditions Mean±SD
Age (yrs) 19.7±1.2
Height (cm) 171.5±8.7
Weight (kg) 94.7±29.9

*Descriptive data of the (n=8) female participants listed in mean±SD.*

#### Procedures

Participants recruited for the investigation underwent initial anthropometric testing including both height measurement via stadiometer (Health-o-Meter Inc., Bedford, OH.), weight via a balance beam scale (Health-o-Meter Inc., Bedford, OH.), and arm span measured from the farthest distance between finger tips with the arms held outstretched using a vinyl open reel tape measure. Arm span was determined in this manner because it was a simple and inexpensive method of performing an anthropometric assessment of the length of the arms that might also be assessed by a coach with relative ease. The experimental procedures were thoroughly explained to the participants prior the first session. Participants were also given a demonstration on the MVIC device. Grip width was also selected during the initial visit to limit the known effect of different grip widths on the bench press exercise (6). Following the initial visit, participants reported twice more for a total of 30 minutes per session.

##### MVIC induced fatigue

Fatigue was induced in the participants through a 30-second maximum voluntary contraction against a stationary bar set a height equal to 90 degrees of elbow flexion for the participant. The position of the bar was chosen to be approximately at the ‘sticking point’ in order to fatigue at a position critical to the successful completion of the lift. The MVIC device consisted of a standard power rack (York Barbell, York, PA.) with two sets of rails inserted, and a flat bench. A standard Olympic bar (York Barbell, York, PA.) was placed between the rails. The bar was supported from underneath by the lower rail and prevented from being lifted upward by the upper rail; the bar was thus held in a stationary position. The rails were adjustable in height, and the device was set to a point where the elbow of the participant was as close to 90 degrees as the adjustments on the device would allow. Participants were required to lay supine on the bench and press maximally against the Olympic bar for 30 seconds.

#### Experimental Design

The present investigation employed a within subjects design, with random assignment. The participants reported to the weight room on two separate occasions with 72 hours between visits. The sessions occurred at the same time as a normally scheduled team weightlifting session. Each participant was randomly assigned to one of two orders for treatment (STAND then MVIC, or MVIC then STAND).

##### Treatments

Each day began with a standard warm-up on the bench press. The first warm-up set consisted of 5 repetitions of a weight that represented 70% of the previously established one repetition maximum (1-RM). The second warm-up set of three repetitions was done with a weight that represented 80% of 1-RM. Following the warm-up on each day participants completed the protocol for one of two treatments. The first treatment was a standard (STAND) one repetition maximum determination on the bench press. The participants were instructed to attempt a total of three single repetition lifts to determine the maximum amount of weight that could be lifted on that day. The starting weight was set at a value that was approximately 2.25kg underneath the previously determined 1-RM. If the participant successfully completed the attempt they were allowed to increase the weight; if they failed at the attempt approximately 5kg was removed before the second attempt. The second treatment, pre-fatigue via maximum voluntary isometric contraction (MVIC), was identical to STAND except that immediately prior to each attempt the participants performed 30 seconds of MVIC against a stationary bar at approximately 90 degrees of elbow flexion. All participants completed all three attempts under both conditions. At least 3 minutes of recovery were allowed between attempts to reduce between lift fatigue effects (1,7).

#### Statistical Analyses

Prior to analysis all dependant variables were analyzed for normality. Paired samples t-tests were utilized to examine the differences between the two treatments so the degree of pre-fatigue can be determined. Generalized Estimation Equation analysis was utilized to examine the fixed effects of measured arm span on subsequent bench press performance. Any significant interaction effects were further explored via multiple regression analysis. Significance was set a priori at alpha ≥0.05.

### Results

Paired samples t-tests were used to determine the difference between treatments (MVIC vs. STAND). The MVIC treatment resulted in significantly lower performance on the 1-RM test (p=0.02, Table 2). General Linear Model analysis was performed to evaluate fixed effects (Treatment, Arm span) on maximum weight lifted in the bench press. The omnibus test for the model was significant (Likelihood Ratio Chi-Square 3507.525, p<0.001). The analysis revealed main effects for treatment (STAND 59.78±18.8kg vs. MVIC 52.32±11.5kg, p<0.001) and arm span (p<0.001), as well as a significant two-way interaction treatment * arm span (p<0.001). Post-Hoc analysis via linear regression revealed that under the STAND treatment arm span was not a predictor of change in bench press performance as the ANOVA for the model was not significant (F-0.806, p=0.404); however, under the MVIC treatment (F=16.255, p=0.007) arm span was a significant negative predictor of change in bench press performance (Beta = -0.855, p<0.001) (Figure 1).

Table 2. Changes in 1-RM Strength by Treatment

Treatment 1RM post (kg) Change from PreMax Value
MVIC pre-fatigue 53.0±11.5 -6.51±8.56
STAND 60.9±18.8 1.43±2.99

*All values are listed ±SD. 1RM post MVIC and STAND are significantly different p=0.02. Change between MVIC and STAND treatment are significantly different p=0.02.*

### Discussion

Based upon these data it would appear that in a state of induced pre-fatigue, arm span is a significant predictor of 1-RM performance in the bench press for female collegiate track and field throwers. Though previous research has not demonstrated similar findings(5), these findings did not represent data obtained from fatigued subjects. It would appear plausible that the effects of arm span on the bench press may only become manifest in situations of fatigue.

Understanding fatigue is an important consideration for coaches. First, a majority of an athlete’s bench press workouts is a series of sets resulting in muscular fatigue. Secondly, weight-training sessions may occur after a practice has already taken place, ensuring muscular fatigue before the bench press workout begins. Post-exercise fatigue may limit the effectiveness of the resistance-training program as an adaptive physiologic stimulus for strength gains. Understanding how each athlete reacts to fatigue in a workout is imperative to designing a training program in order to achieve maximal strength.

Track and field throws coaches in particular must specifically understand how arm span will affect bench press workouts. Throws coaches often target athletes with longer arms for recruiting purposes; longer levers are advantageous for the discus and hammer events. Coaches training athletes with a greater arm span may have to change bench press protocol to account for a greater fatigue.

The present investigation was not without limitations. Firstly, the choice of measurement of arm span versus actual determination of skeletal lengths was made to increase the applicability of the findings to coaches, but is also a limiting factor. Secondly, the simulated method of fatigue chosen for practicality for the current investigation may not be completely representative of fatigue that occurs as the result of a weight room training session. Though not without limitation, the finding remains that arm span was a significant negative predictor of performance in the pre-fatigued condition.

Future research needs to establish the relationship between arm span and differences in muscle fatigability, and exercise training and prescription in order to optimize strength development in males and females.

### Conclusions

Arm span is a practical measure that can easily be assessed by any coach with access to a tape measure. Fitness professionals and coaches should be aware that in a fatigued state arm span is a negative predictor of performance in the bench press in female track and field throwers. Therefore, it is important for the coach to understand the individual differences among the athletes who are involved in the program; the amount of required recovery time may differ among individuals (4). Considerations for this can be suggested to professionals working with similar athletes including limiting the number of sets performed and focusing on quality of the lifts performed in order to allow for the associated fatigue.

The professional may also want to consider the optimization of the training volume for these athletes based upon the finding that arm span may affect performance in a multiple set lifting scheme. The coach can reduce the number of sets based upon arm span in order to compensate for the increased impact of fatigue that will likely occur for athletes with longer arm spans. For optimizing strength gains, exercise training and prescription to females should be modulated based upon arm span and related to: (1) resistance training to failure versus not to failure; and (2) the effects of a single set versus multiple sets.

### Applications in Sport

Coaches involved in events or sports (i.e. basketball and volleyball) where arm length is a determinant of athletic potential must recognize that these athletes might fatigue to a different degree during weight training than shorter-armed teammates or counterparts. Therefore, it is essential for the coach to understand the individual anthropometric differences among the athletes who are involved in the resistance training program because the amount of required recovery time may differ among individuals. Coaches need to understand this concept in order to get the full strength potential out of their athletes.

### References

Ambdessemed, D. (1999). Effects of recovery duration on muscular power and blood lactate during the bench press exercise. International Journal of Sports Medicine, 20(6), 368-373.

Baechle, T.R., & Earle, R.W. (2008). Essentials of strength training and conditioning (3rd ed.). Champaign: Human Kinetics.

Elliot, B.C., Wilson, G.J., & Graham, K.K. (1989). A biomechanical analysis of the sticking region in the bench press. Medicine & Science in Sports & Exercise, 21(4), 450-462.

Judge, L.W., & Burke, J. (2010). The effect of recovery time on strength performance following a high intensity bench press workout in males and females. International Journal of Sports Physiology and Performance, 5, 184-196.

Mayhew, J.L., Jacques, J.A., Ware, J.S., Chapman, P.P., Bemben, M.G., Ward, T.E., & Slovack, J.P. (2004). Anthropometric dimensions do not enhance one repetition maximum prediction from the NFL-225 test in college football players. Journal of Strength and Conditioning Research, 18(3), 572-582.

Murphy, A.J., Wilson, G.J., Pryor, J.F., Newton, R.U. (1995). Isometric assessment of muscular function: The effect of joint angle. Journal of Applied Biomechanics, 11, 205-215.

Reynolds, J.M., Gordon, T.J., Robergs, R.A. (2006). Predictions of one repetition maximum strength from multiple repetition maximum testing and anthropometry. Journal of Strength and Conditioning Research, 20(3), 584-592.

Wagner, L.L., Evans, S.A., Weir, J.P., Housh, T.J., Johnson, G.O. (1992). The effects of grip width on bench press performance. Journal of Applied Biomechanics, 8(1), 1-10.

### Corresponding Author
Dr. David Bellar
Department of Kinesiology
University of Louisiana at Lafayette
225 Cajundome Blvd
Lafayette, LA 70506
<dmb1527@louisiana.edu>
(216) 374-2590

### Author Bios

David Bellar is an assistant professor and director of the human performance lab in the department of kinesiology at the University of Louisiana at Lafayette. Dr. Bellar has a background in coaching track and field athletes, and researching performance attributes within this population.

Lawrence Judge is an associate professor and coordinator of the graduate coaching program at Ball State University. Dr. Judge has a long-established background in coaching track and field athletes and an extensive research background in coaching behavior, moral issues, and competitiveness versus participation in athletics, specifically in youth sports.

Tiffany Patrick is an undergraduate student studying exercise science in the department of kinesiology at the University of Louisiana at Lafayette.

Erin Gilreath is a graduate assistant studying coaching/sports performance at Ball State University. Erin is the current American record holder in the hammer throw and a 2004 Olympian.