INTRODUCTION
Numerous studies have been conducted to identify muscle activity during a range of exercises for both the lower body (1,3,10,13,14,16,18) and upper body (2,7,11). In addition, reviews discussing optimal technique of exercises such as the squat (4,5,17) and bench press (9) have been published summarizing the findings of prior research from electromyographic (EMG) studies. However, no such review regarding the performance of the variations of pull-ups or lat pull-downs has been published.
Previous studies investigating lower limb muscle activity during variations of the back squat found that a wide stance width rather than a narrow stance width performed at 0–70% of one repetition maximum (1RM) elicited a 297% greater level of muscle activity for the gluteus maximus, but there were no differences for other lower limb muscles (15). Similarly, an increased squat depth (half squat 45°, parallel squat 90°, full-depth squat 125° knee flexion) resulted in a greater percentage contribution of the gluteus maximus (3,14). In addition, rotating the feet (neutral, 30–40° medial, 80° lateral rotation) while performing the squat, regardless of depth and stance width (75–140% shoulder width), has been shown to have no noticeable effect on muscle activity of the thigh muscles (rectus femoris, vastus medialis, vastus lateralis, adductor longus, semimembranosus, semitendinosus, and biceps femoris) (5,6,13,14,18).
Studies that have investigated EMG activity of upper-body muscles, during the bench press exercise, highlighted no significant effect in activity of the sternocostal head of the pectorialis major (P > 0.05). The narrow grip, however, significantly increased the activity of the clavicular head (P < 0.01) and the activity of the triceps brachii (P < 0.05) compared with the wide grip (2,11). In addition, no significant difference ±5% (P > 0.05) in 1RM performance was identified between grip widths (100 and 200% biacromial width) (2,11). In comparison, performing a push-up with hands posterior to the normal hand position resulted in an increased activation of the pectoralis major and triceps brachii (8).
Previous investigations into the effect that various hand positions, such as grip width and hand orientation (supinated, pronated, and neutral), have on muscle activity during pull-ups and lat pull-downs have demonstrated that both grip width and hand orientation affected muscle activity of selected muscles (11,12,19,21).
HAND ORIENTATION
Youdas et al. (21) found the pronated grip (Figure 1) during pull-ups (56 ± 21% maximum voluntary isometric [MVIC]) to be most effective at activating the lower trapezius compared with the supinated grip (45 ± 22% MVIC). The pronated grip (Figure 2) also resulted in an increased muscle activity of the infraspinatus (79 ± 56% MVIC) compared with the grip of the perfect pull-up (71 ± 52% MVIC), which uses 2 handles with the ability to rotate 360° (the subject starts with a pronated grip then the movement ends with the subject in a supinated grip). In contrast, the perfect pull-up was found to show an increase of muscle activation of the latissimus dorsi (130 ± 53% MVIC) compared with the supinated grip of the chin-up (117 ± 46% MVIC). The supinated grip did elicit an increase in pectoralis major muscle activity (57 ± 36% MVIC versus 44 ± 27% MVIC, respectively) and bicep brachii (96 ± 34% MVIC versus 78 ± 32%, respectively) compared with the pronated variation. It is worth noting that %MVIC for the latissimus dorsi, during each variation of the exercises, was greater than the MVIC for all other muscles assessed.
;)
Figure 1: Close pronated grip hand position.
Figure 2: Supinated grip hand position.
Lusk et al. (12) conducted a study to analyze whether grip width (wide and narrow) and forearm orientation (supinated and pronated grip performed at both grip widths) had any effects on muscle activity during lat pull-downs. Using 70% 1RM, they found that a pronated grip elicited a 9% greater muscle activation of the latissimus dorsi as opposed to a supinated grip. In contrast, they found no difference in biceps brachii or mid-trapezius muscle activity between a supinated or pronated grip. A similar study investigating the differences in muscle activity levels between the wide grip (pulled to the anterior and posterior) and narrow grip (supinated and pronated grip) lat pull-down, by Signorile et al. (19), demonstrated that a pronated grip elicits a higher muscle activation of the latissimus dorsi compared with a supinated grip. The pectoralis major indicated higher muscle activity during the neutral grip compared with the pronated grip; although this is clearly not a pectoral exercise, with Youdas et al. (21) demonstrating pectoral activity of only 44–57% MVIC during various types of pull-ups. The posterior deltoid showed no difference in muscle activity across all hand orientations. In contrast, Lehman (11) investigated the muscle activation levels during the lat pull-downs, using a 10RM load, and little difference was found in the muscle activity between the pronated and supinated grips for the latissimus dorsi and the biceps.
GRIP WIDTH
Lehman (11) found no significant difference in the muscle activation of the biceps and the latissimus dorsi between the narrow supinated grip (Figure 2) and wide pronated grip (Figure 3) lat pull-downs. Interestingly, they did identify that the highest level of latissimus dorsi activity is reached when performing the seated row with the shoulders retracted. Unfortunately, as both hand orientation and grip width were simultaneously altered in this study, any differences in muscle activity due to either grip width or hand orientation are not identifiable. Similarly, Lusk et al. (12) found that grip width, during the lat pull-down, resulted in no difference in latissimus dorsi, biceps brachii, or mid-trapezius muscle activity. However, because the wide grip variation was only slightly wider than the narrow grip variation, it may have masked any minor differences.
Figure 3: Wide grip hand position.
Only the study by Sperandei et al. (20) that has compared the wide grip lat pull-downs with the front and behind neck with a standardized grip width and hand orientation demonstrated higher latissimus dorsi and posterior deltoid muscle activity during lat pull-downs to the front, compared with behind neck. Unfortunately, this study did not compare between grip widths. If individuals are to select the behind neck version of the exercise, it is essential to ensure that the individual has adequate range of motion to perform the exercise safely and effectively throughout the entire range (Tables 1 and 2).
Table 1: Highest muscle activity during variations of pull-ups with different hand orientations
Table 2: Highest muscle activity during variations of lat pull-downs with different hand orientations
It is worth noting that the differences observed between grip widths may be a result of the differences in range of motion which occur between a narrow and wide grip, rather than the actual positioning of the hands.
PRACTICAL APPLICATION
It is suggested that when training the latissimus dorsi using the lat pull-downs a pronated grip be used or rotating handles can be used, if available during pull-ups. A supinated grip, during pull-ups, tends to result in an increase in biceps brachii activity; however, such a hand position may not be specific for certain sports. Further research is required to clarify the effect of grip width on muscle activity lat pull-downs.
REFERENCES
1. Andersen LL, Magnusson SP, Nielsen M, Haleem J, Poulsen K, Aagaard P. Neuromuscular activation in conventional therapeutic exercises and heavy resistance exercises: implications for rehabilitation. Phys Ther 86: 683–697, 2006.
2. Barnett C, Kippers V, Turner P. Effects of variations of the bench press exercise on EMG activity of five shoulder muscles. J Strength Cond Res 9: 222–227, 1995.
3. Caterisano A, Moss RF, Pellinger TK, Woodruff K, Lewis VC, Booth W, Khadra T. The effect of back squat depth on the EMG activity of 4 superficial hip and thigh muscles. J Strength Cond Res 16: 428–432, 2002.
4. Comfort P, Kasim P. Optimizing squat technique. J Strength Cond Res 29: 10–13, 2007.
5. Escamilla RF. Knee biomechanics of the dynamic squat exercise. Med Sci Sports Exerc 33: 127–141, 2001.
6. Escamilla RF, Fleisig GS, Zheng N, Barrentine SW, Wilk KE, Andrews JR. Biomechanics of the knee during closed kinetic chain and open kinetic chain exercises. Med Sci Sports Exerc 30: 556–569, 1998.
7. Glass SC, Armstrong T. Electromyographical activation of the pectorialis muscle during incline and decline bench press. J Strength Cond Res 11: 163–167, 1997.
8. Gouvali MK, Boudolos K. Dynamic and electromyographical analysis in variants of push-up exercise. J Strength Cond Res 19: 146–151, 2005.
9. Green CM, Comfort P. The affect of grip width on bench press
performance and injury risk. Strength Cond J 29: 10–14, 2007.
10. Isear JA Jr, Erickson JC, Worrell TW. EMG analysis of lower extremity muscle recruitment patterns during an unloaded squat. Med Sci Sports Exerc 29: 532–539, 1997.
11. Lehman GJ. The influence of grip width and forearm pronation/supination on upper-body myoelectric activity during the flat bench press. J Strength Cond Res 19: 587–591, 2005.
12. Lusk SJ, Hale BD, Russell DM. Grip width and forearm orientation effects on muscle activity during the lat pull-down. J Strength Cond Res 24: 1895–1900, 2010.
13. McCaw ST, Melrose DR. Stance width and bar load effects on leg muscle activity during the parallel squat. Med Sci Sports Exerc 31: 428–436, 1999.
14. Ninos JC, Irrgang JJ, Burdett R, Weiss JR. Electromyographic analysis of the squat performed in self-selected lower extremity neutral rotation and 30 degrees of lower extremity turn-out from the self-selected neutral position. J Orthop Sports Phys Ther 25: 307–315, 1997.
15. Paoli A, Marcolin G, Petrone N. The effect of stance width on the electromyographical activity of eight superficial thigh muscles during back squat with different bar loads. J Strength Cond Res 23: 246–250, 2009.
16. Schaub PA, Worrell TW. EMG activity of six muscles and VMO: VL ratio determination during a maximal squat exercise. J Sports Rehab 4: 195–202, 1995.
17. Schoenfeld BJ. Squatting kinematics and kinetics and their application to exercise
performance. J Strength Cond Res 24: 3497–3506, 2010.
18. Signorile JF, Kacsik D, Perry A, Robertson B, Williams R, Lowensteyn I, Digel S, Caruso J, LeBlanc WG. The effect of knee and foot position on the electromyographical activity of the superficial quadriceps. J Orthop Sports Phys Ther 22: 2–9, 1995.
19. Signorile JF, Zink AJ, Szwed SP. A comparative electromyographical investigation of muscle utilization patterns using various hand positions during the lat pull-down. J Strength Cond Res 16: 539–546, 2002.
20. Sperandei S, Barros MA, Silveira-Junior PC, Oliveira CG. Electromyographic analysis of three different types of lat pull-down. J Strength Cond Res 23: 2033–2038, 2009.
21. Youdas JW, Amundson CL, Cicero KS, Hahn JJ, Harezlak DT, Hollman JH. Surface electromyographic activation patterns and elbow joint motion during a pull-up, chin-up, or perfect-pullup rotational exercise. J Strength Cond Res 24: 3404–3414, 2010.
