One-On-One

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COLUMN EDITOR: Paul Sorace, MS, RCEP, CSCS* The Biomechanics of the Push-up: Implications for Resistance Training Programs Bret Contreras, MA, CSCS,1 Brad Schoenfeld, MSc, CSCS, NSCA-CPT,2 Jonathan Mike, USAW, CSCS, NSCA-CPT,3 Gul Tiryaki-Sonmez, PhD,4 John Cronin, PhD,5 and Elsbeth Vaino, BS, CSCS6 1Department of Sport Science, Auckland University of Technology, Auckland, New Zealand; 2Department of Exercise Science, Lehman College, Bronx, New York; 3University of New Mexico, Albuquerque, New Mexico; 4Department of Health Science, City University of New York, Lehman College, Queens, New York; 5Sports Performance Research Institute, Auckland University of Technology, Auckland, New Zealand; and 6Ottawa Osteopathy and Sports Therapy, Ottawa, Canada

SUMMARY INTRODUCTION he push-up has long been advo- boxing (22), and martial arts (13), and THE PUSH-UP IS WIDELY USED BY cated as a means to assess local they play a prominent role in the basic FITNESS PROFESSIONALS TO muscular endurance of the upper training programs of the U.S. Military DEVELOP UPPER-BODY T body. A variety of timed and untimed (18). Plyometric push-ups are consid- STRENGTH, POWER, AND LOCAL push-up tests are commonly employed ered essential for optimizing stretch- MUSCULAR ENDURANCE. as part of a fitness assessment, and these shortening cycle–induced adaptations ALTHOUGH THE LOAD DURING A tests have been validated across a wide for the upper body (21). PUSH-UP IS LIMITED BY AN INDI- range of populations (23). Moreover, Although the load during a push-up is VIDUAL’S BODYWEIGHT AND research shows a high correlation limited by an individual’s bodyweight ANTHROPOMETRY, MANY BIOME- between push-up ability and the number and anthropometry, many biomechan- CHANICAL VARIATIONS OF THE of bench press repetitions performed as ical variations of the exercise can be EXERCISE CAN BE PERFORMED. a percentage of body weight (1), thus performed to alter muscle activity by THESE VARIATIONS MAY INVOLVE providing an efficient and inexpensive providing either a lesser or greater ALTERING HAND AND FOOT POSI- alternative to free weight testing. challenge to the target musculature. TIONS, WHICH IMPACTS MUSCLE In fitness settings, push-ups are widely These variations most often involve RECRUITMENT PATTERNS AND used to develop upper-body strength, altering hand and foot positions, which JOINT STRESSES. THE IMPLICA- power, and muscular endurance. They impacts muscle recruitment patterns TIONS OF THESE VARIATIONS MAY are staple exercises in fitness and gym and joint stresses (3,15). Other varia- BE OVERLOOKED WITH RESPECT classes; they are used by strength and tions include using various implements TO THE INDIVIDUAL NEEDS AND conditioning professionals to train such as unstable surfaces, suspension GOALS OF THE CLIENT. athletes in sports such as baseball (10), training devices, and specially designed

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Table 1 Biomechanical data pertaining to the standard push-up

Relative load 69% of bodyweight in top position (2) 75% of bodyweight in bottom position (2) Compressive spinal loading on L4/L5 1,838 N (1) Prime mover mean muscle activation normalized to maximum voluntary contraction Pectoralis major 61% (1) Triceps brachii 66% (1) Anterior deltoid 42% (1) Upper-body stabilizer and synergist muscle activation normalized to maximum voluntary Latissimus dorsi 11% (1) contraction Biceps brachii 4% (1) Posterior deltoid 17% (4) Upper trapezius 45% (3) Middle trapezius 18% (3) Lower trapezius 27% (3) Serratus anterior 56% (3) Core muscle activation normalized to maximum voluntary contraction Psoas 24% (1) External oblique 29% (1) Internal oblique 10% (1) Transverse abdominis 9% (1) Rectus abdominis 29% (1) Rectus femoris 10% (1) Erector spinae 3% (1) push-up equipment. However, the to facilitate glenohumeral range of shoulder width) (9). It is commonly implications of these variations often motion. Table 1 showcases biomechan- believed that the wide base activates are not well understood with respect ical data found in the literature regard- the pectoralis major to a greater degree to the individual needs and goals of ing the standard push-up exercise. than the other positions, whereas the the client. Therefore, the purpose of Push-ups can be performed with a mul- narrow base optimizes the activation of this column is 2-fold: first, to examine titude of variations to bring about dif- the triceps brachii (8). This is consistent the research pertaining to the biome- with the basic principles of applied anat- ferent muscular recruitment patterns. chanical aspects of the push-up; omy. Specifically, the pectoralis major is The knee push-up shortens the lever, second, to make practical recommen- a primary horizontal flexor, and flaring which reduces bodyweight loading to dations for their application to exercise the elbows would seemingly improve 54% in the top position and 62% in the performance. the muscle’s length-tension relationship, bottom position (19) and substantially thereby facilitating its ability to generate reduces prime mover (9) and core mus- THE BIOMECHANICS OF THE greater force (12). On the other hand, culature requirements (11). PUSH-UP a narrow base with the elbows held The standard push-up requires a general Perhaps the most popular variations close to the body would place the pec- stiffening of the knee joints, hip joints, are achieved by altering hand position. torals in a biomechanically disadvanta- pelvis,andspinetokeepthebodyin Although a number of potential hand geous position, thus requiring greater a straight line from head to feet while positions exist, the most common clas- force output from the triceps brachii. the shoulders and elbows flex and sifications include wide base (150% However, electromyographic (EMG) extend to raise and lower the body shoulder width), normal base (shoul- studies evaluating muscle recruitment and the scapulae retract and protract der width), and narrow base (50% patterns during push-up performance

42 VOLUME 34 | NUMBER 5 | OCTOBER 2012 Table 2 Push-up variations for novice, intermediate, and advanced exercisers

Novice variations Wall push-up Torso-elevated push-up Knee push-up Intermediate Standard push-up (figure 1) variations Wide base push-up Narrow base push-up Figure 3. Between-bench push-up. Rapid countermovement push-up Torso-shifted forward push-up suggest that narrow base push-ups not only elicit greater activation of the tri- Torso-shifted rearward push-up ceps brachii compared with the wide Feet-elevated push-up base position but also promote superior activation of the sternal head of the pec- Upper-body suspended push-up (e.g., TRX) (figure 2) toralis major as well (4,9). Hands on stability ball push-up Hands on BOSU ball push-up What is not clear in these studies is Perfect Push-up whether performance was carried out in the transverse plane (i.e., elbows Handle grip push-up flared) or the sagittal plane (i.e., elbow Fall push-up (from knees) close to the body). Contrary to popu- lar belief, when the hands are placed in Staggered base push-up a very narrow position, it tends to Alternating side-to-side push-up encourage flaring of the elbows, orient- ing movement into the transverse One legged push-up plane. If these studies did indeed show Between-bench push-up(figure 3) greater activity of the sternal head in the sagittal plane, further research is Advanced variations Clapping push-up warranted to clarify the reason for this Self-assisted one-arm push-up (figure 4) apparent paradox. Moreover, given that the clavicular head of the pector- One arm push-up alis major is a primary shoulder flexor Weighted-vest push-up (17), it can be theorized that push-ups performed in the sagittal plane would Weighted push-up (plates on back) maximize the activity of this portion of Elastic band-resisted push-up (figure 5) the muscle. To the authors’ knowledge, this has yet to be investigated. Chain push-up (draped over back) (figure 6) In addition, shifting the torso forward or rearward relative to the hands

Figure 2. Upper-body suspended push- Figure 1. Standard push-up. up. Figure 4. Self-assisted one-arm push-up.

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reaction force than all other push- where the unstable surface is the pri- up variations. When expressed as mary base of support. From a muscle a percentage of total body mass, the activation standpoint, it therefore order from least to greatest load pro- appears to be more effective to perform gressed from the hands elevated on exercises such as stability ball and a 61.0-cm box (41% of bodyweight), BOSU push-ups in comparison with tothekneepush-up(49%),tothe stable surface push-ups as long as torso hands elevated on a 30.5-cm box angle remains constant and the hands (55%), to the regular push-up (64%), are placed on the unstable piece of to the feet elevated on a 30.5-cm box equipment rather than the feet. (70%), and finally to the feet elevated Push-ups can also be performed with Figure 5. Elastic band-resisted push-up. on a 61.0-cm box (74%). suspension devices and implements Another push-up variation involves specially designed to facilitate changes affects the muscular recruitment pat- the use of unstable surfaces. Compared in hand positions. Beach et al. (2) terns. Shifting the torso forward relative with standard push-ups, BOSU (Hed- showed that suspended push-ups acti- to the hands results in an increased pec- strom Fitness, Ashland, Ohio) push- vated more core musculature than toralis major activity and a decreased ups have been shown to increase the standard push-ups. One such device, triceps brachii activity compared with activity of some of the scapular stabil- the BOSU Perfect Push-up, is pur- the normal base position. Shifting the izers, namely, the upper, mid, and ported to be biomechanically engi- torso rearward relative to the hands lower trapezius fibers; however serratus neered to achieve better results from results in slightly increased pectoralis anterior activity was diminished (20). push-up workouts. The efficacy of this major and triceps brachii activity (9). Research by Lehman et al. (15) reported claim was investigated by Youdas et al. that elevating the feet above the hands (24) who used EMG to evaluate the Foot position also is often altered to had a greater stimulus on scapulothora- muscle activity in the Perfect Push-up vary muscle recruitment. Recently, cic stabilizing musculature than placing versus standard push-ups. Muscle Ebben et al. (5) assessed the peak ver- the hands on an unstable surface (i.e., activation was evaluated during the tical ground reaction forces of push- stability ball). From a training perspec- performance of push-ups using 3 dif- up variations including the standard tive, it is more challenging and demand- ferent hand positions: normal base, push-up and those performed from ing for the shoulder girdle stabilizers to wide base, and narrow base. The the knees, with feet elevated on perform push-ups with the feet elevated muscles studied included the triceps a 30.5-cm box and a 61.0-cm box, on a bench and the hands on the brachii, pectoralis major, serratus and with hands elevated on these ground than to perform push-ups with anterior, and posterior deltoids. Anal- boxes. Push-ups with the feet ele- the hands on a stability ball and the feet ysis of EMG failed to show any sig- vated produced a higher ground on the ground. nificant differences between the Lehman et al. (14) found that push-ups groups, leading researchers to con- with the hands placed on a stability ball clude that Perfect Push-up handgrips significantly increased the activation of do not seem to increase the muscular triceps brachii. Stability ball push-ups recruitment when compared with the also increased pectoralis major, rectus standard push-ups. abdominis, and external oblique activa- Finally, speed of movement can be tion compared with push-ups on altered to change push-up biomechan- a bench from the same angle, whereas ics. Explosive push-ups have been com- push-ups with the feet placed on a sta- pared in terms of peak force, rate of bility ball did not affect muscle activity force development, and peak impact compared with push-ups with the feet force. Garcia-Masso et al. (7) examined on a bench from the same angle. In the fall push-up (an explosive push-up addition, Marshall and Murphy (16) starting from a tall-kneeling position, showed that triceps brachii and falling to a knee push-up position, and abdominal EMG activity was signifi- returning to the tall-kneeling position), cantly greater when performing push- jump push-up (an explosive push-up ups off stability balls compared with starting from standard position, where stable surfaces from flat and elevated the upper body leaves the ground and positions. These results indicate that becomes airborne before returning to Figure 6. Chain push-up (draped over the stability ball seems to only increase standard position), and countermove- back). the muscle activity during exercises ment push-up (a rapid push-up

44 VOLUME 34 | NUMBER 5 | OCTOBER 2012 characterized by fast eccentric, reversal, progressions and regressions to spine load during various forms of the push-up. and concentric phases but does not achieve desired outcomes. Med Sci Sports Exerc 38: 570–577, 2006. involve leaving the ground) and found 7. Garcia-Masso X, Colado JC, Gonzalez LM, that the countermovement push-up, Salva P, Alves J, Tella V, and Triplett NT. Bret Contreras is a practicing strength which was performed with maximal Myoelectric activation and kinetics of different coach and is currently pursuing his PhD speed, exhibited the highest peak force plyometric push-up exercises. JStrength at AUT University. Cond Res 25: 2040–2047, 2011. and rate of force development. Given that this is the only variation that does 8. Geiger B. Training notebook: Angle play. Brad Schoenfeld is a lecturer in the Muscle Fitness January: 46–48, 2004. not encounter impact forces, it appears exercise science program at CUNY that the countermovement push-up is 9. Gouvali M and Boudolos K. Dynamic and Lehman College and a doctoral student electromyographical analysis in variants of a safe and effective choice for explosive at Rocky Mountain University. push-up exercise. J Strength Cond Res 19: variations if one wishes to maximize the 146–151, 2005. aspects of upper-body power. Clapping Jonathan Mike is a doctoral candidate 10. Hammer C. Preseason training for college push-ups have been shown to outper- baseball. Strength Cond J 31: 79–85, 2009. form standard, slow eccentric, 1 hand in exercise physiology at the University of 11. Juker D, McGill S, Kropf P, and Steffen T. on medicine ball, staggered hands, New Mexico. Quantitative intramuscular myoelectric hands on 2 balls, 2 hands on 1 ball, rapid Gul Tiryaki-Sonmez is an associate activity of lumbar portions of psoas and the countermovement, 1 arm, and alternat- abdominal wall during a wide variety of tasks. ing plyometric push-up variations in professor in the department of health Med Sci Sports Exerc 30: 301–310, 1998. science at CUNY Lehman College and pectoralis major and triceps brachii 12. Kuechle DK, Newman SR, Itoi E, activity (6). Advanced forms of plyo- program director of their exercise science Morrey BF, and An KN. Shoulder muscle metric push-ups could be problematic program. moment arms during horizontal flexion and for individuals with back issues, given elevation. J Shoulder Elbow Surg 6: 429– that an alternating plyometric push-up John Cronin is a Professor in Strength 439, 1997. using a medicine ball has been shown to and Conditioning at AUT University, 13. La Bounty P, Campbell B, Galvan E, induce 6,224 N of compressive forces on NZ and an Adjunct Professor at Edith Cooke M, and Antonio J. Strength and the lumbar spine (6). Cowan University. conditioning considerations for mixed martial arts. Strength Cond J 33: 56–67, 2011. Additional alterations can be employed Elsbeth Vaino is a strength and con- 14. Lehman G, MacMillan B, MacIntyre I, to decrease or increase the challenging ditioning consultant and personal trainer. Chivers M, and Fluter M. Shoulder muscle nature of the exercise. For example, wall EMG activity during push up variations on push-ups (leaning forward with hands and off a Swiss ball. Dyn Med 5: 7, 2006. against the wall) and knee push-ups REFERENCES 15. Lehman G, Gilas D, and Patel U. An (knees on the floor) are appropriate 1. Baumgartner T, Oh S, Chung H, and unstable support surface does not increase for those with limited upper-body Hales D. Objectivity, reliability, and validity scapulothoracic stabilizing muscle activity strength, whereas push-ups using 1 for a revised push-up test protocol. Meas during push up and push up plus exercises. arm or 1 leg can make the movement Phys Educ Exerc Sci 6: 225–242, 2002. Man Ther 13: 500–506, 2008. sufficiently challenging even for those 2. Beach T, Howarth S, and Callaghan J. 16. Marshall P and Murphy B. Changes in who are highly fit. Furthermore, Muscular contribution to low-back loading muscle activity and perceived exertion a weighted vest, elastic bands, chains, and stiffness during standard and during exercises performed on a Swiss ball. Appl Physiol Nutr Metab 31: 376– and/or various unstable implements suspended push-ups. Hum Mov Sci 27: 457–472, 2008. 383, 2006. can be employed to further challenge the upper-body musculature. Table 2 3. Chuckpaiwong B and Harnroongroj T. Palmar 17. Paton ME and Brown JM. 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muscle activity in overhead athletes with strength. J Strength Cond Res 14: 248– push-up for college-age women. Meas symptoms of secondary shoulder 253, 2000. Phys Educ Exerc Sci 8: 203–212, 2004. impingement during closed chain 22. Wallace M and Flanagan S. Boxing: 24. Youdas JW, Budach BD, Ellerbusch JV, exercises. Arch Phys Med Rehabil 91: Resistance training considerations for Stucky CM, Wait KR, and Hollman JH. 550–556, 2010. Comparison of muscle-activation modifying injury risk. Strength Cond J 21: 21. VossenJ,KramerJ,BurkeD,and patterns during the conventional push- 31–39, 1999. Vossen D. Comparison of dynamic push- up and perfect pushup exercises. up training and plyometric push-up 23. Wood H and Baumgartner T. Objectivity, J Strength Cond Res 24: 3352–3362, training on upper body power and reliability, and validity of the bent-knee 2010.

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