Volume 7, Issue 4 (Winter 2018)                   PTJ 2018, 7(4): 215-224 | Back to browse issues page

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1- Department of Sport Sciences, Faculty of Educational Science and Psychology, University of Mohaghegh Ardabili, Ardabil, Iran.
2- Department of Sport Biomechanics, Faculty of Humanities, Broojerd Branch, Islamic Azad University, Broojerd, Iran.
3- Department of Pathology and Sport Biomechanics, Faculty of Physical Education and Sport Sciences, Bu-Ali Sina University, Hamadan, Iran.
4- Department of Sports Biomechanics, Faculty of Physical Education and Sports Sciences, University of Mazandaran, Babolsar, Iran.
5- Center for Research in Human Movement Variability, University of Nebraska, Omaha, Nebraska, United States.
Abstract:   (2816 Views)
Purpose: A variation in squatting technique is using arms to actively push the bar up with the upper limbs which is common in bodybuilding. This study aimed to compare the Electromyography (EMG) activity of selected muscles during squat with and without upper limb assistance.
Methods: This was a quasi-experimental study. Fifteen healthy male power lifters (using the convenience sampling method) participated in this study. Participants performed 2 sets of 5 repetitions while squatting 70% of their one-repetition maximum with and without upper limb assistance. Surface EMG signals were collected from 6 muscles using a wireless electromyography with a sampling frequency of 1200 Hz. The paired sample t test was used for statistical analyses at a significance level of P<0.05. The obtained data were analyzed using SPSS. 
Results: Average activity of the gluteus medius during the upward phase of squatting with upper limb assistance increased by 17.1% (P=0.017), compared to squatting without upper limb assistance. Mean activity ratio of the vastus medialis during the downward phase with upper limb assistance showed a 6% decrease (P=0.008). During the downward phase of squatting with upper limb assistance, the mean activity ratio of the vastus medialis to vastus lateralis increased by 15% (P=0.039). During the upward phase with upper limb assistance, the maximum activity of the gluteus medius increased by 22% (P=0.043).
Conclusion: The activity level of the gluteus medius and the activity ratio of the vastus medialis to vastus lateralis increased as a result of squatting with upper limb assistance. This could possibly be helpful in the rehabilitation or prevention of injuries such as patellofemoral pain or iliotibial band friction syndrome. It could also have implications for training variation. 
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Type of Study: Research | Subject: Special
Received: 2017/07/17 | Accepted: 2017/12/3 | Published: 2018/01/1

1. Barton CJ, Kennedy A, Twycross Lewis R, Woledge R, Malliaras P, Morrissey D. Gluteal muscle activation during the isometric phase of squatting exercises with and without a Swiss ball. Physical Therapy in Sport. 2014; 15(1):39-46. [DOI:10.1016/j.ptsp.2013.02.006] [PMID] [DOI:10.1016/j.ptsp.2013.02.006]
2. Powers CM. The influence of abnormal hip mechanics on knee injury: A biomechanical perspective. Journal of Orthopaedic & Sports Physical Therapy. 2010; 40(2):42-51. [DOI:10.2519/jospt.2010.3337] [PMID] [DOI:10.2519/jospt.2010.3337]
3. Prins MR, Van Der Wurff P. Females with patellofemoral pain syndrome have weak hip muscles: A systematic review. Australian Journal of Physiotherapy. 2009; 55(1):9-15. [DOI:10.1016/S0004-9514(09)70055-8] [DOI:10.1016/S0004-9514(09)70055-8]
4. Fredericson M, Cookingham CL, Chaudhari AM, Dowdell BC, Oestreicher N, Sahrmann SA. Hip abductor weakness in distance runners with iliotibial band syndrome. Clinical Journal of Sport Medicine. 2000; 10(3):169-75. [DOI:10.1097/00042752-200007000-00004] [PMID] [DOI:10.1097/00042752-200007000-00004]
5. Bussey MD, Kennedy JE, Kennedy G. Gluteus medius coactivation response in field hockey players with and without low back pain. Physical Therapy in Sport. 2016; 17:24-9. [DOI:10.1016/j.ptsp.2015.03.002] [PMID] [DOI:10.1016/j.ptsp.2015.03.002]
6. Marshall PW, Patel H, Callaghan JP. Gluteus medius strength, endurance, and co-activation in the development of low back pain during prolonged standing. Human Movement Science. 2011; 30(1):63-73. [DOI:10.1016/j.humov.2010.08.017] [PMID] [DOI:10.1016/j.humov.2010.08.017]
7. Noehren B, Davis I, Hamill J. ASB Clinical Biomechanics Award Winner 2006: Prospective study of the biomechanical factors associated with iliotibial band syndrome. Clinical Biomechanics. 2007; 22(9):951-6. [DOI:10.1016/j.clinbiomech.2007.07.001] [PMID] [DOI:10.1016/j.clinbiomech.2007.07.001]
8. Dierks TA, Manal KT, Hamill J, Davis IS. Proximal and distal influences on hip and knee kinematics in runners with patellofemoral pain during a prolonged run. Journal of Orthopaedic & Sports Physical Therapy. 2008; 38(8):448-56. [DOI:10.2519/jospt.2008.2490] [PMID] [DOI:10.2519/jospt.2008.2490]
9. Willson JD, Davis IS. Lower extremity mechanics of females with and without patellofemoral pain across activities with progressively greater task demands. Clinical Biomechanics. 2008; 23(2):203-11. [DOI:10.1016/j.clinbiomech.2007.08.025] [PMID] [DOI:10.1016/j.clinbiomech.2007.08.025]
10. Souza RB, Powers CM. Differences in hip kinematics, muscle strength, and muscle activation between subjects with and without patellofemoral pain. Journal of Orthopaedic & Sports Physical Therapy. 2009; 39(1):12-9. [DOI:10.2519/jospt.2009.2885] [PMID] [DOI:10.2519/jospt.2009.2885]
11. Smith T, Chester R, Cross J, Hunt N, Clark A, Donell S. Rehabilitation following first-time patellar dislocation: A randomised controlled trial of purported vastus medialis obliquus muscle versus general quadriceps strengthening exercises. The Knee. 2015; 22(4):313-20. [DOI:10.1016/j.knee.2015.03.013] [PMID] [DOI:10.1016/j.knee.2015.03.013]
12. Husted RS, Bencke J, Andersen LL, Myklebust G, Kallemose T, Lauridsen HB, et al. A comparison of hamstring muscle activity during different screening tests for non-contact ACL injury. The Knee. 2016; 23(3):362-6. [DOI:10.1016/j.knee.2016.02.004] [PMID] [DOI:10.1016/j.knee.2016.02.004]
13. Pellicer-Chenoll M, Serra Aó P, Cabeza-Ruiz R, Pardo A, Aranda R, González L. Comparison of conventional hamstring/quadriceps ratio between genders in level-matched soccer players. Revista Andaluza de Medicina del Deporte. 2017; 10(1):14-8. [PMID] [PMCID] [DOI:10.1016/j.ramd.2015.05.002]
14. Bryant A, Newton R, Bronks R, Randle R. Activation of the quadriceps and hamstrings during isokinetic knee extension with ACL deficiency and following reconstruction using either the patella or hamstring tendon grafts. Journal of Science and Medicine in Sport. 2002; 5(4):65-7. [DOI:10.1016/S1440-2440(02)80165-7] [DOI:10.1016/S1440-2440(02)80165-7]
15. Distefano LJ, Blackburn JT, Marshall SW, Padua DA. Gluteal muscle activation during common therapeutic exercises. Journal of Orthopaedic & Sports Physical Therapy. 2009; 39(7):532-40. [DOI:10.2519/jospt.2009.2796] [PMID] [DOI:10.2519/jospt.2009.2796]
16. Hewett TE, Myer GD, Ford KR. Anterior cruciate ligament injuries in female athletes part 1, mechanisms and risk factors. The American Journal of Sports Medicine. 2006; 34(2):299-311. [DOI:10.1177/0363546505284183] [PMID] [DOI:10.1177/0363546505284183]
17. Biscarini A, Contemori S, Busti D, Botti FM, Pettorossi VE. Knee flexion with quadriceps cocontraction: A new therapeutic exercise for the early stage of ACL rehabilitation. Journal of Biomechanics. 2016; 49(16):3855-60. [DOI:10.1016/j.jbiomech.2016.10.026] [PMID] [DOI:10.1016/j.jbiomech.2016.10.026]
18. Faul F, Erdfelder E, Lang AG, Buchner A. G*Power 3: A flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behavior Research Methods. 2007; 39(2):175-91. [DOI:10.3758/BF03193146] [PMID] [DOI:10.3758/BF03193146]
19. Cotterman ML, Darby LA, Skelly WA. Comparison of muscle force production using the Smith machine and free weights for bench press and squat exercises. The Journal of Strength & Conditioning Research. 2005; 19(1):169-76. [DOI:10.1519/14433.1] [DOI:10.1519/14433.1]
20. Walker S, Peltonen H, Avela J, Häkkinen K. Kinetic and electromyographic analysis of single repetition constant and variable resistance leg press actions. Journal of Electromyography and Kinesiology. 2011; 21(2):262-9. [DOI:10.1016/j.jelekin.2010.12.004] [PMID] [DOI:10.1016/j.jelekin.2010.12.004]
21. Hermens HJ, Freriks B, Merletti R, Stegeman D, Blok J, Rau G, et al. European recommendations for surface electromyography. Roessingh Research and Development. 1999; 8(2):13-54.
22. Semciw AI, Neate R, Pizzari T. A comparison of surface and fine wire EMG recordings of gluteus medius during selected maximum isometric voluntary contractions of the hip. Journal of Electromyography and Kinesiology. 2014; 24(6):835-40. [DOI:10.1016/j.jelekin.2014.08.015] [PMID] [DOI:10.1016/j.jelekin.2014.08.015]
23. Vera Garcia FJ, Moreside JM, McGill SM. MVC techniques to normalize trunk muscle EMG in healthy women. Journal of Electromyography and Kinesiology. 2010; 20(1):10-6. [DOI:10.1016/j.jelekin.2009.03.010] [PMID] [DOI:10.1016/j.jelekin.2009.03.010]
24. Heiden TL, Lloyd DG, Ackland TR. Knee joint kinematics, kinetics and muscle co-contraction in knee osteoarthritis patient gait. Clinical Biomechanics. 2009; 24(10):833-41. [DOI:10.1016/j.clinbiomech.2009.08.005] [PMID] [DOI:10.1016/j.clinbiomech.2009.08.005]
25. Cowan S. The role of gluteus medius in patellofemoral pain. Journal of Science and Medicine in Sport. 2006; 9:6. [DOI:10.1016/j.jsams.2006.12.010] [DOI:10.1016/j.jsams.2006.12.010]
26. Ott B, Cosby NL, Grindstaff TL, Hart JM. Hip and knee muscle function following aerobic exercise in individuals with patellofemoral pain syndrome. Journal of Electromyography and Kinesiology. 2011; 21(4):631-7. [DOI:10.1016/j.jelekin.2011.04.006] [PMID] [DOI:10.1016/j.jelekin.2011.04.006]
27. Esculier JF, Roy JS, Bouyer LJ. Lower limb control and strength in runners with and without patellofemoral pain syndrome. Gait & Posture. 2015; 41(3):813-9. [DOI:10.1016/j.gaitpost.2015.02.020] [PMID] [DOI:10.1016/j.gaitpost.2015.02.020]
28. Willson JD, Kernozek TW, Arndt RL, Reznichek DA, Straker JS. Gluteal muscle activation during running in females with and without patellofemoral pain syndrome. Clinical Biomechanics. 2011; 26(7):735-40. [DOI:10.1016/j.clinbiomech.2011.02.012] [PMID] [DOI:10.1016/j.clinbiomech.2011.02.012]
29. Chuter VH, de Jonge XAJ. Proximal and distal contributions to lower extremity injury: A review of the literature. Gait & Posture. 2012; 36(1):7-15. [DOI:10.1016/j.gaitpost.2012.02.001] [PMID] [DOI:10.1016/j.gaitpost.2012.02.001]
30. Briani RV, de Oliveira Silva D, Pazzinatto MF, Ferreira AS, Ferrari D, de Azevedo FM. Delayed onset of electromyographic activity of the vastus medialis relative to the vastus lateralis may be related to physical activity levels in females with patellofemoral pain. Journal of Electromyography and Kinesiology. 2016; 26:137-42. [DOI:10.1016/j.jelekin.2015.10.012] [PMID] [DOI:10.1016/j.jelekin.2015.10.012]
31. Makhsous M, Lin F, Koh JL, Nuber G, Zhang LQ. In vivo and noninvasive load sharing among the vasti in patellar malalignment. Medicine and Science in Sports and Exercise. 2004; 36(10):1768-75. [DOI:10.1249/01.MSS.0000142302.54730.7F] [PMID] [DOI:10.1249/01.MSS.0000142302.54730.7F]
32. Sawatsky A, Bourne D, Horisberger M, Jinha A, Herzog W. Changes in patellofemoral joint contact pressures caused by vastus medialis muscle weakness. Clinical Biomechanics. 2012; 27(6):595-601. [DOI:10.1016/j.clinbiomech.2011.12.011] [PMID] [DOI:10.1016/j.clinbiomech.2011.12.011]
33. Sheehan FT, Borotikar BS, Behnam AJ, Alter KE. Alterations in in vivo knee joint kinematics following a femoral nerve branch block of the vastus medialis: Implications for patellofemoral pain syndrome. Clinical Biomechanics. 2012; 27(6):525-31. [DOI:10.1016/j.clinbiomech.2011.12.012] [PMID] [PMCID] [DOI:10.1016/j.clinbiomech.2011.12.012]
34. Hodges PW, van den Hoorn W, Wrigley TV, Hinman RS, Bowles KA, Cicuttini F, et al. Increased duration of co-contraction of medial knee muscles is associated with greater progression of knee osteoarthritis. Manual Therapy. 2016; 21:151-8. [DOI:10.1016/j.math.2015.07.004] [PMID] [DOI:10.1016/j.math.2015.07.004]
35. Rudolph KS, Schmitt LC, Lewek MD. Age-related changes in strength, joint laxity, and walking patterns: Are they related to knee osteoarthritis. Physical Therapy. 2007; 87(11):1422-32. [DOI:10.2522/ptj.20060137] [PMID] [PMCID] [DOI:10.2522/ptj.20060137]
36. Ettinger WH, Afable RF. Physical disability from knee osteoarthritis: The role of exercise as an intervention. Medicine & Science in Sports & Exercise. 1994; 26(12):1435-40. [DOI:10.1249/00005768-199412000-00004] [PMID] [DOI:10.1249/00005768-199412000-00004]
37. Lawrence RC, Helmick CG, Arnett FC, Deyo RA, Felson DT, Giannini EH, et al. Estimates of the prevalence of arthritis and selected musculoskeletal disorders in the United States. Arthritis & Rheumatism. 1998; 41(5):778-99. [DOI:10.1002/1529-0131(199805)41:53.0.CO;2-V] https://doi.org/10.1002/1529-0131(199805)41:5<778::AID-ART4>3.0.CO;2-V [DOI:10.1002/1529-0131(199805)41:53.0.CO;2-V]
38. Letafatkar A, Rajabi R, Tekamejani EE, Minoonejad H. Effects of perturbation training on knee flexion angle and quadriceps to hamstring cocontraction of female athletes with quadriceps dominance deficit: Pre–post intervention study. The Knee. 2015; 22(3):230-6. [DOI:10.1016/j.knee.2015.02.001] [PMID] [DOI:10.1016/j.knee.2015.02.001]
39. Lloyd DG, Buchanan TS. Strategies of muscular support of varus and valgus isometric loads at the human knee. Journal of Biomechanics. 2001; 34(10):1257-67. [DOI:10.1016/S0021-9290(01)00095-1] [DOI:10.1016/S0021-9290(01)00095-1]
40. Andriacchi T, Andersson G, Örtengren R, Mikosz R. A study of factors influencing muscle activity about the knee joint. Journal of Orthopaedic Research. 1983; 1(3):266-75. [DOI:10.1002/jor.1100010306] [PMID] [DOI:10.1002/jor.1100010306]
41. Zhang LQ, Xu D, Wang G, Hendrix RW. Muscle strength in knee varus and valgus. Medicine and Science in Sports and Exercise. 2001; 33(7):1194-9. [DOI:10.1097/00005768-200107000-00018] [PMID] [DOI:10.1097/00005768-200107000-00018]

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