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Original article
Impact of exercise selection on hamstring muscle activation Matthew N Bourne,1,2,3 Morgan D Williams,4 David A Opar,5 Aiman Al Najjar,6 Graham K Kerr,1,2 Anthony J Shield1,2 1
Faculty of Health, School of Exercise and Nutrition Science, Queensland University of Technology, Brisbane, Australia 2 Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia 3 Queensland Academy of Sport, Centre of Excellence for Applied Sport Science Research, Brisbane, Australia 4 Faculty of Life Sciences and Education, School of Health, Sport and Professional Practice, University of South Wales, Wales, UK 5 School of Exercise Sciences, Australian Catholic University, Melbourne, Australia 6 Centre for Advanced Imaging, University of Queensland, Brisbane, Australia Correspondence to Dr Anthony Shield, School of Exercise and Nutrition Sciences and the Institute of Health and Biomedical Innovation, Queensland University of Technology, Victoria Park Road, Kelvin Grove, Brisbane, QLD 4059, Australia; aj.shield@qut.edu.au Accepted 16 April 2016 Published Online First 13 May 2016
ABSTRACT Objective To determine which strength training exercises selectively activate the biceps femoris long head (BFLongHead) muscle. Methods We recruited 24 recreationally active men for this two-part observational study. Part 1: We explored the amplitudes and the ratios of lateral (BF) to medial hamstring (MH) normalised electromyography (nEMG) during the concentric and eccentric phases of 10 common strength training exercises. Part 2: We used functional MRI (fMRI) to determine the spatial patterns of hamstring activation during two exercises which (1) most selectively and (2) least selectively activated the BF in part 1. Results Eccentrically, the largest BF/MH nEMG ratio occurred in the 45° hip-extension exercise; the lowest was in the Nordic hamstring (Nordic) and bent-knee bridge exercises. Concentrically, the highest BF/MH nEMG ratio occurred during the lunge and 45° hip extension; the lowest was during the leg curl and bentknee bridge. fMRI revealed a greater BF(LongHead) to semitendinosus activation ratio in the 45° hip extension than the Nordic ( p
Original article
Impact of exercise selection on hamstring muscle activation Matthew N Bourne,1,2,3 Morgan D Williams,4 David A Opar,5 Aiman Al Najjar,6 Graham K Kerr,1,2 Anthony J Shield1,2 1
Faculty of Health, School of Exercise and Nutrition Science, Queensland University of Technology, Brisbane, Australia 2 Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia 3 Queensland Academy of Sport, Centre of Excellence for Applied Sport Science Research, Brisbane, Australia 4 Faculty of Life Sciences and Education, School of Health, Sport and Professional Practice, University of South Wales, Wales, UK 5 School of Exercise Sciences, Australian Catholic University, Melbourne, Australia 6 Centre for Advanced Imaging, University of Queensland, Brisbane, Australia Correspondence to Dr Anthony Shield, School of Exercise and Nutrition Sciences and the Institute of Health and Biomedical Innovation, Queensland University of Technology, Victoria Park Road, Kelvin Grove, Brisbane, QLD 4059, Australia; aj.shield@qut.edu.au Accepted 16 April 2016 Published Online First 13 May 2016
ABSTRACT Objective To determine which strength training exercises selectively activate the biceps femoris long head (BFLongHead) muscle. Methods We recruited 24 recreationally active men for this two-part observational study. Part 1: We explored the amplitudes and the ratios of lateral (BF) to medial hamstring (MH) normalised electromyography (nEMG) during the concentric and eccentric phases of 10 common strength training exercises. Part 2: We used functional MRI (fMRI) to determine the spatial patterns of hamstring activation during two exercises which (1) most selectively and (2) least selectively activated the BF in part 1. Results Eccentrically, the largest BF/MH nEMG ratio occurred in the 45° hip-extension exercise; the lowest was in the Nordic hamstring (Nordic) and bent-knee bridge exercises. Concentrically, the highest BF/MH nEMG ratio occurred during the lunge and 45° hip extension; the lowest was during the leg curl and bentknee bridge. fMRI revealed a greater BF(LongHead) to semitendinosus activation ratio in the 45° hip extension than the Nordic ( p
