Author: Wong, Kwai-lan
Title: A study of antagonist/agonist isokinetic work ratios of shoulder muscles on experienced sport climbers
Degree: M.Sc.
Year: 2007
Subject: Hong Kong Polytechnic University -- Dissertations.
Shoulder -- Muscles.
Sports injuries.
Rock climbing.
Isokinetic exercise.
Department: Department of Rehabilitation Sciences
Pages: xiii, 84 leaves : ill. ; 31 cm.
Language: English
Abstract: Background: Sport climbers have high incidence of shoulder injuries, however, biomechanical studies of the shoulder of the sport climbers are lacking. Knowing the isokinetic work profile of the shoulder agonists and antagonists is important for these athletes as it could provide quantitative information on the relationships of the respective muscle groups and identify particular muscle imbalance. Objective: In this study, the isokinetic conventional and functional work ratios of two shoulder agonist/antagonist muscle pairs of sport-climbers were examined and compared with the non-climbers. The two shoulder agonist/antagonist muscle pairs tested were 1) flexors / extensors and 2) external/ internal rotators. Methods and Measure: Thirty-one elite sport climbers and 27 non-climbers with mean age of 28 to 33 years were tested. Isokinetic works of shoulder, including concentric flexion and extension (con F, con E), eccentric flexion and extension (ecc F, ecc E), concentric external and internal rotations (con ER, con IR) and eccentric external and internal rotations (ecc ER, ecc IR) were measured at a speed of 60o/s for all subjects. Conventional work ratios of con F/E, con ER/IR, ecc F/E and ecc ER/ IR and functional work ratios of ecc F/ con E, ecc ER/ con IR, ecc E/ con F and ecc IR/ con ER were then worked out. Result: All the work ratios found were significantly different between the climbers and the non-climbers (p< 0.005). All the mean conventional work ratios in the climbers (i.e. con F/E = 0.74, ecc F/E = 0.74, con ER/IR = 0.79 and ecc ER/IR = 0.88) were lower than 1 and these were smaller than those of the non-climbers (con F/E = 1.13, ecc F/E = 1.05, con ER/IR = 1.03 and ecc ER/IR= 1.13). Regarding the mean functional work ratios, the ecc F/con E and ecc ER/con IR in the climbers (0.90 and 1.05, respectively) were approaching 1:1 but these were lower than the non-climbers (1.46 and 1.30 respectively). The work ratios of ecc E/ con F and ecc IR/con ER, they were 1.73 and 1.58 respectively in the climbers which were higher than the non-climbers (1.28 and 1.17, respectively). Conclusion: From a functional point of view, the differences in work ratios in the two groups indicated differences in work profiles of the shoulders which could be a result of training-induced changes in the sport climbers. With reference to the work ratios in the sport climbers, training programs for the shoulders that have a balance on achieving functional needs and preventing pathological muscle imbalance are recommended for this athletic population.
Rights: All rights reserved
Access: restricted access

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