Work and peak torque during eccentric exercise do not predict changes in markers of muscle damage. Issue 7 (14th September 2007)

• Record Type: Journal Article
• Authors: Chapman, D W; Newton, M J; Zainuddin, Z; Sacco, P; Nosaka, K
• Is Part Of: British journal of sports medicine. Volume 42:Issue 7(2008)
• Page Start: 585
• Page End: 591
• Publication Date: 2007-09-14
• Subjects: Sports medicine -- Periodicals; 617.1027
• DOI: 10.1136/bjsm.2007.037929
• Languages: English
• ISSNs: 0306-3674

Abstract

Abstract : Objectives: Large inter-subject variability in responses to eccentric exercise has been reported. This study investigated the hypothesis that the variability of changes in indirect markers of exercise-induced muscle damage (EIMD) would be explained by work performed and/or torque generated during eccentric exercise. Methods: Subjects (n = 53) performed 60 maximal eccentric actions of the elbow flexors on an isokinetic dynamometer that forcibly extended the elbow joint from 60° to 180° at a constant velocity (90° s −1 ). Markers of EIMD included maximal voluntary isometric contraction torque at 90° elbow flexion (MVC), range of motion, plasma creatine kinase activity and muscle soreness. Measurements were taken 2 days before, immediately after and 1–4 days post-exercise. Pearson's correlation coefficient was used to examine relationships between exercise parameters (total work, change in total work, torque produced during exercise, change in peak torque) and markers of EIMD. Results: Large inter-subject variability was evident for both work and torque during exercise, and changes in all markers of EIMD. Contrary to the hypothesis, total work (normalised for individual pre-exercise MVC) did not correlate significantly with any markers of EIMD, with the exception of MVC (r = 0.3). Total work performed and changes in total work showed higher correlations with some markers, but no r-values exceeded 0.4. Normalised exercise torque and the changes in peak torque during exercise were not correlated with changes in MVC, or other markers. Conclusion: These results suggest the large inter-subject variability in responses to eccentric exercise is not associated with work performed or torque generated during eccentric exercise.