PT  - JOURNAL ARTICLE
AU  - Chapman, D W
AU  - Newton, M J
AU  - Zainuddin, Z
AU  - Sacco, P
AU  - Nosaka, K
TI  - Work and peak torque during eccentric exercise do not predict changes in markers of muscle damage
AID  - 10.1136/bjsm.2007.037929
DP  - 2008 Jul 01
TA  - British Journal of Sports Medicine
PG  - 585--591
VI  - 42
IP  - 7
4099  - http://bjsm.bmj.com/content/42/7/585.short
4100  - http://bjsm.bmj.com/content/42/7/585.full
SO  - Br J Sports Med2008 Jul 01; 42
AB  - 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.