Citation

Missenard O, Mottet D, Perrey S. Exp. Brain Res. 2008; 185(1): 151-156.

Affiliation

EA 2991, University Montpellier 1, 700 av. du pic Saint Loup, 34090, Montpellier, France. olivier.missenard@univ-montp1.fr

Copyright

(Copyright © 2008, Holtzbrinck Springer Nature Publishing Group)

DOI

10.1007/s00221-007-1264-x

PMID

18205000

Abstract

The present experiment was designed to test the hypothesis that fatigue-induced impairment in movement accuracy is caused by a decrease in muscle cocontraction rather than a reduced ability to produce muscular force. Seven participants performed fast and accurate elbow extensions aimed at a target, before and after a fatigue protocol. The inertia of the manipulandum was decreased after the fatigue protocol so that the ratio of required to available force during movements was identical pre- and post-fatigue. After the fatigue protocol, movement endpoint accuracy decreased and movement endpoint variability increased. These alterations were associated with a decrease in cocontraction. We concluded that the impairment of movement accuracy during fatigue could not be explained by the lack of available force, but was likely to be due to a fatigue-induced decrease in muscular cocontraction. We then speculate that fatigue influences the relative weights of accuracy and energy economy in the optimisation of sensorimotor control.

Language: en