Abstract
The ability to rapidly adjust actions and adapt to perturbations is crucial in supporting rehabilitation and athletic performance. Online control relies on the integration of numerous sources of sensory information, including proprioception and vision. Although previous studies have found that exercise induced muscle damage (EIMD) reduces the acuity of proprioceptive sensory feedback, the effects of EIMD on online movement control remain unknown. To address this knowledge gap, participants performed 4 sessions of rapid, goal-directed, upper limb reaching movements prior to (baseline), after (immediately-post) and 24-48 hours after (delayed-post) damaging eccentric exercise. In 30% of the reaching trials, participants had to adapt their trajectory to either a shift in target location (visual perturbation) or a force applied to the arm (force perturbation). In the exercise protocol, participants completed eccentric bicep curls using 30% of their maximum voluntary contraction until volitional failure. In response to the exercise session, participants' force output was reduced, indicating that EIMD was successfully induced. Furthermore, in the immediate and delayed post-exercise reaching trials, participants were less accurate and less precise in both visual and force perturbation trials. These findings suggest that EIMD may decrease our ability to react to changes in the environment. Future research may use this information to determine optimal rest and recovery protocols to avoid decrements in motor coordination performance due to EIMD.
