Effects of Limb-Specific Fatigue on Motor Learning during an Upper Extremity Proprioceptive Task

Background: The effects of limbspecific fatigue on motor skill acquisition and retention are not clear. Objective: To investigate the impact of limbspecific fatigue on the acquisition and retention of an upper extremity proprioceptive task. Methods: Twentytwo righthanded participants were randomly and equally assigned to either fatigued or nonfatigued protocols. Acquisition phase for the upper extremity task consisted of 5 blocks each with 12 trials. After 48 hours, all participants performed 1 block retention test (12 trials) with the left arm followed by 1 block transfer test (12 trials) with the right arm. Performance for each block was analyzed using a oneway analysis of variance (ANOVA). Performance differences between groups for the acquisition was analyzed using a 2 x 5 (group x block) ANOVA with repeated measures on the blocks. The performance on retentiontransfer was analyzed by separate ANOVAs. Statistical significance set at p .05. Results: The fatigued condition displayed significantly more E than the nonfatigue group (p .05). During retention and transfer, the fatigue group again displayed higher E compared to the nonfatigued group (p .05). Conclusion: The results of this study support that limbspecific fatigue may produce performance deficits during acquisition and interfere with motor skill retention.