Altered force-generating capacity is well-perceived regardless of the pain presence

An inability to perceive changes in action capabilities may result in increased risk of injury and/or reduced performance. We investigated whether the perception of ability to perform a maximal single-leg hop was updated when the actual ability to perform the task was reduced due to experimentally altered force-generating capacity and associated pain. Twenty-five healthy volunteers performed a series of maximal isometric voluntary knee extensions (MVC), performance estimates and actual performances of a maximal single-leg hop. The motor tasks were completed for each leg, before (t), and immediately (t), 48 hr (t) and 1 month (t) after, a neuromuscular electrical stimulation (NMES) protocol was used to decrease the force generating capacity of the quadriceps muscle of 1 leg. MVC torque decreased by ~30% after the NMES protocol for the stimulated leg at t and t (p < .001). This reduction was associated with a significant decrease in estimation of performance and actual performance of the maximal single-leg hop at t and t for the test leg (p < .001). The reduction in performance ability was associated with low-level pain immediately after NMES, and moderate pain and an increase in the belief that everyday motor tasks would be harmful 48 hours after NMES. Participants accurately estimated their performance capabilities during each testing period. This study provides a critical step toward understanding the potential for decreased force-generating capacity and muscle pain to modify the relationship between motor performance and perceived abilities