The effects of gender and fatigue on dynamic postural control.

CONTEXT Deficits in static postural control related to fatigue have been investigated previously, but there is little evidence to link fatigue to performance measures of dynamic postural control. OBJECTIVE To investigate the effects of fatigue and gender on performance measures of the Star Excursion Balance Test (SEBT). DESIGN Mixed-model design. SETTING Research laboratory. PARTICIPANTS 16 healthy young adults. INTERVENTION Subjects performed the SEBT before and after 4 different fatiguing conditions. MAIN OUTCOME MEASURES The normalized reach distances and sagittal-plane kinematics of the knee and hip were recorded. RESULTS Fatigue produced deficits in normalized reach distances and decreased knee flexion in all 3 reaching directions. Overall, women were able to reach farther than men while simultaneously demonstrating a greater amount of knee flexion. CONCLUSIONS Gender differences were observed during performance of the SEBT, with women demonstrating greater reach distances and knee flexion, and fatigue amplified these differences.