DOES CALF-MUSCLE FATIGUE AFFECT STANDING BALANCE

The purpose of this study was to find out whether fatiguing calf-muscl e exercise affects postural sway during standing. Thirteen healthy sub jects with a mean age of 25 years participated. Body sway in one leg s tance was measured on a force plate before and after fatiguing exercis es of the calf muscles of the subject's right leg. Repeated measuremen ts for up to 10 min after exercises showed no increase of body sway. T he results indicate that postural control in quiet standing can be mai ntained by compensatory mechanisms activated during muscle fatigue. A significant decrease of body sway over time on the nonfatigued leg ind icated a learning effect. A similar decrease was not observed on the f atigued leg, indicating interference of compensatory mechanisms on lea rning.