Effect of unilateral knee extensor fatigue on force and balance of the contralateral limb.

Purpose: Fatigue in one limb can decrease force production in the homologous muscle as well as other muscles of the non-fatigued limb affecting balance. The objective of the study was to examine the effect of unilateral knee extensor fatigue on the non-fatigued limb's standing balance, muscle force and activation.

Method: Sixteen healthy male subjects performed pre-fatigue balance trials, warm-up exercises, maximum voluntary isometric contractions, a knee extensors fatigue protocol, and post-fatigue balance trials.