of the muscles involved, and cooperation among muscles may induce force fluctuations in
multiple directions. A novel setup for recording three-dimensional forces was developed to
assess the effects of muscle fatigue on submaximal contractions. Fifteen subjects performed
isometric dorsiflexions, elbow flexions, knee extensions, plantarflexions, and trunk
extensions (12s, 2.5–80% of maximal voluntary force) before and after a fatigue protocol …