Quantification of Muscle Fatigue Using Surface Electromyography for Isometric Handgrip Task

We proposed a method to quantitatively estimate the degree of muscle fatigue by constructing a fatigue index, which represents the relationship between the force loss and handgrip work. This fatigue model allows the estimation of force loss non-intrusively using SEMG signal. Eight male subjects volunteered in this study to perform a series of isometric handgrip tasks at three different contraction levels. Handgrip work was estimated from SEMG signal, which was then used as the independent parameter for the fatigue index to estimate the force loss. The evaluation was performed by comparing the force loss that was estimated using the proposed fatigue index and the one measured from dynamometer. The average error of the estimated muscle fatigue using the proposed method was less than 10% MVC.