Method to measure muscular fatigue in VDT tasks

This study was designed to evaluate localized muscular fatigue induced during VDT tasks, using an experimental paradigm where EMG signals were not recorded during the VDT task but during isometric contractions in which the load imposed on the shoulder muscle was kept constant. The change in MPF and the root mean square (RMS) values of EMG signals with time was explored. The correspondence between these measures and the psychological rating of localized muscular fatigue was also examined. On the basis of the results, the effectiveness of the experimental paradigm and of the measures used for evaluation of localized muscular fatigue was discussed. As a result, MPF measured during isometric contraction was found to be a sensitive measure of localized muscular fatigue.