The Possibility for Awareness of Others to Muscle Fatigue

- Examination by Isometric Contraction of Knee Extensor Muscle -

Abstract

The study aimed to assess whether it was possible for physiotherapists to be awareness to local muscle fatigue. In experiment I, we examined subjective fatigue reproducibility at different muscle contraction strengths. In experiment II, the effect of subjective fatigue on local muscle fatigue, assessed by electromyography (EMG) frequency and acceleration, was examined. The results suggested a relationship between the local EMG frequency component and physiological tremor assessed during severe fatigue onset, when the patella setting was sustained at 50% and 75% maximum voluntary contraction. In experiment III, which was the core of the present study, we possible for awareness of others to muscle fatigue was examined with different visual inputs. The results suggest that awareness of others fatigue through visual input, including facial expressions, and we need to pay particular attention to the changes around the eyes, eyebrows, and lips.