Assessing muscle fatigue by measuring the EMG of biceps brachii

The purpose of this study is to measure the surface electromyography (sEMG) to assess the muscle fatigue endurance when doing the forearm contraction exercise. There were six subjects (24.4 ± 1.35 years, height 176.8 ± 7.41cm and weight 72.2 ± 2.48 kg) who completed endurance repetitions forearm exercise of lifting 12 lb dumbbell and the sEMG signal of each subject´s biceps brachii were recorded. Signal of maximal voluntary contraction (MVC) were measured before and after exercise. Median (MedF) and mean (MF) spectral frequency of MVC were calculated for each percentage of repetition. The calculated results indicated that the later exercise (endurance concentric contraction) indicated the muscle fatigue between 90% and 100% (muscle fatigue phase) of time percentage and the linear regression of spectral frequency (MedF, MF) indicated that the line equations can be used to assess the tendencies of muscle fatigue.