Comparison of the parameters for muscle fatigue evaluation using surface electromyogram in repetitive exercise

This study is to compare the parameters for the quantitative evaluation of muscle fatigue using surface electromyograms (sEMG) in repetitive exercise. Thirty-seven medical staff members performed chest compression for 5 min on a manikin on a bed. sEMG was acquired from 3 muscles while compressing the chest according to the cardiopulmonary resuscitation (CPR) guidelines. sEMG electrodes were attached on the biceps brachii and triceps brachii which are fatigued and on the rhomboideus which is considered to be a non-fatigued muscle. Root mean square (RMS), median frequency (MDF) and one spectral index (FI_nsm5) were calculated to investigate the relationship with the time process, which is correlated with muscle fatigue. For the fatigued muscles, all the three parameters showed significant changes over time, whereas in non-fatigued muscle, none of the three parameters showed any significant change over time. All three parameters were shown to be suitable to assess the muscle fatigue in repetitive exercise. FI_nsm5 was more sensitive than the other two parameters, which may imply that FI_nsm5 is the most sensitive parameter for muscle fatigue among these three parameters.