Different Activity Level And Functional State Of Semg Signal Frequency Characteristic Changes

The goal of this study was to evaluate the changes of the agonist-antagonist muscles' surface electrical activities which induced by different active levels and function states on the time and frequency domain. The agonist-antagonist muscles are biceps brachii(BB) and triceps brachii(TB). The indices' change rules and validities under static and dynamic exercise were studied using four indices including integrated electrorayography(iEMG), root mean square(RMS), median power frequency(MPF) and mean frequency(MF), while the relevance of the two agonist-antagonist muscles was analyzed.The results indicated that the time domain indices were increasing as the function of force level. The frequency domain indices showed an increase as the function of force level for contractions to 50% maximum voluntary contraction, followed by a decrease for contraction above this level. The time and frequency domain indices showed different rules in static and dynamic fatigue exercises. The iEMG and RMS showed an increase while the MPF and MF showed a decrease as the function of sustained time. The BB muscle and TB muscle' s surface electrical activities hadn' t the same regularities during fatigue and there were different significance relativities of different indices between the two muscles.