Relationship between Conducting Wave and Muscle Thickness In Multi-channel Surface EMG

Abstract

The elucidation of muscle activity is important in clinical fields such as diagnosis of sarcopenia. Muscular activity is regulated by types and number of motor units (MU). The action potential generated by MUs are measured as electromyography (EMG). The multi-channel surface EMG (sEMG) is used to analyze the conduction of muscle potential. It is recorded as the interference electric potential generated by MUs. In our previous study, we proposed a method for searching all conducting waves appearing quantitatively in the multi-channel sEMG by calculating the similarity of the waveforms. It has possibility to estimate the mobilization of MUs by examining conduction waves. However, consideration of the results required anatomical and physiological knowledge. One of the quantitative evaluations of muscles is the measurement of muscle thickness using ultrasonic images. In this study, we investigated the relationship between conducting waves and muscle thickness measurement on 10 subjects. We examined the frequency of muscle training, muscle thickness, and the multi-channel sEMG during isometric contraction for each subject. It was found that the conduction velocity of waves is related to the biceps muscle thickness. In addition, the number of conducting waves is related to the ratio of biceps muscle thickness to subcutaneous fat thickness.