Temporal Changes in Muscle Activities of the Soleus and the Medial Head of the Gastrocnemius during the Standing Heel Raise Movement

Abstract

[Purpose] This study examined the muscle activities of the plantar flexor muscles during the standing heel raise. [Participants and Methods] The subjects were 18 healthy adults. Electromyograms (EMG) of the right soleus muscle (SOL) and the right medial head of gastrocnemius muscle (MG) were measured for 1,000 ms during heel raises from the standing posture initiated by a metronome. EMG integral values were collected at intervals of 200 ms from the metronome beat, and compared with the relative EMG integral values of the muscle activity in the standing posture. [Results] SOL showed an increase in muscle activity from the initial to the middle phase of the movement, and a decrease in muscle activity in the terminal phase of the movement. On the other hand, MG showed an increase in muscle activity over time. [Conclusion] Muscle activity of the SOL decreased toward the end of the movement during the standing heel raise movement.