2010 Volume 20 Pages 217-224
The present study investigated the muscle activity characteristics of scapular muscles, mainly the rhomboid muscle, during shoulder movement. The study population comprised 6 male college students with no history of shoulder injury. We recorded the EMG of some scapular muscles during shoulder abduction : the rhomboid major and minor muscles were tested using a wire electrode; the serratus anterior and the middle trapezius, by a surface electorode. It was found that with the increase in the shoulder angle and load, the muscle activity of each scapular muscle increased significantly. In particular, the muscle activity differed between rhomboid minor and major muscles, and it was believed that the muscle activity of the rhomboid minor and serratus anterior increased with load. Therefore, it was thought that the rhomboid minor and serratus anterior muscles show load dependence, and the possibility that the coordinated movement between the muscles plays a role in the maintenance of the scaplothoratic joint during shoulder abduction was suggested.
