THE STUDY OF SHOULDER INTERNAL AND EXTERNAL ROTATION STRENGTH IN COLLEGE BASEBALL PLAYERS

Abstract

The purpose of this study was to investigate the different of dominant arm shoulder rotation torque between the baseball pitchers, infielders, and ouffielders. Participants were 27 first-level collegiate baseball players, including 9 pitchers, 10 infielders, 8 outfielders. A Biodex lsokinetic Dynamometer was used for estimation of shoulder muscle strength. This system's test velocity was set at 60 "Is and the range of motion of dominant arm shoulder in flexion, abduction, 90' of abduction with external rotation, and 90" abduction with internal rotation. The results indicated that there was no significant different in internal rotation peak torque and ERllR ratio between pitchers, infielders, and outfielders. There was significantly different in external rotation peak torque. The infielders and ouffielders possess greater external rotation peak torque than pitchers.