SHOULDER JOINT VELOCITY DURING FASTBALL PITCHING IN BASEBALL

Abstract

The purpose of this study was to assess the rotation and translation velocity of the shoulder complex during fastball pitching in baseball. 8 pitchers from the Dutch AAA team performed each 3 fastball pitches. Their motion was recorded by an opto-electronic device. Kinematic computation was performed using the quaternion algebra. The results showed that the endo-rotation, depression and backward rotation velocity of the humerus at ball release are initiated by a translation of the scapular girdle in the forward and upward direction before ball release.