PHYSIOLOGICALLY REASONABLE ‘TORQUE REVERSAL’ CAUSED IN COMPUTERSIMULATED PLANAR BALL THROWING DOES NOT INCREASE BALL SPEED AT RELEASE

Abstract

INTRODUCTION: Herring and Chapman (1992) reported that some torque reversals caused by the agonist deactivation and the antagonist activation at the proximal joints of a planar three link segment model for ball throwing with the upper extremity increased ball speed at ball release. The paper has often been referred as the study showing possible positive roles of antagonisms for planar motions (Sorensen et al. 1996; Do”rge et al., 1999) in spite of its unrealistically rapid torque reversal for human movements. The purpose of this study was to investigate influences of the speeds of the deactivation and activation on the ball speed in computer-simulated ball throwing using a model similar to that used by Herring and Chapman (1992).