INTERSEGMENTAL DYNAMICS ANALYSIS OF THE PENETRATING STRIKE AND SURFACE STRIKE IN CHINESE MARTIAL ARTS

Abstract

INTRODUCTION: In the process of Chinese martial arts upper limb striking, techniques vary. Sometimes requiring power that penetrates the target (penetrating strike), while other times just hitting the surface (surface strike). What happens in the limb that is different in these two strikes? What is the external and internal mechanism? Previous punching research focused on striking movement characteristics and results (Feld,1970; Cavanagh, 1975; Atha,1985). Such studies do not address the internal changes of joints and muscle torque within a striking motion itself. Thus they do not understand the process of coordination and control within such action. The purpose of this study was to analyze the coordination and control differences between a penetrating strike and a surface strike through intersegmental dynamics (developed by Zernicke & Co. 1986; 1989a; 1989b). METHODS: Subjects were 12 volunteers from the Chinese Martial Arts Department of the Chinese Culture University (height 178±5.68cm; BW 66±7.88 kg, age 22±4.03 years), who performed penetrating strikes and surface strikes. A 2D Peak Performance Motion Analysis System was used to analyze the motion. The target was a self-designed target structure. RESULTS: [Figure] Fig. 1. Elbow & shoulder joint muscle torque (Me, Ms) with penetrating & surface strike time curves. CONCLUSIONS: 1. The motion-dependent torque caused by UAA (upper-arm angular acceleration) just before impact is similar to the muscle torque of the elbow and shoulder both in the penetrating and surface strikes. The UAA at the elbow and shoulder were used to counterbalance the torque produced by FAA (forearm angular acceleration). 2. The main difference between the penetrating and surface strikes was in Me. In the penetrating strike, Me extends just before impact again. That means the subjects actively want to fix their elbow to hit the target. But in the surface strike, Me did not extend again.