Analysis of connecting joint anglle and moment in arm landing action in Sports Aerobics

A relation between the movement range of arms and arising moment has been studied to find out efficient movement range to minimize impact concerning arm landing in sports aerobics. Four male athletes who won top three in national-level sports aerobics competition were chosen for the experiment. They were allowed to jump in between two force platform so that the right hand and the right leg could land onto the front and rear force platform, respectively. The sampling frequency was 200 Hz. The main conclusions based on the analysis of the angle and joint moment parameters of wrist, elbow, and shoulder are as follows: 1. The wrist moment was small when its angle was small, indicating that the dorsi-flexion of the wrist joint offered a positive influence to reduce wrist moment. 2. The elbow angle increased as wrist angle decreased and vice versa. This means that the movement range of the wrist joint affects that of the elbow joint. The darsi-flexion of the wrist is the position to absorb the impact of the elbow effectively rather than to absorb the impact of the wrist itself. The impact is absorbed by the flexion of wrist joint rather than the wrist. 3. The degree of moment transfer of the shoulder joint, having absorbed the impact from the elbow and elbow joint, became dependent on the efficiency of the fore-joints impact absorption.