RESEARCH IN UPPER EXTREMITY CHAIN'S AIMING TECHNIQUE OF ELITE ARCHER

To review previous study of archery, most-researchers focused their study on stability of archer. Dillman (1982) had even studied the stability of the centre of gravity. The results were that between elite archer and general archer there were no statistically significant differences in the amplitude of movement of the CG, and found the good results response were not small, but the middle level. Martin (1985) researched the vibration of the centre of gravity and the bow further. He also found that the amplitude vibration of the CG and the bow all couldn't distinguish the elite archer and the general archer. As we know, the trajectory of the arrow was controlled by the upper extremity chain, so it was necessary to investigate how the upper extremity influences the results. HF-I1 type Selespot System (made in QinHua University China) was applied to measure the 3D displacement of the selected point of upper extremity during the period of aiming. Nineteen athletes of National Archery Team (10 female, 9 male) participated in the measurement. According to the condition of competition, each person shot continuously 36 arrows. The distance was 50 meters. All good and bad results were processed statistically respectively. It was found that the movement of the interested point of upper extremity in horizontal plane statistically significant difference(p< 0.01) between good results and bad results during one second before release, but there was no statistically significant difference in the Z direction. The good results of female and male arrow group both showed that the arm of supporting bow and the arm of pulling bow had relatively larger amplitude of the movement, faster speed and acted on the bow smoothly, but the shoulder had small amplitude, in other words, shoulder had high stability. We present the basic principle of aiming technique of upper extremity. It is required that the archer at first aim somewhere near the target centre regularly, and then, faster, smoothly, precisely approach the centre and release the arrow when pulling the bow is proceeding