Characteristics of Muscle Activity in Distal and Proximal Upper Extremities in Different Phases for Taiwan Olympic Female Archery Players

INTRODUCTION The performance ofan elite archer can be affected by effective control of muscle in the upper extremities. Moreover, archery can be described as a comparatively static sport requiring strength and endurance of the upper body, in particular of the forearm and shoulder girdle [1]. Thus, EMG provides useful information to investigate the static skill sof archery. So far, a contraction and relaxation strategy with regard to forearm muscles during the release of the bowstring has been observed and studied through EMG for different skill levels of players [2,3]. These studies showed that archers released the bowstring by active contraction of the forearm extensors, whereas a clear relaxation characterized the forearm after release. Improper contraction may lead the incorrect movement and hasten fatigue of the muscle, as seen in beginner archers. However, most studies of the relaxation of release only focus on either the forearm or certain shoulder muscles (e.g., the right trapezius). There is no study that investigates how different contraction and release strategies might apply from the distal to proximal segments of the upper extremities, especially in world rank elite archers. Thus, the purpose of this study was to (1) investigate this strategy in the limb extremities from distal to proximal segments using Olympic Female Archery Players, (2) quantify relaxation strategy which was indicated by reduction in muscle activation before and after the release, and (3) determine the characteristic of reduction level of muscle activities in supplemental studies of anchoring and aiming. These studies can provide archers and coaches with the possible assessments of optimal skill patterns.