Azadeh Kian, Farhad Tabatabi Ghomshe and Zohreh Norang
The main purpose of this study was to compare the ability of archers in two different levels of expertise in controlling the bow during aiming phase. To achieve best control on the bow, the critical point for archers is to use bones, not muscles. Magnitude of postural angles and also total moment in the bow wrist joint can be good indicators of wrist muscles activity. Two female archers in elite and beginner levels of skill had participated in this research. 3-D coordinate data of upper body marker set were collected at 200 Hz using motion analysis system. Hyperextension and ulnar deviation angles during aiming phase were obtained from kinematic analysis. Moreover, moments were calculated by implementing static equilibrium equations to the biomechanical model of archer's bow hand. Results revealed that muscles responsible for hyperextension and ulnar deviation are significantly more activated in the beginner archer. Having muscles highly contracted, makes the beginner archer tired much sooner. This will cause the archer's ability descend during competition. Therefore control ability of bow wrist can be an indicator of archer's skill level and applied as an important parameter in talent identification, training, skill level estimation and assessment of performance improvement in archers.