مرکز منطقه ای اطلاع رساني علوم و فناوري - Differences in Activation Patterns of Shoulder Girdle Muscles in Recurve Archers

Abstract :

The purpose of this study was to observe the differences in activation patterns in shoulder girdle muscles of drawing and bow arm during archery shooting. 96 shots of eight associate archers for Turkish junior national team were analyzed in the current study. Each archer has shot 12 arrow to the target, EMG activities of M. Deltoid Middle (DM) and Posterior, M. Trapezius Middle (TM) and Lower (TL) were quantified in both drawing and bow arm. The measurement sites were prepared according to SENIAM’s recommendations. Pass band of EMG amplifier, sampling rate, maximum intra-electrode impedance and common mode rejection ratio (CMMR) were 8-500 Hz, 1000 Hz, 6 Kohms and 95 dB, respectively. Three-second periods of twelve shots, which contain full draw, aiming and release phases respectively, EMG data were full-wave rectified and filtered (moving average filter with 60 ms time-window) for each archer. ANOVA test and Tukey post hoc were used to assess the differences in activation patterns in each muscle among periods. Drawing arm normalized DM iEMG activity was significantly low in release period (DM MVC %; Full draw; 17.892±7.505 aiming period; 20.941±10.556; releasing period; 8.312±6.3) (p 0.05). Drawing arm DP muscle activation was significantly higher full draw (16.593±4.585) and aiming period (18.801±5.546) then releasing period (6.787±6.068). TM and TL iEMG activities in the drawing arm have been statistically higher in aiming period (p 0.05). Bow arm DM and DP muscle activities were statistically lower (DM: 15.985±8.729; DP:10.03±5.865) in releasing period. Similar statistical differences in bow arm TM and TL muscles can be seen in releasing period.