Archery Skill Indexes: Estimation of Archers' Performance Level by Using Forearm Surface EMG Data

Abstract

Surface EMG signals of m. flexor digitorum superficialis (MFDS) and m. extensor digitorum (MED) were recorded of 23 subjects during archery shooting. Two-second periods (clicker falls at 1th sec) of 12 shots' EMG data were recorded, rectified and averaged (moving average filter) for each subjects. 7 and 6 of the subjects were elite and beginner archers respectively, while rest is non-archers. Intra-archer mean value (IAMV) and standard deviations (IASD) of cross-correlations (CC) were calculated for each archer. Kruskal-Wallis Statistic was used for subject's IAMVs or IASDs vs. skill groups. Variation among group medians of IAMVs was statistically significant (p<0.05) for both MED and MFDS. But variation among group medians of IASDs was statistically significant (p<0.05) for only MED. The results show that when archery experience increases archers contract their MED or MFDS more similarly since CCs of EMG waveforms increase. IAMVs and IASDs of CCs may be a good candidate for a) assessing shooting techniques b) evaluation of archers' progress, and c) selection of talented archers.