神經肌肉電刺激對鉛球站立式投擲之立即性運動學表現分析

Immediate effect of neuromuscular electrical stimulation on kinematics of shot put stand throw

緒論：鉛球投擲技術分為旋轉與滑步式，須具備一定的速度、爆發力、協調性等身體素質。研究旨在分析神經肌肉電刺激介入訓練對鉛球投擲成績的影響，探討鉛球投擲技術與各動作階段之運動學差異。方法：以未接受過電刺激的15名體育學院男性大學生為研究對象，使用2臺高速攝影機進行同步拍攝電療前與電療後鉛球投擲動作，經由Kwon3D動作分析系統進行三維運動學影像分析。以Wilcoxon signed-rank test考驗電療前與電療後鉛球在各動作階段參數之差異。結果：電療後之投擲距離較電療前遠（p < .01）；電療後之出手速度較電療前快（p < .01）。電療後重心最低之踝關節角度較電療前大（p< .05）；電療後左腳離地之踝關節角度較電療前大（p < .01）；電療後右腳離地之踝關節角度較電療前大（p < .05）。電療後投擲階段之肩-髖分離角較電療前小（p < .05）；電療後轉身階段之肩-髖分離角較電療前大（p < .05）；電療後轉身階段之左腳踝關節角度較電療前小（p < .05）。結論：神經肌肉電刺激對鉛球的投擲產生影響，適宜的電刺激可以增進肌肉活化，使肌肉的收縮力量增大，並對運動能力與鉛球的投擲成績有提高作用。

Introduction: Shot put throwing techniques are divided into spinning and sliding, and must have certain physical qualities such as speed, explosive power, and coordination. The purpose of this study was to analyze the effect of neuromuscular electrical stimulation intervention training on shot put throwing performance and to explore the shot put throwing technique and kinematic differences at each movement stage. Methods: Fifteen male college students who had not received electrical stimulation previously were the research participants. Two high-speed cameras were used to obtain synchronous images of shot put throwing actions of the participants before and after electrotherapy. Three-dimensional kinematic image analysis was performed using the Kwon 3D motion analysis system. The Wilcoxon signed-rank test was used to test differences in shot put parameters at each action stage before and after electrotherapy. Results: Throwing distance was longer (p < .01) and throwing speed was faster (p < .01) after electrotherapy than before electrotherapy. The ankle joint angle with the lowest center of gravity (p < .05), ankle joint angle of the left foot off the ground (p < .01), and ankle joint angle of the right foot was off the ground (p < .05) were greater after electrotherapy than before electrotherapy. The shoulder–hip separation angle in the throwing stage was smaller (p < .05), shoulder–hip separation angle in the turning stage was larger (p < .05), and left ankle joint angle in the turning stage was smaller (p < .05) after electrotherapy than before electrotherapy. Conclusion: Neuromuscular electrical stimulation has an impact on shot put throwing. Appropriate electrical stimulation can enhance muscle activation, increase muscle contraction force, and improve athletic ability and shot put throwing performance.