鉛球投擲臂之肌電圖分析

Abstract

目的：探討不同重量鉛球（8、12、16磅）站立式投擲臂關節肌肉活動控制的機轉與模式。方法：以7位男性鉛球選手為研究對象，使用二台高速攝影機(125Hz)同步收集投擲動作影像資料，並與肌電系統(1,250Hz)，同步收集資料。結果：投擲16磅鉛球時的前臂屈肌標準化積分肌電顯著大於投擲8磅鉛球時；投擲12磅鉛球時，前臂伸肌標準化積分肌電與投擲距離成顯著正相關(r=0.855)；投擲16磅鉛球時，前鋸肌標準化積分肌電與投擲距離成顯著正相關(r=0.860)。結論：本研究揭示了鉛球投擲之關節肌肉作用控制的機轉，針對最後用力期發力之上臂肌群，教練選手應專注於鎖骨處胸大肌、胸骨處胸大肌、前、中三角肌及前臂屈、伸肌，執行鉛球投擲之投擲臂專項訓練，並且能注意拮抗肌的收縮，以有效地穩定投擲臂，充分發揮肌肉收縮的效率。

This study investigated the muscular activation patterns of the throwing arm of shot-put standing throw with different weights (8, 12 and 16 lbs.). Seven male shot putters served as subjects. Two high-speed cameras and the electromyography system were synchronized to collect data. The IEMG of forearm flexor during 16-lb. shot-putting was significantly greater than that during 8-lb. shot-putting. There was a significant positive correlation (r=0.855) between the IEMG of forearm extensor and the measured distance during 12-lb. shot-putting. Also found was a significant positive correlation (r=0.860) between the IEMG of serratus anterior and the measured distance during 16-lb. shot-putting. This study explored the muscular activation and control patterns of the throwing arm of shot-putting. It was concluded that coaches and shot-putters should focus on the specific training of the throwing arm in clavicular pectoralis major, sternal pectoralis major, anterior deltoid, middle deltoid, forearm extensor and forearm flexor, paying attention to the contraction of antagonist to effectively stablize the throwing arm during thrusting.