揮擊加重棒球對揮棒速度、球撞擊後速度、撞擊能量及肌肉活性之影響

Effects of Hitting Weighted Baseball on Swing Velocity, Ball Batted Velocity, Impact Energy, and Muscle Activity

鍾陳偉(Chen-Wei Chung)

《華人運動生物力學期刊》 2期 (2010/04) Pp. 1-8

摘要

前言：本研究目的在於探討棒球選手在揮擊加重棒球過程中，對揮棒速度、球撞擊後速度、撞擊能量及肌肉活性之影響，用以驗證揮擊加重球是否適合做為新式打擊訓練方法。方法：受試對象為12名世新大學棒球隊選手，以比賽用木棒隨機揮擊正常棒球和2倍重的加重棒球，分別利用十台Eagle紅外線攝影機（250Hz）之Motion Analysis System分析揮棒速度和球撞擊後速度、Biopac三軸加速規分析球與球棒的碰撞時前導手腕關節之撞擊能量、Biovision肌電儀分析前導手屈腕和伸腕肌群之肌肉活性。結果：（1）揮擊正常棒球和加重棒球時之揮棒速度未達顯著差異（p ＞. 05），（2）加重棒球的撞擊後速度顯著慢於正常棒球（p ＜. 05），（3）揮擊加重棒球時的腕關節之合加速度最大值顯著大於揮擊正常棒球時（p ＜ .05），（4）揮擊加重棒球時前導手屈腕和伸腕肌群之肌肉活性均顯著大於揮擊正常棒球時（p ＜ .05）。結論與建議：結果顯示揮擊加重棒球不會影響擊球前的揮棒表現，但會因球體重量較重，減慢球擊出的速度，並對前臂肌群有較大的肌肉收縮刺激，且對腕關節有較大的負荷；本研究認為揮擊加重球的打擊訓練，具有模擬揮擊快球速時的高撞擊能量之效果，並能有效地刺激旋轉腕關節揮棒所需的前臂肌群。

關鍵字

揮棒 ； 棒球 ； 加重球

並列摘要

Background: The purpose of this study was to investigate effects of hitting weighted baseballs on swing velocity, batted-ball velocity, impact energy, and muscle activity. It was to examine if weighted baseballs could be used as a new hitting training method. Methods: 12 baseball players were recruited from Shih-Hsin University. They randomly hit normal baseballs and weighted baseballs (two times heavier than a normal baseball) by using the same bat. Motion Analysis System, three-dimensional accelerometer, and surface EMG were used in this study. Results: The swing velocity showed no significant difference between normal and weighted baseballs (p ＞ .05). The batted-ball velocity of weighted baseballs was significantly slower than that of normal baseballs (p ＜ .05). The value of maximum resultant acceleration at wrist joint was significantly higher during hitting weighted baseballs than hitting normal baseballs (p ＜ .05). Muscle activities of flexor and extensor were significantly higher during hitting weighted baseballs than hitting normal baseballs (p ＜ .05). Discussion: Hitting weighted baseballs would not affect swing performance before collision, but it would lead to slower batted-ball velocity and cause stronger muscle contraction of forearm muscles. However, the impact load was greater at wrist joint due to the larger weight of the ball. Conclusions: The study suggested that hitting weighted baseballs could be a new way of batting practice. Not only was the impact energy of hitting weighted baseballs similar to hitting a fast pitch, but the forearm muscles that bring the wrist joint to rotate during batting were also fully stimulated.

並列關鍵字

swing ； baseball ； weighted baseball