目的：本研究探討透過藥球訓練的介入，對青少年棒球選手投球時肩髖分離程度以及投球的球速的差異。方法：以18位青少年棒球選手作為研究參與者，分為實驗組與控制組，實驗組進行為期8週、每週2次的藥球介入訓練，在訓練前後對投擲動作進行分析，利用陀螺儀及測速槍分析肩平面角速度變化、肩平面角位移、髖平面角速度變化、髖平面角位移、肩髖角度差、肩部旋轉角速度峰值、肩部旋轉峰值時機、髖部旋轉角速度峰值、髖部旋轉峰值時機、投球動作時間及球速。以混合設計二因子變異數分析比較實驗組與控制組在藥球訓練介入前後的差異。結果：本研究結果發現，實驗組經過8週藥球介入訓練後，球速顯著大於控制組 (F=18.2, p=.009*)；實驗組與控制組在肩平面角位移皆為後測顯著大於前測 (F=405, p<.001*; F=53.2, p<.001*)，且實驗組於後測顯著大於控制組 (F=26.9, p<.001*)；實驗組經由介入訓練後，髖平面角位移顯著變小 (F=12.9, p=.002*)，而控制組則是顯著變大 (F=24.28, p<.001*)，但兩者間並無差異；肩髖角度差為實驗組後測顯著大於前測 (F=432, p<.001*)，且藉由訓練後顯著大於控制組後測 (F=82.1, p<.001*)；投球動作時間在兩組經由介入訓練後，顯示無顯著差異；肩部旋轉角速度峰值為實驗組後測顯著大於前測 (F=33.034, p<.001*)，且訓練後顯著大於控制組後測 (F=17.062, p=.001*)；肩部旋轉時機為實驗組後測顯著大於前測 (F=34.067, p<.001*)，且訓練後顯著大於控制組後測 (F=18.512, p<.001*)；髖部旋轉角速度峰值經過介入訓練後並無顯著差異；髖部旋轉峰值時機為實驗組後測顯著小於前測 (F=323.039, p<.001*)，且訓練後顯著小於控制組後測 (F=281.339, p<.001*)。結論：本研究結果顯示藥球介入訓練對於青少年棒球選手投球時提高肩髖分離程度有顯著的影響，並對於球速的提升皆有正向效益。

Purpose: This study aimed to investigate whether an intervention using medicine ball training would lead to differences in shoulder-hip separation and ball velocity in adolescent baseball players. Methods: Eighteen adolescent baseball players were recruited and randomly assigned to either experimental or control groups. The experimental group underwent an eight-week, twice-weekly medicine ball training intervention. Angular velocity of shoulder plane, angular of shoulder plane displacement, angular velocity of hip plane, angular displacement of hip plane, shoulder-hip separation angle, peak angular velocity of shoulder plane, peak rotation timing of shoulder plane, peak angular velocity of hip plane, peak rotation timing of hip plane, pitching motion time ,and ball velocity were analyzed using a gyroscope and a speed gun before and after the training intervention. A two-factor mixed-design analysis of variance was used to compare differences between the experimental and control groups before and after the intervention. Results: The results showed that the experimental group had significantly higher ball velocity than the control group after the eight-week medicine ball training intervention (F=18.2, p=.009*); Both groups had significantly greater angular displacement of shoulder plane in the post-test than in the pre-test (F=405, p<.001*; F=53.2, p<.001*), and the experimental group had significantly greater angular displacement of shoulder plane than the control group in the post-test (F=26.9, p<.001*); The experimental group had significantly smaller angular displacement hip plane after the intervention (F=12.9, p=.002*), while the control group had significantly larger angular displacement of hip plane (F=24.28, p<.001*), but there was no difference between the two groups; The difference of shoulder-hip angle was significantly greater in the post-test than in the pre-test for the experimental group (F=432, p<.001*), and was significantly greater in the experimental group than in the control group after the intervention (F=82.1, p<.001*); The pitching motion time showed no significant difference between two groups; The peak angular velocity of shoulder plane was significantly higher in the post-test than in the pre-test for the experimental group (F=33.034, p<.001*), and significantly higher in the experimental group than in the control group after the intervention (F=17.062, p=.001*); The experimental group had significantly higher peak rotation timing of shoulder plane after the intervention (F=34.067, p<.001*), and significantly higher than the control group in the post-test (f=18.512, p<.001*); There was no significant difference in peak angular velocity of hip plane after intervention training ;The peak rotation timing of hip plane in the experimental group was significantly smaller in the post test than in the pre test (F=323.039, p<.001*), and significantly smaller than the control group in the post-test (F=281.339, p<.001*). Conclusion: The results of this study show that medicine ball intervention training significantly improves the degree of shoulder-hip separation when adolescent baseball players pitch, and has a positive effect on the improvement of ball speed.

棒球投擲; 陀螺儀; 肩髖角度差

baseball throwing; gyroscope; difference of shoulder-hip angle