The effects of corrective exercise on pitching motion and functional movement in MLB a pitcher - A case study

Abstract

<p>目的：棒球投擲動作為非對稱性的運動，長期專項訓練可能會因過度使用，導致身體左右不對稱，因此本研究透過功能性動作檢測 (functional movement screen, FMS) 評估身體的左右不對稱性、活動度與穩定度，並針對較低分數動作介入訓練，改善身體的動作控制能力並提升運動表現。方法：研究對象為一名美國職棒選手 (年齡 26歲、球齡 16年、參與投手球齡 15年、身高 198公分、體重100公斤，最高層級至3A)，利用FMS七項動作進行評估，並設計訓練處方介入訓練，透過3D動作分析系統及測力板分析，比較訓練前、後的投球動作及球速變化。結果：專項動作前後測結果顯示，球速增快 +5.8%、跨步期時間縮短 -1.2%、手臂上舉期時間縮短 -.15.7%、手臂加速期時間變長 +17.4%、前導腳觸地跨步距離縮點 -3.0%，在三個期別前導腳觸地、肩關節最大外旋以及球離手的骨盆旋轉角度 -8.67%、-5.25%、-7.99%與前導腳髖關節伸展角度 -4.05%、-2.23%、-5.34%前導腳膝關節屈曲角度 -0.01%、-3.92%、-4.44%。骨盆旋轉角速度峰值增加 +0.7%以及前導腳膝關節伸展角度峰值增加 +21.2%。軸心腳地面反作用力峰值在投球方向減少 -2.4%，垂直方向減少 -4.4%。前導腳地面反作用力手臂上舉期峰值在投球方向增加 +6.2%，垂直方向增加+2.6%。而手臂加速期峰值在投球方向增加 +7.9%，在垂直方向增加 +3.7%。結論：選手經訓練介入後，仍然執行平常訓練內容，在未給予額外的投球技術指導情況下，其球速進步專項動作也有所改變，改善身體的控制能力可能有助於投球動力鏈的傳遞。</p> <p> </p><p>Purpose: Baseball pitching is an asymmetric movement. Long-term pitching training may gradually lead to an imbalance in the body because of overuse. Therefore, this study implemented a functional movement screen (FMS) to evaluate bilateral asymmetry, mobility, and stability. Focuses on the movements which had a lower score in FMS, giving intervention to improve their ability to control human behaviors and increase their athletic performance in the study. Methods: The participant is a 26-year-old pitcher pitching in Minor League Baseball who has been playing baseball for 16 years and pitching for 15 years with 198 height and 100kg weight. The highest level is triple-A in his pitching career. The subject’s movement qualities were evaluated by the functional movement screen (FMS) including seven types of motions, and then give interventions with a training program. Additionally, using a 3D motion system and force plates analyze the change of pitching motion and ball velocity before and after the training program. Results: The ball velocity increased +5.8%, the stride period is shorter -1.2%, the arm cocking period is shorter -15.7%, the arm acceleration period is longer +17.4%, the distance of striding is shorter -3.0%.Compare the pre-test and post-test, in stride foot contact, Max ER, and release periods the rotational angle of the pelvis decreased 8.67%, 5.25%, and 7.99% respectively, extensional angle of the pelvis in stride foot decreased 4.05%, 2.23%, and 5.34% respectively, the flexible angle in stride foot decreased 0.01%, 3.92%, and 4.44% respectively. The peak force of GRFs in the pivot foot decreased 2.4% in the pitching direction and 4.4% in the vertical direction. The peak force of GRFs increased 6.2% in the pitching direction and 2.6% in the vertical direction during the arm cocking period. Moreover, the peak force of GRFs increased 7.9% in the pitching direction and 3.7% in the vertical direction during the arm acceleration period. Conclusion: After the intervention, the pitcher’s ball velocity and movement have changed without additional technical guidance, indicating that his body control ability had been improved and that the kinetic chain was smoother than before.</p> <p> </p>