目的：本研究主要探討當高爾夫選手以不同桿頭速度擊球時其軀幹旋轉的變化情形，藉以討論桿頭速度與軀幹旋轉模式之相對關係。方法：本實驗共招募10名高爾夫選手為受詴者，並分析每位選手揮桿之桿頭速度及軀幹旋轉參數。受詴者參與揮桿實驗分別以平日正常擊球的桿頭速度揮桿及以比平時揮桿更快的方式來揮桿擊球。三度空間座標資料透過紅外線攝影系統收集，並將三度空間座標資料轉換成軀幹旋轉參數 (上半身旋轉角度、骨盆旋轉角度、上半身側彎角度、骨盆側彎角度、骨盆前傾角度與X因子) 來進行分析。以相依樣本t檢定比較桿頭速度正常、增加兩種擊球方式下軀幹旋轉參數的差異。結果：實驗結果發現在桿頭速度改變的同時，軀幹的旋轉模式也為之調整：在增加揮桿擊球時，骨盆在準備時有較大的前傾角度，在上桿時有較大的上半身旋轉角度及骨盆前傾角度，當到達上桿頂點處則有較大的骨盆側彎角度，在下桿時有較小的骨盆旋轉角度及較大的X因子，在觸球瞬間有較大的上半身旋轉角度、較大骨盆旋轉角度及較大的X因子，最後在送桿的時候，出現較大的骨盆旋轉角度與較大的X因子。結論：高爾夫選手為改變桿頭揮擊速度，藉由調整軀幹的旋轉模式來達到目的，對於追求提升距離的球友或練習生而言，是值得參考的動作模式。

Purpose: This study investigated the relationship between golf swing motion and trunk rotation patterns while swing at different club head speed. Methods: Ten golfers (age: 16.9 ± 3.5 years, handicap: 4.5 ± 3.17) were recruited to join this experiment and asked to swing at two club head speeds: normal and accelerated club head speed. The club head speed was recorded by Auditor Speed Check device. Trunk rotation patterns (upper trunk rotation angle, pelvic rotation angle, upper trunk side-bend angle, pelvic side-bend angle, pelvic tilt angle, and X Factor) were collected by 3D Vicon Motion Capture System (250Hz). A paried t test was employed to compare the differences of trunk rotation patterns between normal and accelerated club head speed. Significant level was set at 0.05. Results: Several significant differences were found between normal and accelerated club head speed. Since the address phase, swung at the accelerated club head speed, a significant greater pelvic tilt angle was found. When swung at the accelerated club head speed, a greater upper trunk rotation angle and pelvic tilt angle at following backswing phase were demonstrated. In addition, during downswing phase, a significant smaller pelvic rotation angle and a larger X Factor were found with the accelerated club head speed. Accelerated club head speed swung also illustrated greater upper trunk rotation angle, greater pelvic rotation angle, and greater X Factor at the ball impact phase. Ultimately, swung at the accelerated club head speed had greater pelvic rotation angle and X Factor than normal club head speed swing at the follow through phase. Conclusions: We concluded that golfer would change their trunk rotation pattern to accelerate club head speed. For coaches and golfers, adjusting the correct trunk rotation patterns would be a method to increase the ideal club head speeds.