本研究目的在於探討不同下肢動作範圍膝關節伸肌等速向心肌力最大力矩與下蹲跳表現之相關。25位國立台灣師範大學體育系男性自願參與本研究，每位受試者於Cybex6000等速測力儀分別測試5次最大努力之90°~60°、90°~30°、90°~0°等三種不同動作範圍，相同角速度120°/s下的等速向心肌力，及利用Kistler測力板測驗下蹲跳之表現。以皮爾遜積差相關分析膝關節等速伸肌最大力矩與下蹲跳之相關，顯著水準設為a=.05。本研究得到90°~60°、90°~30°及90°~0°等三種不同動作範圍平均最大力矩分別為156.2Nm±38.17、160.5Nm±36.01、165.6Nm±44.27，下蹲跳平均最佳高度為46.2cm±3.39。結果發現90°~60°ROM之最大力矩與下蹲跳呈顯著相關(r=.046, p<.05),90°~30°ROM之最大力矩與下蹲跳呈顯著相關(r=.346, p<05)，但90°~0°ROM之最大力矩卻與下蹲跳無顯著相關(r=.046, P>.05)。本研究結果顯示30°與60°ROM之膝關節等速向心肌力與下蹲跳表現有顯著相關，其中以90°~60°ROM之相關較高，故可推論，在進行此跳躍動作時，下蹲之角度範圍於30°左右，可產生較佳的跳躍表現，且90°-60°動作範圍之等速向心肌力可作為評估下蹲跳的參考依據。

The purpose of this study was to determine the relationship between isokinetic strength of the knee extensors at different range of motion and jump performance. Twenty-five subjects participated in this study. All subjects performed five maximal knee extensor efforts at angular velocity of 120º/s under three range of motion (90º~60º, 90º~30º, 90º~0º) on Cybex6000 Dynamometer. The subjects also performed counter-movement jump on Kistler9287 force platform. Pearson Product Moment Correlation analyses were conducted to determine the relationship between isokinetic strength and jump parameters. The significance level was set at α=.05. The average torque at 90º~60º, 90º~30º and 90º~0º of range of motion were 156.2Nm±38.17, 160.5 Nm±36.01, 165.6 Nm±44.27, respectively. The average jump height was 46.2±3.39. These correlation coefficients of isokinetic strength at three range of motion and jump performance were r=.406(p<.05), r=.346(p<.05), r=.046(p>.05), respectively. In conclusion, the results of this study indicated there are significant relationships between isokinetic strength at two range of motion (90º~60º & 90º~30º) and jump performance.