目的：探討在橢圓機在不同坡度(0%、5%、10%、15%、20%)上進行踩踏運動時，對運動經濟性與下肢運動軌跡及關節角速度的差異。方法：15位大學生為研究對象（年齡22.60±2.80歲、身高174.6±4.31公分、體重69.67±9.65公斤），以60rpm，無踏板阻力條件下，進行五個不同坡度的橢圓機踩踏運動。每個坡度踩踏三分鐘（間隔休息10分鐘），研究紀錄第三分鐘穩定之攝氧量及二維攝影20秒運動軌跡。資料以單因子重複量數變異數分析比較不同坡度的攝氧量、心跳率與下肢關節角速度之差異。結果：攝氧量方面，各坡度間達顯著差異(p<.05)，發現以15%(30.03±4.13ml/kg/min)坡度時平均攝氧量最低，且坡度20%(31.33±3.54ml/kg/min)時攝氧量顯著大於坡度15%、10%(30.21±3.32ml/kg/min)。在心跳率方面，各坡度間亦達顯著差異(p<.05)，發現以10%(139.77±16.20bpm)坡度時平均心跳率值最低，且坡度0%(144.49±16.47bpm)時心跳率顯著大於10%(139.77±16.20bpm)。下肢關節角速度方面，髖關節、膝關節之角速度變化量皆隨著坡度上升而增加。踝關節角速度變化量與坡度呈反比。結論：在橢圓機五種坡度(0%、5%、10%、15%、20%)上，運動經濟性會隨著坡度增加呈現先增後減之現象，且在10%、15%坡度時有較佳之運動經濟性。而髖關節、膝關節角速度變化量隨著坡度上升而顯著增加，但踝關節角速度變化量則隨著坡度上升顯著下降。

Purpose: The purposes of this study was to evaluate the effects of different gradient (0%, 5%, 10%, 15%, 20%) elliptical trainer exercise on the track of lower extremity and physiological response. Methods: Fifteen volunteer subjects underwent the trial of 60rpm, composed of five different gradient elliptical trainer exercises. Each exercise trail was three minutes and each exercise trail. Kinematics was calculated for twenty seconds. One-way ANOVA were employed to analyze these data. Results: Oxygen uptake, the various gradient did not reach significant difference (F=.429, p=.787>.05), but the averages for comparison and found the gradient of 10% (29.75±3.31ml/kg/min) and 15% (29.95±4.12ml/kg/min) had lower oxygen uptake value, exercise economy were better. In kinematics, with the gradient rise, the hip joint, knee joint of the angular velocity were appeared. The angular velocity variation of ankle joint appears inverse proportion with gradient. Conclusions: The adjustable gradient of elliptical did not showed the significant difference on the oxygen uptake of forward trial that with the increase of gradient, the first step on exercise economy would increase first than decrease. Middle-gradient exercise economy is much better and suitable for body's natural gait, even more for those with fitness.