對於長期慢跑的人而言，跑步時足後部接觸地面的過度外翻與足部傷害的關係很大，而從慢跑鞋的改良上，可以有效的控制足後部的外翻情形。本研究的目的在於比較赤足與穿鞋跑步時：（一）地面接觸期前10%阿基里斯腱的平均角速度；（二）地面接觸期阿基里斯腱外翻角度的最大變化值之間的差異，並探討本研究使用的慢跑鞋在設計上的問題。以16 名男性受試者分別赤足與穿鞋在跑步機以3.5 m/s 的速度進行測試，用高速攝影機125 f/s 從正後方拍攝。得到的結果為：穿鞋跑步時在地面接觸期前10%阿基里斯腱的平均角速度比赤足跑步時增加（p<.05）；穿鞋跑步時在地面接觸的阿基里斯腱外翻角度的最大變化值比赤足跑步時增加（p<.05）。本研究使用的慢跑鞋，並無法改善跑步時足後部外翻的情形。因此發現：（一）在鞋子底墊後部外側的設計上要比較圓滑，以減少足後部外側接觸地面時足部所形成的力矩。（二）必須在鞋子底墊的後部內側增強硬度及加強鞋內足弓處的穩固性，以減少鞋子變形的程度及足部與鞋子之間的相對運動，適度的保護足部。

The purpose of this study was to compare the differences of barefoot and shod-foot during running in the following 2 aspects: (1) average angular velocity of achilles tendon on the first 10% of ground contact; (2) the difference of maximum variety about the pronation angle of achilles tendon on ground contact, and explore any problems related to the design of the running shoes used in this experiment. Sixteen male runners participated voluntarily in this study. The high-speed video camera was operated at 125Hz and was used to record the participants when they are performing the treadmill 3.5m/s. Two findings are: (1) the rear outside shoe sole must be tactful in order to decrease the torque when outside rearfoot contacts the ground; (2) the strength at the cushioning of shoe sole and the stability of the arch of foot must be increased in order to minimize the degree of deformation and relative-motion between the foot and shoe and to protect foot.