流行病學及臨床研究指出運動不但能增強骨骼肌及心血管功能，還可改善大腦的認知功能。但運動訓練是否可以改善小腦功能則仍未知。因此本研究欲探討運動對小腦功能的影響。將五週齡雄性Wistar大鼠隨機分為運動組及對照組; 運動組接受八週的中等強度跑步機運動訓練。對照組則不運動。運動訓練結束後，大鼠接受動作協調及平衡能力之行為測試，然後犧牲以取得不同部位的腦組織。以西方點墨法分析各腦區粒線體相關蛋白質的表現，包括Mfn2、OPA1、Drp1和CcOx-IV。結果顯示運動訓練可以改善動作協調及平衡能力，並增加小腦Mfn2和OPA1 (粒線體融合蛋白) 蛋白質表現，但不影響Drp1 (粒線體分裂蛋白)和CcOx-IV (粒線體complex IV)的蛋白質表現。反之，運動訓練並不影響其他腦區粒線體蛋白質的表現，包括感覺皮質區、下視丘前區/後區、海馬迴和杏仁核。為了研究運動是否能改善小腦抵抗毒素所引發之損傷，於運動訓練五週後將OX7-saporin (小腦Purkinje cell毒素)注射至大鼠之側腦室，再繼續運動訓練三週。八週運動訓練完後評估其小腦功能。研究結果發現注射OX7-saporin顯著損害對照組之動作協調及平衡能力，並降低小腦蚓部(特別是在第二、三、五、六和九小葉)和小腦半球(除Crus1小葉外)的Purkinje細胞數目。OX7-saporin對運動組卻未造成明顯的傷害。綜合上述，運動訓練可以改善小腦功能，包含動作協調及平衡能力、粒線體融合蛋白質表現以及對外來毒素的阻抗能力。

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