本研究之主要目的在探討不同強度阻抗運動對肌酸激?t（creatine kinase,CK）與丙二醛（ malondialdehyde, MDA ）之影響。受試者為 20 名男性學生，平均年齡 21.20± 1.40 歲，身高 175.05 ± 6.66 公分，體重 71.50 ± 8.19 公斤。 本研究採重複量數設計， 以隨機方式讓受試者分別接受美國運動醫學會（ ACSM ）推薦負荷強度之 8RM 與15RM， 訓練的阻抗運動項目為：仰臥推舉（ bench press ）、蹲舉（ half squat ）、臂屈（ arm curls ）、 大腿伸踢（ leg extension ）、正握拉槓（ latpulldown ）、腿背彎舉（ leg curls ）、仰臥起坐（ sit-up ）、 負槓前跨（ front dumbbell lunge ）等八項。 實施阻抗運動時，每次完成三組，組間休息 2 分鐘。不同強度之間測驗的間隔時間為 7 天。 受試者在運動前與運動後瞬間、運動後 24 小時及 48 時抽血分析血液中肌酸激?t與丙二醛的濃度。結果發現在 8RM 運動後 48 小時，CK 值明顯高於安靜值，不同強度的CK 值，則 8RM 的 CK 值比 15RM 的 CK 值高； 而 MDA，在 8RM 和 15RM 運動後瞬間及運動後 24 小時皆有顯著上升， 8RM 與 15RM 則無明顯差異存在。 本研究結果顯示，8RM 與15RM 間的阻抗運動，造成骨骼肌相當衝擊與氧化壓力。

　　　　　The purpose of this study was to evaluate the effect of differentintensity resistance on creatine kinae and malondialdehyde. Twenty (20) malecollege students were recruited from the NTNU. All subjects (age=21.6 ±1.65yrs, ht=178.50 ± 6.59cm, wt=74.70 ± 7.68kg) in both groups participated in8RM and 15RM resistance exercise (including bench press, half squat, arm curls,leg extension, lat pull-down, leg curls, sit-up and front dumbbell lunge) inbalanced order. The blood samples for malondialdehyde (MDA), creatine kinase(CK) determination were taken before exercise, immediately, 24 h and 48 hpostexercise from the antecubital vein. The data was analyzed by two-way ANOVAwith repeated measures. The results were as follows: CK activity in 8RM wassignificantly elevated at 48 h after exercise. The CK values significantlyhigher in the 8RM than 15RM. Serum MDA concentration was significantly elevatedafter exercise and 24 h after exercise. No significant difference in MDA levelswas found between 8RM and 15RM intensities. Conclusion: The MDA activities ofboth groups were significantly elevated after exercise and 24 h after resistanceexercise. Results from this study indicate that both of 8 RM and 12 RMresistance exercise induce somewhat tissue damage and oxygen stress on skeletonmuscles.