本研究主要目的在於探討衰竭運動與肌纖維類型對超氧化物岐化峙的影響。實驗中以50隻雄性的白老鼠If?受試對象，隨機分配至衰竭運動組與控制組。衰竭運動組的老鼠在老鼠跑步機上以每小時2缸里、陡度15%的快速、高陡度運動強度跑至衰竭鳥止。衰竭運動後取出老鼠右後腿的比目魚肌、蹄、肌、排腸肌紅肌..g�與牌腸肌白肌部f控制組的老鼠亦在同一時間取出上述肌纖維。超氧化物岐化峙的含量是採用McCord& Fridovich的方法來測量。所得 的數據是以二因于重複量數變異數分析來考驗衰竭運動與肌纖維類型對超氧化物岐化峙的影響。結果顯示，衰竭運動促使老鼠骨路肌的超氧化物岐化鷗顯著土升。本研究採取的四種肌纖維的超氧化物岐化鷗對於衰竭運動的反應並不一致。但是老鼠紅肌(比目魚肌、胖腸肌紅肌部)中的超氧化物岐化鷗在衰竭運動的情況下，顯著高於控制組的超氧化物岐化峙;至於白肌(蹄J)Jt、排腸肌白肌部)的超氧化物岐化鷗對於衰竭運動的反應，與控制組就沒有顯著的差異存在。因此，本研究認為衰竭運動產生了氧化壓力，使老鼠骨駱肌增加超氧化物岐化峙的含量以為因應;然而因肌肉類型不同，生化特性有剖，徵召型態亦有差異，故而使紅肌的超氧化物岐化鷗含量比白肌更能顯著提升。

The purpose of this study was to investigate the effects of exhaustive exercise and muscle fiber type on superoxide dismutase (SOD). Fifty male rats were randomly divided into the following two groups: l)exhaustiveexercise，and 2)control group (n=25). Thestrenuous exercise was performed on a rodent treadmill at a speed of 2 Km/hup a 15% grade until exhaustive.The soleus， plantaris， and red and white gastrocnemius muscles of the rat right hindlimb were removed following exhaustive exercise. Control rats were sacrificed at the same time as the exhaustive exercise group. TheSOD activity was determined using the method of McCord& Fridovich. Two way repeated measure ANOV A was performed to examine the effects of exhaustive exercise and muscle fiber type on SOD. :Thefinding showed that exhaustive exercise resulted in a singificant increase in SOD activity of rat skeletal muscle. Therewas no identical alteration among 4 kinds of fiber types on SOD activities in response to exhaustive exercise. Moreover， the activity of SOD induced by exhaustive exercise on red fiber (soleus and red gastrocnemius) was significantly higher than control group， while SOD activity on white fiber (plantaris and white gastrocnemius) was not significant different between exhaustive exercise and control group. It was concluded that exhaustive exercise could result in oxygen free radical stress. Thehigher SOD activity in red fiber during exercise may be due to fiber type difference， biochemical property， and fiber pattern recruited.