The effect of endurance training on prevention of harmful effect of oxidative stress induced by exhaustive exercise in rats

Different protocols of exercise cause different oxidative status. Regular exercises could act like vaccination and up regulate antioxidant systems in body. So 40 male Wistar rats with body weight (154±2 gr) were divided into two groups: 1) trained (n=20) and 2) untrained groups (n=20) at random. Training group participated in eight weeks training program, 5days per week, consisted of treadmill running that began speed was 8 m/min for 10 min and with gradually increase in speed and time reaching the speed of 30 m/min for 1.5 h/day at 8th week.At the end of 8 week each group further divided in to groups where the rats were studied at rest and after exhaustive exercise. For acute exhaustive exercise graded treadmill running was conducted reaching the speed of 35 m/min and was continued until exhaustion, then animals were anesthetized and blood sample were collected for measurements of catalase activity in red blood cell by Abei method and plasma MDA was estimated by spectrophotometry and total antioxidant capacity (TAC) measured by Ferric reducing antioxidant power (FRAP). These results indicated that acute exhaustive exercise increased the MDA level in sedentary but not in trained rat. The catalase activity was elevated significantly in trained group but was unchanged by exhausting exercise and TAC increased in exercise group after exhaustive exercise but decreased in just one session exhaustive group. We conclude that exhaustive exercise induced oxidative stress but endurance training may be useful for preventing acute exhaustive exercise induced oxidative stress by up-regulating antioxidant enzyme activity.