Comparison of the Oxidative Stress and Antioxidant Levels of the Endurance Athletes After Maximal and Submaximal Exercise

The purpose of this study was to compare the oxidative stress and antioxidant levels of the endurance athletes after maximal and submaximal exercise. In this study total of 20 male subjects who voluntarily participated (10 sedentary university students and 10 endurance athletes). Mean Max VO2 capacity was 69.50±8.19 ml/kg/min and mean age was 19.30±1.64 yrs old for endurance athletes and respectfully 34,15±8.08 ml/kg/min and 19.70±1.16 yrs old for sedentary. Max VO2 levels of subjects were determined by Bruce Protocol. The subjects performed their submaximal exercise with intensity of 70% of Max VO2 during 30 minute period. Maximal exercise with intensity of 100% of Max VO2 was executed until they were exhausted. Blood samples of subjects were collected before and after exercise to analyse plasma Malondialdehit (MDA), Total sülfhidril group (RSH) and Nitric oxide (NOx) levels. The results indicated that there were no significant differences among levels of MDA and NOx parameters between pre-submaximal and post-submaximal exercise in endurance athletes and control group (P 0.05). Only there was significant difference the level of RSH parameter between pre-submaximal and post-submaximal exercise for control group (P 0.05). Before and after maximal exercise, MDA and NOx levels were found significantly different for sedentary and endurance subjects (P 0.05). There were significant differences among levels of MDA, RSH and NOx parameters between post-submaximal and post-maximal exercise for two groups (P 0.05) and these variables increased after maximal exercise. There were also no significant differences in RSH parameters. Also, there were significant differences among BMI scores (P 0,05), MaxVO2, KAHrest and KAHmax of the endurance athletes and sedentary (P 0,001). Consequently, submaximal exercise could be healthy practice for humans; however, maximal exercise could trigger occurring of free radicals. This could be evidenced by increasing in lipid peroxidation and oxidative stress during maximal execise. Thus, the intensity of exercise could be very important to definition of the accumulation of free radicals for sedentary and endurance athletes.