The Effect of Aerobic Exercise on Oxidative Stress in Elite Swimmers and Sedentaries and the Investigation of Pon1 Gene Polymorphism

In this study, the aim was to compare the levels of oxidative stress and antioxidant defense system occurred in elite swimmers and sedentaries after aerobic exercise and to investigate PON1 gene polymorphism. The study was conducted on 15 elite swimmers and 15 healthy sedentary men between the ages of 18-23 who make regular training. One-time aerobic exercise test was applied to both of the groups. Maximal oxygen consumption capacity (VO2 max) of individuals was determined by using gas analysis system. Submaximal aerobic exercise test in intensity of 75% of VO2 max was applied to each subject. Malondialdehyde (MDA), catalase (CAT) activities, and paraoxonase (PON1) gene enzyme activities were detected in blood samples taken from subjects before and immediately after exercise. PON1 gene polymorphisms were investigated in blood samples taken at rest. In the study, a significant increase in MDA, CAT and PON1 enzyme activities (p < 0.01) in swimmers subjected to aerobic exercise in intensity of 75% of VO2 max and significant increase in MDA and PON1 activities and significant decrease in CAT activity (p < 0.01) in sedentaries were detected. Significant correlation was found between the groups in the comparison of the differences (p < 0.01). Genotype distributions were detected as QQ (46.7%), QR (40.0%) and RR (13.3%) in swimmers and QQ (40.0%), QR (53.3%) and RR (6.7%) in sedentaries in our study. As a result, it was considered that aerobic exercise caused oxidative stress by producing a large amount of free radicals and this was related to the severity and duration of exercise affecting the balance between free radicals and antioxidant system. It is thought that the effect of aerobic exercise on PON1 activity levels is related with the availability of regular sports activities and this is directed by PON1-192 polymorphism.