IMPLICATION OF RELATIONSHIP BETWEEN OXIDATIVE STRESS AND ANTIOXIDANT STATUS IN BLOOD SERUM.

: Aim of the study was to examine the relationship between oxidative stress and overtraining syndrome in athletes by evaluation in serum oxidative and antioxidant status. In 43 athletes with non-functional overreaching (NFO)/overtraining syndrome(OTS) and 40 athletes without NFO/OTS -control athletes (CA), diacron-reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP) in serum, as well as ratio of d-ROMs and BAP test measurements - marker of oxidative stress, were assessed. Baseline data collection performed in both groups of athletes - with NFO/OTS and CA, followed by data collection in athletes with NFO/OTS after 28 days of rest. In athletes suspicious for OTS all measurements were performed after 2 more months of rest. Results of the study showed higher baseline d-ROMs in NFO/OTS athletes than in athletes without NFO/OTS, whereas antioxidant potential in CA was significantly higher, than in NFO/OTS athletes, After 28 days of rest there was significant decrease in d-ROM values in both: athletes with NFO and with OTS, as well as normalization of antioxidant status in athletes with NFO. Total 3 month of rest showed improvement in the oxidative status of athletes with OTS, reaching normal values, though antioxidant status remained without significant improvement, showing subnormal BAP values and decreased BAP/d-ROM ratio. The results demonstrate increased oxidative stress in overtraining state, creating disbalance between d-ROM production and antioxidant capacity. Thus, prolonged imbalance between oxidant production and antioxidant protection via attenuation of antioxidant capacity can be a cause of overtraining in highly trained athletes. In this study most frequently NFO and OTS were seen in wrestling, which needs further investigation and regular medical monitoring.