Concomitant assessment of DNA oxidation and bone resorption over a rapid body mass reduction period in female judokas

Abstract

The purpose of this study was to concomitantly determine oxidative DNAdamage and bone resorption following a rapid body mass reduction in association with energy restriction and exercise training, considering 17β-estradiol level, in female collegiate judokas. Eighteen nationally ranked university female judokas were enrolled as participants in this study. All participants continuously managed to reduce their body mass 8 days just before a competition. To detect cumulative effects of oxidative DNA damage and bone resorption, urinary samples were collected in the morning on three different days (Day 1= the beginning of body mass reduction; Day 4=mid-term of body mass reduction; Day 7=the day before the competition) for the later analysis of 8-hydroxy-2- deoxyguanosine (8-OHdG) as well as cross-linked N-terminal telopeptides of Type I collagen (NTx). Urinary 8-OHdG and NTx levels were determined with high performance liquid chromatography and enzyme-linked immunosorbent assay, respectively. No significant alterations were observed in urinary 8-OHdG or NTx levels over a rapid body mass reduction period. The findings of the present study indicate that female judokas appear to have relatively less oxidative DNA damage determined by quantification of 8-OHdG and bone resorption over a rapid body mass reduction period, potentially due to the enhanced endogenous defense responses (training adaptation). These data can provide athletes and coaches with valuable information in considering an optimal body mass management program to avoid detrimental physiological and biological conditions.