Revista Brasileira de Medicina do Esporte
Print version ISSN 1517-8692
On-line version ISSN 1806-9940
SCHNEIDER, Cláudia Dornelles et al. Effect of the ultra-endurance exercise on oxidative stress parameters. Rev Bras Med Esporte [online]. 2009, vol.15, n.2, pp.89-92. ISSN 1517-8692. http://dx.doi.org/10.1590/S1517-86922009000200001.
Ultra-endurance exercises can cause imbalance between the pro and antioxidant systems, leading to lipid, protein and DNA damage. Nevertheless, some studies evaluating Ironman triathlon found protection to lipids. PURPOSE: To evaluate oxidative stress parameters after a half-Ironman competition. METHODS: Eleven subjects aged 31.1 ± 3.3 yr, body weight 72.4 ± 5.4 kg, height 176.2 ± 4.8 cm, body fat 9.8 ± 3.3 %, VO2máx on run 60.7 ± 6.0 mL/kg/min, participated in this study. The following data were measured: lipid damage by chemoluminescence in erythrocyte and TBARS in plasma, protein damage by plasmatic carbonyls, uric acid and phenolic compounds, as well as the antioxidant enzymatic activity of catalase, superoxide dismutase and glutathione peroxidase in erythrocytes. RESULTS: Reduction in superoxide dismutase (23.24 ± 1.49 to 20.77 ± 2.69 U SOD/mg protein, p = 0.045), and increase in uric acid (40.81 ± 10.68 to 60.33 ± 6.71 mg/L, p < 0.001) were found immediately after the competition. No statistically significant differences were found in catalase and glutathione peroxidase or phenolic compounds. Lipid (TBARS and chemoluminescence) or protein (carbonyl) damage was not observed either. CONCLUSION: These athletes did not suffer oxidative stress, probably due to uric acid and other plasmatic antioxidants release in the plasma.
Keywords : free radicals; uric acid; superoxide dismutase.