Plasma protein-bound sulfhydryl group oxidation in humans following a full marathon race.

Physical exercise can induce oxidative stress in humans. We studied the influence of aerobic exercise on the status of plasma protein-bound sulfhydryl groups in seven moderately-trained male college students who participated in a full marathon race. The plasma protein-bound sulfhydryl group values were significantly declined immediately after the race (-22%, p < 0.01), and 24 h (-12%, p < 0.01) and 48 h (-13%, p < 0.01) after the race, as compared to the baseline value. The plasma concentrations of thiobarbituric acid reactive substances were unchanged following the race, while the activities of plasma creatine kinase were significantly increased, indicating skeletal muscle damage. These results suggested that prolonged exercise may cause the oxidation of plasma proteins.