BACKGROUND The aim of the present study was to investigate the effect of alpha-tocopherol (alpha-Te) supplementation on DNA oxidative damage induced by heavy training in basketball players. METHODS Blood was obtained from 10 players before (group A) and after training (group B) and after 1 month on alpha-Te (200 mg/day, orally) supplementation, before (group C) and after training (group D). Total antioxidant status (TAS), muscle enzyme activities and the biomarker of DNA oxidation, 8-hydroxy-2-deoxyguanosine (8-OHdG), were measured using commercial kits. alpha-Te and catecholamine blood levels were determined using HPLC methods. RESULTS TAS was higher in the groups with alpha-Te (groups C and D). Levels of 8-OHdG and muscle creatine kinase (CK) and lactate dehydrogenase (LDH) were remarkably lower (0.20+/-0.03 ng/mL, 120+/-15 U/L and 430+/-90 U/L, respectively) in the group with alpha-Te (group D) than in group B (0.42+/-0.05 ng/mL, 286+/-12 U/L and 688+/-88 U/L, respectively; p<0.001). 8-OHdG levels were negatively correlated to TAS and positively to CK levels. CONCLUSIONS alpha-Te supplementation may reduce DNA oxidation induced by training by protecting muscle cell "death" from glutamate entry and/or by elevation of TAS via amelioration of lipid peroxidation.