Tabriz University of Medical Sciences Pharmaceutical Sciences 1735-403X 18 3 2012 10 02 Effects of Caffeine Supplementation on Oxidative Stress, Exercise-Induced Muscle Damage and Leukocytosis 177 182 EN Reza Mahdavi Sevana Daneghian Aziz Homayouni Afshar Jafari Journal Article 2012 05 16 Athletes use variety of ergogenic aids such as caffeine to improve their performance. Many factors such as oxidative stress, muscular-damage and decreased immune function may have negative effect on athletic performance. However effects of caffeine on mentioned factors in female athletes after supramaximal exercise are rare and obscure. Methods: In this double-blind, cross-over study, 26 female basketball players supplemented with 5mg.kg-1 caffeine or dextrose as a placebo followed by Wingate test. Blood samples were obtained before and 5 minutes post-exercise for determining the serum malondialdehyde (MDA), total antioxidant capacity (TAC), creatine kinase (CK) activity and blood’s white blood cells (WBC). Kolmogrov-smirnov statistic test and paired t-test were used to analyze data. Results: After the Wingate test, WBC, lymphocyte, granulocyte count and serum MDA levels, were increased significantly in both groups(P<0.001). No significant differences were observed in increased levels between caffeine supplemented and placebo groups(P>0.05). Furthermore the changes in CK activity and TAC levels were not statistically significant in any of the groups (P>0.05). Conclusion: The findings indicated that 5mg.kg-1 caffeine supplementation did not have significant adverse effect on oxidative stress, exercise-induced muscle damage and leukocytosis after Wingate test.