The purpose of the present investigation was to determine the effect of various periods of endurance and sprint training on lipid peroxidation (Malondialdehyde) and antioxidant defence system including Ferric Reducing Ability of Plasma (FRAP), Bilirubin, Uric acid and Total protein. Methodology. A total of 54 three month old rats were selected for this purpose and they were randomly assigned to three groups of endurance training (n=18), sprint training (n=18), and control group (n=18). The rats in the experimental conditions performed an either an endurance or sprint training program for 12 weeks, three time a week. The training protocols were designed based on oxygen cost ( intensity of the endurance training was set at %70-80, while for the sprint training group was set to %100 vo2max). The variables of interest were measured at three intervals using kit (bilirubin, UA and TP), TPTZ reagent (MDA) and Thiobarbituric acid marker (FRAP).Results and conclusion. The results of analysis by using of Two way repeated ANOVA showed that no significant changes occurred within the control condition, where as , considering MDA , bilirubin and uric acid in endurance training group and based on MDA , FRAP, bilirubin and uric acid within the sprint training group significantly changed. Also, the type of training (sprint vs. endurance) had a significant effect on FRAP (p=0.001) and bilirubin (p=0.000), while no significant changes was found for MDA, uric acid or total protein. In summary, the findings of this research indicated that participation in regular endurance or sprint training program leads to the improvement of antioxidant defence system that prevent increase in lipid peroxidation, that to be agreement with other studies(1,2). Thus, contrary to the paradox that exercise training increases free radicals, it is well know that regular exercise training cause improvement in health condition(2). 1- Alessio H.M, FACSM, Nagy S, Byrnes R, Philip B,Hagerman AE,Wiley RL (2002). Ef
