The purpose of this study was to evaluate the effects of acute exercise on respiratory functions, heart-beats, blood pressure, total antioxidative capacity (TAC), oxidative stress index (OSI), lipid hydro-peroxide (LOOHs) and Paraoxonase (PON) in school boys. A sample of 18 male amateur wrestlers are selected for this study. The participants perform exercise regularly at least four times a week and two hours a day. They participated in this study on voluntary basis. Respiratory frequency (RF), force expiratory volume (FEV1), Peak expiratory flow (PEF), heart-beats, (HB) systolic (SBP) and diastolic blood pressures (DBP) measures and blood samples were taken from the wrestlers before and right after the acute exercise programme. Their respiratory frequency, fev1, pef, heart-beats, sistolic and diastolic blood pressure, total antioxidant capacity (TAC), oxidative stress index (OSI), Lipid Hydro-peroxide (LOOHs) and Paraoxonase (PON) levels were measured and assessed. It was found that wrestlers displayed significant increase in respiratory frequency, heart-beats (p less than 0.01) and sistolic blood pressure, TAC, OSI values (p less than 0.05), after the acute exercise compared to the pre-exercise levels. No significant change was observed in peak expiratory flow (PEF), force expiratory volume (FEV1), diastolic blood pressure, lipid hydro-peroxide (LOOHs) and paraoxonase (PON) levels. In this study, it was found that the balance shifted towards oxidative stress due to increased oxidants after the acute exercise programme. In order to reduce such a high oxidative stress and to prevent athletes from its adverse effects, it is necessary to have an antioxidant rich diet before any exercise or to get antioxidant supplements. (Contains 3 tables.)