Effect of different exercise intensities on biomarkers of oxidant-antioxidant balance, inflammation, and muscle damage

We investigated the effect of different exercise intensities on biomarkers of oxidant-antioxidant balance, inflammation, and muscle damage. Eighteen healthy and untrained male subjects were enrolled.Subjects were randomly and equally assigned to a moderate-intensityexercise(MIE, 65%VO 2 max) group(n=9) or a high-intensity exercise(HIE, 85%VO 2 max) group(n=9).Blood samples were collectedimmediately pre-exercise, post-exercise, and 60min post-exercisetoexamine oxidant-antioxidant balance(d-ROMs; BAP), inflammation(CRP; fibrinogen), muscle damage(CK; LDH), and lactate. Serum d-ROMs and BAP levels were significantly increased post-exercise compared with pre-exercise levels in HIE group(p<0.05). Lactate levels were significantly increased post-exercise compared pre-exercise levels in both the MIE and HIE groups(p<0.05). In addition, post-exercise serum d-ROMs and plasma lactate levels were significantly higher in the HIE group than in the MIE group(p<0.05). These results suggest that although relatively high-intensity exercises may increase oxidative stress levels in the body, they do not produce inflammatory response and/or muscle damage.