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%VO2max) group(n=9) or a high-intensity exercise(HIE, 85%VO2max) 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.

Abstract
 1. Introduction
 2. Methods
  2.1. Subjects
  2.2. Anthropometric measurements
  2.3. Treadmill running test
  2.4. Blood sampling and analyses
  2.5. Statistical analyses
 3. Results
 4. Discussion
 5. Conclusion
 References

• Ju-Yong Bae(Department of Physical Education, College of Arts and Physical Education, Dong-A University) Corresponding author
• Kangeun Ko(Department of Physical Education, College of Arts and Physical Education, Dong-A University)
• Yul-Hyo Lee(Department of Physical Education, College of Arts and Physical Education, Dong-A University)
• Jin-Hee Woo(Department of Physical Education, College of Arts and Physical Education, Dong-A University)
• Hyoung Zoo Ha(Department of Physical Education, College of Arts and Physical Education, Dong-A University)
• Hee-Tae Roh(Department of Physical Education, College of Arts and Physical Education, Dong-A University)