Purpose: To thoroughly investigate the time-course changes of several commonly used markers of oxidative stress by performing serial measurements during a 24-h period after an acute bout of strenuous cardiovascular exercise.
Methods: Eleven untrained men performed two trials. In the experimental trial, the subjects exercised for 45 min at 70-75% V˙O2max and then at 90% V˙O2max to exhaustion on a treadmill; in the control trial, the subjects remained at rest. Blood samples were drawn before and after exercise (immediately after exercise and at 0.5, 1, 2, 3, 4, 5, 6, 8, 10, and 24 h). Reduced glutathione (GSH), oxidized glutathione (GSSG), GSH/GSSG, thiobarbituric acid-reactive substances (TBARS), protein carbonyls, catalase activity, and total antioxidant capacity (TAC) were determined.
Results: The time to lowest concentration after exercise was 1.7 ± 0.7 h (mean ± SD) for GSH/GSSG, and the time to highest concentration after exercise was 1.2 ± 0.6 h for TBARS, 4.4 ± 0.5 h for protein carbonyls, 0.5 ± 0.4h for catalase, and 2.2 ± 0.9 h for TAC. The greatest change after exercise was −74 ± 9% for GSH/GSSG, 129 ± 29% for TBARS, 135 ± 53% for protein carbonyls, 51 ± 16% for catalase, and 24 ± 10% for TAC.
Conclusion: There is no best time point applying to all markers for collecting blood samples after aerobic exercise. The optimum postexercise time points for blood collection in untrained individuals are immediately after exercise for catalase, 1 h for TBARS, 2 h for TAC, GSH, and GSSG, and 4 h after exercise for protein carbonyls.
1Department of Physical Education and Sport Science, Democritus University of Thrace, Komotini, GREECE; 2Department of Physical Education and Sport Science, University of Thessaly, Trikala, GREECE; 3Institute of Human Performance and Rehabilitation, Centre for Research and Technology-Thessaly, Trikala, GREECE; 4Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, GREECE; 5School of Sport, Performing Arts and Leisure, Wolverhampton University, Walshall, UNITED KINGDOM; and 6Department of Clinical Biochemistry, Aghia Sophia Children's Hospital, Athens, GREECE
Address for correspondence: Dimitris Kouretas, Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, 41221, Greece; E-mail: email@example.com.
Submitted for publication December 2006.
Accepted for publication February 2007.