Experimental guidelines for studies designed to investigate the impact of antioxidant supplementation on exercise performance.

Research interest in the effects of antioxidants on exercise-induced oxidative stress and human performance continues to grow as new scientists enter this field. Consequently, there is a need to establish an acceptable set of criteria for monitoring antioxidant capacity and oxidative damage in tissues. Numerous reports have described a wide range of assays to detect both antioxidant capacity and oxidative damage to biomolecules, but many techniques are not appropriate in all experimental conditions. Here, the authors present guidelines for selecting and interpreting methods that can be used by scientists to investigate the impact of antioxidants on both exercise performance and the redox status of tissues. Moreover, these guidelines will be useful for reviewers who are assigned the task of evaluating studies on this topic. The set of guidelines contained in this report is not designed to be a strict set of rules, because often the appropriate procedures depend on the question being addressed and the experimental model. Furthermore, because no individual assay is guaranteed to be the most appropriate in every experimental situation, the authors strongly recommend using multiple assays to verify a change in biomarkers of oxidative stress or redox balance.