MEDICAL GAS

Full list of author information is available at the end of the articlespecies (ROS) and reactive nitrogen species (RNS) also increase, threatening to disturb redox balance and cause oxidative stress. During normal conditions, ROS and RNS are generated at a low rate and subsequently elimi-nated by the antioxidant systems. However, a greatly increased rate of ROS production may exceed the cap-acity of the cellular defense system. Consequently, trained athletes suffer from less oxidative stress reduc-tion because their antioxidant systems adapt, accumula-tion of intense exercise can provoke an increase in oxidative stress [4]. To mitigate oxidative stress-induced adverse events during sports, antioxidant supplementa-tion among athletes has been well documented. Al-though results of these studies are often contradictory depending on the antioxidant compounds and quantity, some studies demonstrate the beneficial effects of anti-oxidants on muscle fatigue or performance [5,6]. * Correspondence