McLeay Yanita, Stannard Stephen, Houltham Stuart, Starck Carlene
School of Sport and Exercise, Massey University, Private Bag 11-222, Palmerston North, New Zealand.
Massey Institute of Food Science and Technology, Massey University, Palmerston North, New Zealand.
J Int Soc Sports Nutr. 2017 Apr 27;14:12. doi: 10.1186/s12970-017-0168-9. eCollection 2017.
Endurance athletes are susceptible to cellular damage initiated by excessive levels of aerobic exercise-produced reactive oxygen species (ROS). Whilst ROS can contribute to the onset of fatigue, there is increasing evidence that they play a crucial role in exercise adaptations. The use of antioxidant supplements such as vitamin C and E in athletes is common; however, their ability to enhance performance and facilitate recovery is controversial, with many studies suggesting a blunting of training adaptations with supplementation. The up-regulation of endogenous antioxidant systems brought about by exercise training allows for greater tolerance to subsequent ROS, thus, athletes may benefit from increasing these systems through dietary thiol donors. Recent work has shown supplementation with a cysteine donor (N-acetylcysteine; NAC) improves antioxidant capacity by augmenting glutathione levels and reducing markers of oxidative stress, as well as ergogenic potential through association with delayed fatigue in numerous experimental models. However, the use of this, and other thiol donors may have adverse physiological effects. A recent discovery for the use of a thiol donor food source, keratin, to potentially enhance endogenous antioxidants may have important implications for endurance athletes hoping to enhance performance and recovery without blunting training adaptations.
耐力运动员容易受到有氧运动产生的过量活性氧（ROS）引发的细胞损伤。虽然ROS会导致疲劳的产生，但越来越多的证据表明它们在运动适应中起着关键作用。运动员中使用抗氧化剂补充剂如维生素C和E很常见；然而，它们提高运动表现和促进恢复的能力存在争议，许多研究表明补充剂会削弱训练适应性。运动训练引起的内源性抗氧化系统上调可使机体对随后的ROS具有更高的耐受性，因此，运动员可能会从通过膳食硫醇供体增加这些系统中受益。最近的研究表明，补充半胱氨酸供体（N-乙酰半胱氨酸；NAC）可通过提高谷胱甘肽水平和降低氧化应激标志物来提高抗氧化能力，并且在众多实验模型中通过与延迟疲劳相关联而具有提高运动能力的潜力。然而，使用这种及其他硫醇供体可能会产生不良生理影响。最近发现使用硫醇供体食物来源角蛋白来潜在增强内源性抗氧化剂，这可能对希望提高运动表现和恢复能力而不削弱训练适应性的耐力运动员具有重要意义。
