Acute antioxidant supplementation and performance – Should this be considered

It is well known that a training intervention leads to mitochondrial adaptations with increased skeletal muscle mitochondrial biogenesis and function. Studies have recently indicated that skeletal muscle mitochondrial function is important for athletic performance. During exercise reactive oxygen species are released from skeletal muscle potentially leading to adaptations but maybe also to fatigue. Focus has been on how chronic antioxidant supplementation affects a training adaptation, where some studies are reporting an abolished adaptation. Whether acute antioxidant supplementation could have a positive effect on fatigue and performance is interesting and highly relevant in sports where athletes are competing over several consecutive days or on the same day, with preliminary competitions in the morning and finals in the afternoon, where it is important for the athletes to recover fast. This review provides an overview of the effects of acute antioxidant supplementation and whether it leads to improved performance and/or faster recovery in humans. • Beetroot supplementation seems to have a positive effect in recreational active participants, which is not the case in highly trained athletes. • NAC does not seem to have a beneficial effect on performance and fatigue when given orally. • Polyphenols seems to have a beneficial effect in recreational active participants, which is not the case in highly trained athletes. • Fitness level and age seems to be important in relation to the effects of acute oral antioxidant supplementation on performance and fatigue.