The Effect of Antioxidant Supplementation on Fatigue during Exercise: Potential Role for NAD+(H)

This study compared serum pyridine levels (NAD(+)/NADH) in trained (n = 6) and untrained (n = 7) subjects after continuous progressive exercise at 50%, 70% then 95% of physical work capacity until fatigue (TTF) after consuming a placebo or antioxidant (AO) cocktail (Lactaway (c)). An increase of 17% in TTF was observed in AO as compared to placebo (p = 0.032). This was accompanied by a significant increase in serum NAD(+) levels (p = 0.037) in the AO supplemented group post exercise. The increases in NAD(+) and improved endurance reflect lower oxidative stress-induced suppression of aerobic respiration.