Controversies of antioxidant vitamins supplementation in exercise: ergogenic or ergolytic effects in humans?

Abstract

The aim of this commentary was to discuss the last studies regarding the effect of antioxidant vitamins supplementation on oxidative stress in exercise in humans. The inclusion criteria encompassed published studies done in adult males and females between 2006 and 2013. The keywords used in the search engine were: endurance athlete, diet, oxidative stress, physical activity, diet, nutrition, antioxidant, antioxidant status, vitamin C, vitamin A, vitamin E, β-carotene and combinations. Twelve studies were identified and organized according to the methodology and results of supplementation: ergogenic, ergolytic, partial or no difference between groups. The results of these studies showed no effect on physiological parameters and activity of antioxidant enzymes (n = 07), better response of the placebo treatment (ergolytic effect; n = 02), partial results (n = 01) and ergogenic results of antioxidant supplementation (n = 02). It is concluded that supplementation with antioxidant vitamins has controversial effects to oxidative damage induced by endurance exercise. The discordances among the studies are presented and discussed.

Effects of tadalafil administration on plasma markers of exercise-induced muscle damage, IL6 and antioxidant status capacity

“…Tadalafil, because of its longest half-life with respect to the other PDE5i, has been considered an ideal candidate as a possible performance enhancer and antioxidant drug, but our results indicate that doses and duration of tadalafil administration should be carefully evaluated. It is noteworthy that other molecules involved in antioxidant defense such as polyphenols or vitamins show an antioxidant or a pro-oxidant effect depending on the doses and length of supplementation (Ndahala et al 2010;Draeger et al 2014;Myburgh 2014). Moreover, when analyzing a molecule as a potential antioxidant, it is necessary to consider also the potential impact of different lifestyles on exercise-induced stress-oxidative response.…”

Dietary Antioxidants as Modifiers of Physiologic Adaptations to Exercise

“…This concern has led some experts to suggest consuming more dietary AOs and AO-containing supplements to mitigate the ROS production that can cause excess oxidative stress during and after exercise (9, 36, 47, 65). This belief that dietary supplements are helpful, or at least safe, when used in conjunction with an exercise program, however, has recently been questioned.…”

A genetic-based algorithm for recovery: A pilot study

“…Other interventions that may enhance recovery include cold water immersion (CWI) and the use of compression garments, although the results are currently equivocal (Leeder et al, 2011;Bleakley & Davison, 2009;Ascensao et al, 2010;Jakeman et al, 2009;Duffield et al, 2010;Duffield et al, 2008;Jakesment et al, 2010). It should be noted that exercise adaptation relies on the application of stress to the body, and the use of antioxidant supplements and CWI may blunt this adaptation (Draeger et al, 2014;Yamane et al, 2015), or in some cases reduce speed of recovery (Close et al, 2006).…”