Antioxidants – Why they are important in exercise and body building
Antioxidants are molecules that reduce or inhibit cell damage by free radicals thereby preventing oxidative stress and potentially delaying aging [ii]. Free radicals are unstable molecules that can cause cellular damage. They are produced naturally in our body every day as part of our normal metabolism and also result from external factors including pollution, pesticides, chemicals and radiation[ii].
Strenuous exercise can cause oxidative stress as a result of this elevated ROS overwhelming our tissue antioxidant defence systems. The degree of the stress depends upon the antioxidant defences ability to detoxify the ROS. Furthermore mounting evidence implements the ROS produced as a contributor to muscle fatigue and protein oxidation[iii].
There are two major classes of endogenous protective mechanisms, the enzymatic and non-enzymatic antioxidants, these work to reduce the harmful effects of reactive oxygen species in cells[ii]. Furthermore, dietary antioxidants interact with endogenous antioxidants to form a cooperative antioxidant network.
Research surrounding the use of antioxidants for exercise ROS is still inconclusive, giving mixed results. Below are just a few of the research papers available.
Sen (2001) states an that antioxidant diet and supplementation is highly recommended[iv]. This was also the case in Hellsten et als (2007) study where the researchers concluded that antioxidant supplementation enhanced exercise-induced adaptive responses of certain proteins[v]. However there is also conflicting research showing that isolated nutrient supplementation was ineffective in regards to exercise performance[ii].
Research by Dphilla et al (2002) demonstrated that consuming a diet rich in antioxidants resulted in increased blood levels of antioxidants[vi], this could form the impetus of further research into foods as an antioxidant inclusion in exercise regimes rather than isolated nutrient supplementation.
It could be postulated based on these results that consuming a diet rich in antioxidants may beneficially affect the exercising individual. Furthermore consuming antioxidant foods in their whole form are nutritious, safe and the synergistic effects are indisputable.
[i] Leeuwenburgh C and Heinecke J.W (2001) Oxidative Stress and Antioxidants in Exercise. Current Medicinal Chemistry; 8: 829-838.
[ii] Devasagayam T.P.A, et al (2004) Free Radicals and Antioxidants in Human Health: Current Status and Future Prospects. JAPI;52:794-804.
[iii] Powers S.K, Deruisseau K.C, John Quindry J & Hamilton K.L (2004) Dietary antioxidants and exercise. J of Sports Sci;22:81–94.
[iv] Sen, C.K (2001) Antioxidants in Exercise Nutrition. Sports Med;31(13):891-908.
[v] Hellstena Y, Nielsen J.J, et al (2007) Antioxidant supplementation enhances the exercise-induced increase in mitochondrial uncoupling protein 3 and endothelial nitric oxide synthase mRNA content in human skeletal muscle. Free Radical Bio and Med;43(3):353–361.
[vi] DPhilla J.H, Ziebland S, et al (2002) Effects of fruit and vegetable consumption on plasma antioxidant concentrations and blood pressure: a randomised controlled trial; 359(9322):1969–1974.