Additional vitamins taken to make up a deficit, to avoid a vitamin deficiency disease, or to enhance athletic performance. There is much controversy concerning the value of vitamin supplements as ergogenic aids. There is little evidence to support the notion that extra vitamins improve the physical performance of athletes already eating a balanced diet and not suffering from a vitamin deficiency. However, high doses of vitamins may improve athletic performance by acting as drugs in, as yet, undefined ways. Also, athletes in hard training are generally advised to take care that they have a sufficient intake of antioxidant vitamins to counteract the harmful effects of free radicals produced as a result of the high energy turnover of active skeletal muscle (this can be up to 100 times the resting rate). Taking supplements of fat-soluble vitamins can be dangerous because they can be stored in adipose tissue and may be toxic in high concentrations. See also sports nutrition.
Subjects: Sports and Exercise Medicine.