ANTIOXIDANTS, CARNITINE, AND CHOLINE AS PUTATIVE ERGOGENIC AIDS

Three nutritional products that have very different mechanisms of acti on are antioxidant vitamins, carnitine, and choline. Antioxidant vitam ins do not appear to have a direct effect on physical performance in w ell-fed people but have been touted for their ability to detoxify pote ntially damaging free radicals produced during exercise. Carnitine pur portedly enhances lipid oxidation, increases VO(2)max, and decreases p lasma lactate accumulation during exercise. However, studies of carnit ine do not generally support its use for ergogenic purposes. Choline s upplements have been advocated as a means of preventing the decline in acetylcholine production purported to occur during exercise; this dec line may reduce the transmission of contraction-generating impulses ac ross the skeletal muscle, an effect that could impair one's ability to perform muscular work. However, there are no definitive studies in hu mans that justify choline supplementation. Much of the scientific data regarding the aforementioned nutrients are equivocal and contradictor y. Their potential efficacy for improving physical performance remains largely theoretical.