Sports nutrition caffeine

Clarkson, P. M., Nutritional ergogenic aids Caffeine, International Journal of Sport Nutrition, 3, 103, 1993. 

This is a controversial central nervous system stimulant. The source is the dried leaves of a Chinese plant. It is used in sports nutrition and diet products. It contains ephidrene, an alkaloid found in decongestants and asthma medicine. Death has resulted for some people who took it and had heart, thyroid, circulatory problems, or, in some instances, combined it with caffeine. In many states pharmacists only sell it to people 18 or older. 

Armstrong LE (2002) Caffeine, body fluid-electrolyte balance and exercise performance. International Journal of Sport Nutrition and Exercise Metabolism 12 205-222. 

Tarnopolsky, M.A., Gibala, M., Jeukendrup, A.E., and Phillips, S.M., Nutritional needs of elite endurance athletes. Part II. Dietary protein and the potential role of caffeine and creatine, Eur. J. Sport Sci., 5, 59-72, 2005. 

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