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Ephedra and its application to sport performance: another concern for the athletic trainer?
1University of Florida, Gainesville, FL.
Objective:
The ma huang herb, otherwise known as ephedra, has gained widespread popularity as an ergogenic supplement. With the sympathomimetic alkaloid ephedrine as its primary active ingredient, ma huang is marketed to reduce fatigue; increase strength, power, and speed; decrease reaction time; and improve body composition. Although numerous side effects have been associated with the use of ma huang, its popularity in athletes continues to grow. This review provides rationale for the ergogenic claims regarding ma huang and compares and contrasts those claims with data from scientifically controlled investigations.
Data Sources:
MEDLINE and SPORT Discus were searched from 1970 to 2000 using the key words ma huang, ephedra, and ephedrine in combination with humans, exercise, performance, and side effects.
Data Synthesis:
Ephedrine has been used alone or in combination with other drugs as an effective weight-loss agent. The weight loss has been attributed to thermogenic and lipolytic effects which, in combination with the central nervous system stimulating effects, have also resulted in its use as an ergogenic aid. Most of the scientific data, however, do not support manufacturers' ergogenic claims, and numerous side effects have been associated with ephedrine use. Thus, the safety and efficacy of ma huang as an ergogenic supplement must be questioned.
Conclusions/Recommendations:
It appears that the risks associated with the use of ma huang far outweigh any possible ergogenic benefits. Thus, it is extremely important that athletic trainers educate athletes on these issues so they can continue to perform at an optimum level in a safe and healthy manner.
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