Jury’s Still Out on Whether Ginseng Is an Exercise Aid

Ginseng has been touted as a remedy for fatigue, a reviver of sexual appetite and a booster of athletic performance. A recent evaluation of the last claim found no effect from the popular herbal supplement.

Researchers at Wayne State University in Detroit measured signs of exertion (oxygen consumption, blood lactic-acid concentration, heart rate and others) in 31 healthy men while they worked at maximum effort on stationary cycles. The men were then divided into three groups. For eight weeks, one group took 200 milligrams a day of Panax, a ginseng concentrate made by C.A. Meyer” (also called Chinese or Korean ginseng), another took 400 milligrams a day, and the third group took an identical-looking placebo. They agreed to maintain their usual diet and activity patterns during this time. Neither the men nor the researchers knew who was assigned to which group until the end of the trial.

When the men were retested after eight weeks, supplementation “was found to have no effect on any of the physiologic and psychological parameters examined,” wrote researchers Hermann-J. Engels and John C. Wirth in their report in the Journal of the American Dietetic Assn. Some earlier studies, though not all, had found a benefit from ginseng in exercise. While Engels and Wirth faulted these studies generally for “methodologic and statistical inadequacies,” they concluded that further investigations are needed to evaluate ginseng’s efficacy and safety.