CORDYCEPS IS A FUNGUS THAT GROWS on Tibetan caterpillars. Practitioners of traditional Chinese medicine (TCM) have used it to treat fatigue and other ailments for 1,500 years. After the 1992 Olympics, Chinese athletes attributed their wins to their use of the fungus, which sparked American interest in cordyceps. Most Western manufacturers grow it without caterpillars.
How It Works
Researchers don't know exactly how cordyceps boosts energy and endurance. They theorize that it may help your body use energy more efficiently by increasing blood flow to your liver and other organs and by improving your oxygen use. Cordyceps's antioxidant activity may alleviate fatigue.
Evidence
Recent research on cordyceps is limited. The few studies conducted were sponsored by supplement manufacturers, and the results are modest.
One double-blind study, published in the American Journal of Clinical Nutrition in February, tested the energy and endurance of 110 healthy sedentary adults. In it, half took 3 g of cordyceps daily while the other half took a placebo. After 12 weeks, the cordyceps group could bicycle 2.8 percent longer than they could before taking the supplement, while the placebo group decreased the length of their rides by 5.6 percent.
In a double-blind study published in Medicine & Science in Sports & Exercise last year, researchers gave 30 male athletes either 4.5 g of cordyceps daily or a placebo. The athletes did not change their exercise routine during the study. After six weeks, the cordyceps group's oxygen intake was almost double the placebo group's. This increased oxygen intake helped their bodies work more efficiently.
In another study published in the same journal in 1999, 30 healthy elderly Chinese people took either 3 g of cordyceps daily or a placebo. After six weeks, aerobic capacity in the cordyceps group increased 9 percent, which researchers say produced higher energy levels, while those taking the placebo saw no energy change.
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Extract from the article "Boost energy with cordyceps: this Chinese fungus helps athletes go further " by Rich Gravelin, August 2002, Natural Health