Page Love, MS, RD, LD
From herbs to creatine to chromium, have you been tempted to try a magic bullet to improve your athletic performance? Many supplements are touted as quick energy boosters, fat burners or muscle builders. Do these pills and powders really work? According to Dr. Melvin Williams, a physiology expert on sport nutrition supplements, “Most dietary supplements have not been adequately researched to support their efficacy.” For example, some research suggests that active people may need more protein than inactive people; but because the average American eats two times the Recommended Dietary Allowance for protein, protein powders or amino acid pills are unnecessary, not to mention the expense - costing athletes up to $200/month. In fact, in some cases taking high doses of some of these sport supplements may have a more negative than positive effect on performance. For example, when some herbs are used as ergogenic aids, athletes may be at risk for dehydration, stomach upset and muscle tremors.
Be aware that advertising may be deceptive and may lead the athlete astray. Currently, supplement manufacturers put many unproven claims on their packaging. Even when a supplement manufacturer claims to have research to support the claims on their supplements, often the research has not been published in a refereed scientific journal (i.e. The New England Journal of Medicine or The Journal of the American Medical Association) and the research may be conducted by the manufacturer in their own labs. Often supplements are promoted by paid advertisements and personal testimonials. Safety of many products is also an issue. Unfortunately, in the U.S. the Dietary Supplement Health and Education Act puts the burden of proving product safety on the FDA which means, until negative side effects are reported, the FDA will not investigate the safety and efficacy of a particular supplement. In order to prove a supplement’s efficacy, more well randomized, placebo controlled, double blind studies are needed.
At a recent workshop on “The Role of Dietary Supplements for Physically Active People: held at the National Institutes of Health," the scientific research was reviewed on many popular supplements. Of the supplements presented, the nutrients of most promise to enhance performance were Vitamin E and creatine. Vitamin E, an antioxidant, may help with reducing free radical damage after exercising, thus possibly speeding up recovery time after heavy training periods or tournament play. However, research in this area is not conclusive. The current recommendation is to eat a diet rich in fruits and vegetables. But to receive adequate Vitamin E, athletes must consume whole grains and small amounts of seed oils; thus, there is a need for small amounts of oil in salad dressings or in cooking, in peanut butter or margarine, etc. Taking a multivitamin that contains up to 400 IU of vitamin E is also considered safe.
With creatine, a supplement purported to increase muscle strength, size and improve anaerobic performance, current research is promising. Creatine, a natural compound found in muscle tissue manufactured as a metabolite of animal protein consumption is crucial for high intensity short duration power output. When taken in supplement form to supersaturate the muscle, a dosage of 20 gms for 5 days (the amount of creatine the body would produce after consumption of the equivalent to 9 lbs. of meat) has caused increases in maximum strength and quicker recovery time from intense muscle fatigue. Research in this area has not been sport specific to date and there are some side effect concerns. An increase in water is needed when taking the creatine supplement because of the increased use of water in utilizing the compound, as it holds more water in the muscle fibers. Side effects reported to date are players while playing in the heat. According to Dr. Michael Bergeron, a physiology expert on hydration issues, “Drinking up to an extra quart of water per day may be needed when taking creatine to limit the occurrence of the problems." (This brings the total fluid intake for the tennis player to 4 quarts or 1 gallon per day). Other long-term side effects with creatine supplementation are not known at the present time. And, with most fad nutritional supplements, time will tell about their long-term safety and efficacy, so sit tight and proceed with caution.