Ergogenic Aids: Nutritional Supplements for Athletes
What are they?
Ergogenic aids are substances, devices, or practices that enhance an individual’s energy use, production, or recovery. The form an ergogenic aid may take can be quite varied. Stretching and weight training are physical ergogenic aids. Visualization and hypnosis are mental ergogenic aids. Lighter weight running shoes and better designed golf clubs are mechanical ergogenic aids. But perhaps the most commonly recognized form of ergogenic aids is the dietary supplement.
Who uses them?
The availability and use of supplements as ergogenic aids have risen dramatically in the past decade. Some surveys have indicated that approximately 50% of the general population, 76% of college athletes, and 100% of bodybuilders take supplements. New products appear on the market every week.
Are they safe?
Being labeled as a “supplement” means that the contents of the product and the claims put forth on the label have not been evaluated by the US Food and Drug Administration. The FDA inspects food and drug products to insure safety and truthful content before they can be marketed to the public. Anything labeled as a “supplement” can be marketed as such without prior FDA approval as provided for under the Dietary Supplement and Health Education Act of 1994. This should be a concern for anyone thinking about taking dietary supplements, as the burden of evaluating any claims made on the label by a manufacturer now falls on the consumer. Many such claims include a statement either that the FDA has not evaluated the claim or that the product is not intended to “diagnose, treat, cure or prevent any disease” (a type of claim that can only legally be made by a drug).
What can I do?
If you decide to take a supplement, there are many ways to go about evaluating its safety and efficacy:
- Look for supplements with the U.S. Pharmacopoeia (USP) or National Formulary (NF) notation. These mean the manufacturer has undergone voluntary evaluation of product purity, strength, labeling and weight variation.
- Ask a health care professional who is knowledgeable about nutrition and supplements.
- Do a literature search, being wary of articles or publications funded by the manufacturer of the supplement.
- Determine the reputability of the manufacturer. Have they been in business for a long time? Do they have quality control standards? Do they publish their own research? Is their research cited in peer-reviewed journals?
- Note any side effects associated with the supplement.
- Is the proposed benefit worth the cost or risk?
- Are there any illegal or banned substances contained within the supplement?
- Will the supplement interfere with or otherwise affect any medications or other supplements you may be taking?
| Supplement | Claimed Action | Research on Action | Side Effects | Legality |
|---|---|---|---|---|
amphetamines |
improve concentration, decreases fatigue and appetite |
supports |
significant, dangerous |
banned for shooting events |
anabolic steroids |
increases strength, lean muscle mass, and motivation |
supports |
significant, dangerous |
illegal |
androstenediol |
same as steroids |
limited, refutes |
unknown |
banned by Olympics |
androstenedione |
same as steroids |
refutes, no benefits |
significant |
banned by Olympics and NCAA |
beta-hydroxy-beta-methyl butyrate (HMB) |
Prevents breakdown and enhances synthesis of protein, increases strength, improves body composition |
supports |
long term effects unknown |
legal |
blood doping |
increases aerobic capacity |
supports |
significant, dangerous |
illegal |
branched chain amino acids (BCAA) |
enhance endurance performance, anti-catabolic (slows down muscle breakdown) |
mixed, some support for anit-catabolic function |
appears safe |
legal |
caffeine |
increases muscle contractility and aerobic endurance, enhances fat metabolism |
supports |
mild |
legal to certain urine levels |
carnitine |
increases fat metabolism |
refutes, no benefits |
none |
legal |
chromium |
increase lean mass |
refutes, no benefit unless prior deficiency |
safe to 400 mg daily, potentially dangerous above this level |
legal |
coenzyme Q10 |
enhances function of electron transport chain, improves endurance performance |
does not support use for athletes |
appears safe |
legal |
conjugated linoleic acid (CLA) |
increases response to tissue growth factors, hormones, and cell messengers, increases muscle mass, weight loss, and fat loss |
limited, animal studies |
GI distress |
legal |
creatine monohydrate |
increases muscle energy, short term endurance, strength, and lean muscle mass |
supports, insufficient data on long-term use |
mild |
legal |
dehydroepiandrosterone (DHEA) |
increases endogenous steroid production |
no benefit in healthy athlete |
potentially dangerous |
banned by Olympics |
energy gels |
quickly supply carbohydrates during endurance exercise |
supports |
none, if taken with water |
legal |
ephedrine |
stimulates CNS, increases energy, delays fatigue, stimulates weight loss |
no benefit |
potentially dangerous |
banned by Olympics, FDA and other organizations |
fluids |
increases endurance |
supports |
mild |
legal |
human growth hormone |
increases muscle mass, strength and power, decrease fat mass |
supports |
causes enlargement of organs and increases risk of chronic disease |
banned by world anti-doping agency |
leucine |
decreases muscle breakdown, spares muscle glycogen stores |
limited, no ergogenic effect |
none |
legal |
medium chain triglycerides (MCT) |
increases energy and muscle cell mass, decrease fat mass, delay fatigue |
limited |
intestinal cramping and diarrhea |
legal |
multivitamins |
increases energy, endurance and aerobic capacity, enhance recovery |
no benefit unless preexisting deficiency |
none at RDA, some toxicities at high doses |
legal |
phosphates |
increases ATP production, energy and muscle endurance |
limited support |
mild at high doses |
legal |
protein |
optimizes muscular growth and repair |
supports, increased need for protein with activity |
none unless underlying medical condition |
legal |
sports drinks |
increases endurance performance, supply fluid, carbohydrate, and electrolytes |
supports |
none |
legal |
zinc |
increases physical endurance, mental alertness, concentration, free testosterone |
limited |
none if taken in recommended dosages |
legal |
Creatine is an amino acid in the skeletal muscle, as well as the liver, pancreas, and kidneys. Supplemental creatine is a popular ergogenic aid, but its benefits are limited. Research has shown creatine to be effective in increasing muscle strength and power during brief, high intensity exercise lasting about one minute or less (such as sprinting and weight lifting). It is believed to work by improving ATP metabolism. Creatine will not benefit endurance athletes. A common side effect is weight gain, which can make athletes feel sluggish. Other reported side effects include diarrhea, muscle cramps, and dehydration. For the most part, however, creatine is considered safe when taken in recommended dosages. Athletes often take creatine in phases. During the loading phase, athletes consume 20-25 grams (in 5 gram increments) per day for 4-7 days. During the maintenance phase, 2-5 grams per day are consumed. Creatine can be obtained through animal foods, such as meat and fish, but in amounts less than 2 grams. Creatine may be slightly more effective when combined with glucose; thus it is frequently sold in combination with carbohydrate. Individual responsiveness to creatine may vary. Vegetarians, who may consume little creatine in the diet, may experience a more pronounced response to creatine supplementation than non-vegetarians.
For more information
- American Council for Science and Health Web site, search for the topic or click on the nutrition/lifestyle link
- The Physician and Sportsmedicine Web site, search for nutrition/lifestyle
- Gatorade Sports Science Institute Web site, search for nutrition/lifestyle
- Consumer Lab Web site, search for nutrition/lifestyle
References
USDA Food Surveys Research Group. Supplementary data tables USDA’s 1994-1996 continuing survey of food intakes by individuals. 1999; Table set 12:33.Sobal J, Marquart LF. Vitamin/mineral supplement use among athletes: a review of the literature. Int. J Sports Nutr. 1994; 4:320-34.
US Food and Drug Administration Web site, search for dietary supplements
Streich, Cynthia MS. Nutritional Ergogenic Aids.
University of Wisconsin Hospital and Clinic Web site
Ahrendt, Dale M, MD. Ergogenic Aids: Counseling the Athlete. American Family Physician 2001; v 63:913-22.
Supplement Watch Web site
Cioca, M. (2005). “Medication and Supplement Use by Athletes.” Clinical Sports Med 24, 719-738.
Fink HH, Burgoon LA, Mikesky AE. Practical Applications in Sports Nutrition. Sudbury, MA: Jones and Bartlett Publishers, 2006.
Dhar R. et al. Cardiovascular toxicities of performance-enhancing substances in sports. Mayo Clinic Proceedings. 2005;80(10):1307-1315.
Applegate, Liz. Eat Smart, Play Hard. Rodale, 2001.
Kundrat, Susan. 101 Sports Nutrition Tips. Coaches Choice, 2005.