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:

Here is a quick roundup of some of the most popular supplemental ergogenic aids

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

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.