Ergogenic aid	Action	Research on ergogenic effects	Side effects	Legality
Alcohol	Decreases anxiety	No benefits	Significant	Banned for shooting events
Amphetamines	Improve concentration, decrease fatigue and appetite	Mixed, some positive	Significant, dangerous	Illegal
Anabolic steroids	Increase strength, lean muscle mass and motivation	Positive	Significant, dangerous	Illegal
Androstenediol	Same as steroids	Limited, refutes	Unknown	Banned by IOC
Androstenedione	Same as steroids	Refutes, no benefits	Significant	Banned by IOC, NCAA
Antioxidants	Decrease muscle breakdown	Mixed, no clear benefits	Mild at high doses	Legal
Arginine, ornithine, lysine	Stimulate growth hormone release	No benefit	None at doses used	Legal
Aspartates	Increase free fatty acid use, sparing muscle glycogen	Mixed, some positive benefits	Mild at high doses	Legal
Aspirin	Decreases pain with muscle fatigue and muscle breakdown	No benefit	Mild	Legal
Avena sativa	Increases steroid production	Limited, refutes	None	Legal
Bee pollen	Increases strength and endurance	Refutes, no benefits	Allergic reaction	Legal
Beta blockers	Decrease anxiety	Positive effect on fine motor control, negative effect on aerobic capacity	Significant	Banned by IOC
Beta2 agonists	Increase lean muscle mass	Mixed, no benefit from inhaled formulations	Mild	Banned by IOC, legal when prescribed
Blood doping	Increases aerobic capacity	Supports	Significant, dangerous	Illegal
Boron	Increases endogenous steroid production	Refutes, no benefit	Mild at high doses	Legal
Branched chain amino acids	Decrease mental fatigue	Mixed, negative	Mild at high doses	Legal
Caffeine	Increases muscle contractility and aerobic endurance, enhances fat metabolism	Supports	Mild	Legal to urine level of 12 to 15 μg per mL
Calcium	Increases muscle contractility, enhances glycogen metabolism	Refutes, no benefit	Mild at high doses	Legal
Carbohydrates	Increase endurance, decrease fatigue	Supports	Mild at high doses	Legal
Carnitine	Increases fat metabolism	Refutes	None	Legal
Choline	Increases endurance	Mixed, inconclusive	None	Legal
Chromium	Increases lean mass	Refutes, no benefit unless prior deficiency	Safe to 400 μg daily, potentially dangerous above this level	Legal
Chrysin	Inhibits aromatase, increases endogenous steroids	Limited, refutes	None	Legal
Cocaine	Stimulates CNS, delays fatigue	Mixed	Significant, dangerous	Illegal
Coenzyme Q10 (ubiquinone)	Delays fatigue, acts as antioxidant	Refutes, no benefit	None	Legal
Coenzyme Q12	Increases aerobic capacity, speeds muscle repair	Refutes, no benefit	None	Legal
Creatine	Increases muscle energy, endurance, strength and lean muscle mass	Supports, insufficient data on long-term use	Mild	Legal
DHEA	Increases endogenous steroid production	No benefit in healthy athletes	Potentially dangerous	Banned by IOC, some other organizations
Diuretics	Decrease body mass	Limited benefit	Potentially dangerous	Banned by IOC
Ephedrine, other sympathomimetics	Stimulate CNS, increase energy, delay fatigue, stimulate weight loss	No benefit	Potentially dangerous	Banned by IOC, some other organizations
Ephedrine plus caffeine	Increases energy, stimulates weight loss	Supports	Potentially dangerous, fatal at high doses	Banned by IOC, some other organizations
Erythropoietin	Increases aerobic capacity	Supports	Significant, dangerous	Illegal
Fat supplements	Increase endurance	Refutes	Mild	Legal
Fluids	Increase endurance	Supports	Mild	Legal
Folic acid	Increases aerobic capacity	Refutes	None	Legal
GHB	Stimulates growth hormone release and muscle growth	Limited, refutes	Significant, dose-related; abuse potential	Illegal
Ginseng	Increases endurance, enhances muscle recovery	Limited, refutes, no benefit	Mild, abuse syndrome reported	Legal
Glucosamine	Serves as NSAID alternative, enhances recovery	Limited, may have limited NSAID abilities	None	Legal
Glutamine	Boosts immunity and growth hormone levels	May boost immunity, no other benefits	None	Legal
Glycerol	Improves hydration and endurance	Limited, supports	Mild	Legal (oral)
Guarana (herbal caffeine)	Same as caffeine
HMB	Decreases muscle breakdown, enhances recovery	Limited, some strength benefits	None	Legal
Human growth hormone	Anabolic effect on muscle growth, increases fat metabolism	Refutes, limited ergogenic benefits	Significant, dangerous	Illegal
Inosine	Enhances energy production, improves aerobic capacity	Refutes, no benefit	Mild	Legal
Iron	Increases aerobic capacity	No benefit unless preexisting deficiency	Mild, toxic at high doses	Legal
Leucine	Decreases muscle breakdown and spare muscle glycogen stores	Limited, no ergogenic effect	None	Legal
Ma huang (herbal ephedrine)	Same as ephedrine
Magnesium	Enhances muscle growth	No benefit unless preexisting deficiency	Mild at high doses	Legal
Marijuana	Decreases anxiety	Refutes, negative effect	Significant, dangerous	Illegal
Multivitamins	Increases energy, endurance and aerobic capacity, enhances recovery	No benefit unless preexisting deficiency	None at RDA, some toxicities at high doses	Legal
Narcotics	Increase endurance by suppressing pain, decrease anxiety	Mixed, negative	Significant, dangerous	Illegal
Niacin	Increases energy and endurance	No benefit unless a preexisting deficiency	Mild at high doses	Legal
Oxygen	Increases aerobic capacity, enhances recovery	No benefit if given before or after activity	Mild	Legal
Phosphates	Increase ATP production, energy and muscle endurance	Mixed, negative	Mild at high doses	Legal
Phytosterols	Stimulates release of endogenous steroids and growth hormone	Refutes, no benefit	Little data, allergic reaction possible	Legal
Protein	Optimizes muscular growth and repair	Supports, increased need for protein with activity	None unless underlying medical condition	Legal
Pycnogenol	Boosts antioxidant levels, enhances recovery	Supports, dietary sources offer same benefit	None	Legal
Pyruvate	Increases lean body mass	Limited research, benefit only in specific cases	None	Legal
D-Ribose	Increases cellular ATP and muscle power	No human research	None known	Legal
Selenium	Enhances antioxidant functions	Limited, no benefit	Mild at high doses	Legal
Sodium bicarbonate	Buffers lactic acid production, delays fatigue	Supports	Mild, dangerous at high doses	Legal
Strychnine	Unknown	No research on ergogenic benefits	Significant, dangerous	Legal
Tribulus terrestris	Increases endogenous steroid production	Refutes	Potentially dangerous at high doses	Legal
Tryptophan	Decreases pain perception, increases endurance	Mixed, no benefit in trained athletes	Mild, potentially dangerous	Legal
Vanadyl sulfate	Increases glycogen synthesis, enhances muscle recovery	Refutes, no benefit in healthy individuals	Mild	Legal
Vitamin B1 (thiamin)	Enhances energy production, increases aerobic capacity, improves concentration	No benefit unless preexisting deficiency	None	Legal
Vitamin B2 (riboflavin)	Increases aerobic endurance	No benefit unless preexisting deficiency	None	Legal
Vitamin B6 (pyridoxine)	Enhances muscle growth, decreases anxiety	No benefit unless preexisting deficiency	Mild at high doses	Legal
Vitamin B12 (cyanocobalamin)	Enhances muscle growth	No benefit unless preexisting deficiency	None	Legal
Vitamin B15 (dimethylglycine)	Increases muscle energy production	Mixed, negative	None proven, but concerns raised	Legal
Vitamin C	Acts as antioxidant, increases aerobic capacity and energy production	No benefit unless preexisting deficiency	Mild at high doses	Legal
Vitamin E	Acts as antioxidant, improves aerobic capacity	Mixed, some positive	Mild	Legal
Yohimbine	Increases endogenous steroid production	Refutes, no benefit	Mild	Legal
Zinc	Enhances muscle growth, increases aerobic capacity	Limited, negative	Mild	Legal