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There’s such a dizzying array of sports nutrition supplements available on the Internet and in your local health-food store that figuring out where to start can feel overwhelming. You probably suspect some are more beneficial than others, but which ones are worth the money?

The sad truth is, most supplements don’t live up to their marketing hype. And no supplement can replace a sensible diet or hard training. But a handful of these products do provide real, scientifically proven benefits for athletes, such as faster post-exercise recovery, enhanced workout performance and reduced risk of injury. Here, we’ll identify those supplements and explain how they work, as well as suggest who should consider using them and explain how to use them properly — though, as with any diet or exercise overhaul, you should first consult with your physician.


  • What it is: A multivitamin is a pill containing most or all of the 13 essential vitamins and 22 essential minerals.
  • What it does: “Multivitamins provide insurance against the performance consequences of vitamin and mineral deficiencies, which are common even among athletes,” says Robert Portman, PhD, author of Nutrient Timing. Many athletes suffer from fatigue caused by iron deficiency anemia, for example, which a good multivitamin-multimineral supplement may help prevent.
  • The science: A 2007 study published in the Journal of the American College of Nutrition found that 14 days of multivitamin supplementation reduced exercise-induced cell damage in athletes
  • How to use it: Follow label directions.

Glucosamine, Chondroitin and Methyl Sulfonyl Methane (MSM)

  • What it is: Glucosamine and chondroitin are constituents of joint cartilage. MSM is a natural pain reliever.
  • What it does: “Glucosamine, chondroitin and MSM may lessen joint damage and treat joint pain resulting from training,” says Jose Antonio, PhD, CEO of the International Society of Sports Nutrition.
  • The scientific case for it: A large, three-year NIH study from 2000 to 2002 found that a combination of glucosamine and chondroitin reduced joint pain in patients suffering from moderate to severe cases of knee osteoarthritis. And a 2004 clinical study found glucosamine and MSM to effectively reduce pain and inflammation in patients suffering from osteoarthritis.
  • How to use it: Typical doses are 1,500 mg glucosamine and 500 mg chondroitin and 2 to 4 grams of MSM per day.

Fish Oil

  • What it is: Fish oil supplements are rich in the essential omega-3 fatty acids EPA and DHA, which are scarce in the average person’s diet.
  • What it does: According to Antonio, fish oil supplements increase insulin sensitivity, which helps the muscles draw glucose from the cells faster during exercise. They also have anti-inflammatory properties, which may help to speed post-exercise muscle recovery.
  • The scientific case for it: In a 2008 study, researchers at the University of Surrey, England, found that 60 days of fish oil supplementation increased insulin sensitivity in overweight subjects.
  • How to use it: Antonio recommends a daily dosage of 2 to 3 g of EPA and DHA (combined) daily. Be sure you buy a brand that’s at least 50 percent pure. (You can calculate the percentage by dividing the amount of combined EPA and DHA by the total amount of fat in the product.)

For more, see “Fish Oil: Health Benefits of Supplementing for Your Body and Brain“.

Green Tea

  • What it is: Green tea is an antioxidant-rich beverage made from the leaves of the Chinese plant camellia sinsensis.
  • What it does: “Green tea offers a host of health benefits including improved blood sugar, fat loss, improved circulation and cancer prevention,” says Ryan Andrews, RD, director of education for Toronto-based Precision Nutrition (
  • The scientific case for it: Animal studies have found that supplementation with green tea extracts improves exercise endurance by increasing the muscles’ fat-burning capacity. And in a 2008 human study from the University of Birmingham, England, acute supplementation with green tea extract increased fat burning during moderate-intensity exercise by 17 percent.
  • How to use it: Drink one to three cups of green tea per day.

Learn more about the health benefits of tea at “What Are the Health Benefits of Drinking Tea?“.


  • What it is: Coenzyme Q10 (CoQ10) is a compound that is present in every cell of the body and plays a vital role in energy release.
  • What it does: According to Adam Russell, PhD, a human-performance expert who consults with the U.S. national rugby team, long-term CoQ10 supplementation may help athletes to recover more quickly after high-intensity workouts.
  • The scientific case for it: A 2008 study published in the Journal of the International Society of Sports Nutrition reported that 14 days of CoQ10 increased trained athletes’ time to exhaustion in an endurance exercise test. “The science is far from a slam dunk, however,” notes Russell.
  • How to use it: Russell recommends taking 150 to 200 mg per day, and notes that CoQ10 comes in two main forms: ubiquinone and ubiquinol. “The ubiquinol form of CoQ10 is the most bioavailable,” says Russell, meaning the body uses it more effectively, so look for “ubiquinol” on the product label.

Go deeper at “CoQ10: The Miracle Molecule“.

Green Foods Antioxidant Supplement

  • What it is: “Greens supplements are basically veggies and fruits that have been compacted and distilled into powdered form,” says Andrews.
  • What it does: Green-foods supplements are rich in antioxidants, which neutralize free radicals produced during exercise, thereby reducing muscle fatigue and post-exercise muscle soreness. They also have an alkalinizing effect on the body — meaning they make it less acidic — which promotes muscle mass maintenance.
  • The scientific case for it: A 2008 study published recently in the Journal of the International Society of Sports Nutrition reported that seven days of supplementation with a green-foods antioxidant supplement increased urinary pH (indicative of reduced body acidity) in a population of active men and women.
  • How to use it: Follow the directions on the label.

Check out “SuperGreens” to learn how to get more greens in your diet and what they can do for you.

Amino Acid Mix

  • What it is: Amino acids are the nutrient building blocks of proteins. There are various amino acid supplements on the market, but Antonio recommends those that contain all eight essential amino acids (phenylalanine, valine, threonine, tryptophan, isoleucine, methionine, leucine and lysine).
  • What it does: Taking an amino acid supplement either right before or right after workouts accelerates muscle tissue repair, Antonio says. And it increases the muscle mass gains resulting from resistance workouts.
  • The scientific case for it: A 2006 study by researchers at Baylor University in Texas found that amino acid supplementation before and after exercise increased muscle gains resulting from a 10-week resistance-training program.
  • How to use it: “Take 3 to 6 grams of amino acids immediately prior to or after exercise,” says Antonio. “Three grams will do if you weigh less than 120 pounds; 6 if you’re more than 200.”

Creatine Monohydrate

  • What it is: Creatine monohydrate is a nutrient precursor of creatine phosphate, an important source of energy for maximum-intensity muscle work.
  • What it does: “Creatine supplementation, when combined with appropriate training, is proven to increase lean body mass, muscle power, strength and repeated sprint performance,” says Antonio. It also reduces recovery time, allowing you to work out more rigorously, more often.
  • The scientific case for it: The case for creatine is well documented. A 1999 Penn State study, for instance, found that creatine supplementation more than doubled the gains in lean body mass resulting from 12 weeks of resistance training.
  • How to use it: Take 3 to 5 grams per day. Results may be seen in as little as one week.


  • What it is: Beta-alanine is an amino acid constituent of carnosine, a compound that buffers acids produced by the muscles during very high-intensity exercise.
  • What it does: Acid production is a major cause of muscle fatigue during high-intensity exercise, Antonio explains. “Beta-alanine supplementation improves acid buffering, thereby enhancing anaerobic endurance.”
  • The scientific case for it: A 2007 Belgian study found that four weeks of beta-alanine supplementation improved performance when compared with four weeks of placebo doses in a test of anaerobic exercise capacity.
  • How to use it: Antonio recommends a dosage of 3 to 6 grams of beta-alanine daily. Results may be seen in two to three weeks.


  • What it is: Zinc and magnesium are essential minerals.
  • What it does: Zinc and magnesium supplements are mainly marketed as testosterone boosters and muscle builders, but Russell believes they are much better used to boost the immune systems of athletes in heavy training.
  • The scientific case for it: A 2005 study published in the American Journal of Clinical Nutrition found that men tired more quickly in workouts during a nine-week period of low zinc intake than they did during a nine-week period of adequate zinc intake. “There are also good studies showing that zinc cuts down the length and severity of symptoms during flu,” Russell adds.
  • How to use it: Take your zinc and magnesium supplement once a day before bed, but don’t wash it down with a glass of warm milk. “Calcium can interfere with zinc absorption,” says Russell. Also, note that most multivitamins have zinc and magnesium in them, so don’t overdo it.

See “Zinc Essentials” and “Magnesium: Your Body’s Spark Plug” to learn more about these essential minerals.

L-carnitine L-tartrate

  • What it is: L-carnitine L-tartrate is a compound comprised of the amino acids that help the body metabolize fat within cells.
  • What it does: L-carnitine L-tartrate has strong antioxidant effects in the body, protecting cell membranes against free radical damage, which occurs at high rates during exercise and as part of the normal aging process, Russell explains. Thus, long-term L-carnitine supplementation may slow the detrimental effects of aging on athletic performance.
  • The scientific case for it: A 2003 University of Connecticut study on humans found that L-carnitine L-tartrate (LCLT) helped muscle tissue recover from hypoxic (low-oxygen) exercise. And a 2008 University of Connecticut study again showed LCLT supplementation helped reduce markers of stress caused by exercise, though other studies have had conflicting results.
  • How to use it: A typical recommended dosage of acetyl L-carnitine is 500–1,000 mg, two times daily.

Alpha Lipoic Acid

  • What it is: Alpha lipoic acid (ALA) is a naturally occurring organic compound that plays a role in aerobic metabolism. Supplements can contain either the R-LA or S-LA isomer, or a mixture of both.
  • What it does: According to Russell, long-term supplementation with alpha lipoic acid may slow the detrimental effects of aging on athletic performance by increasing the body’s production of the antioxidant glutathione and preventing the decay of muscle cell mitochondria, where aerobic metabolism occurs. He notes that ALA also seems to increase insulin sensitivity, which plays a role in the aging and recovery process.
  • The scientific case for it: A 2008 study at the University of California–Irvine found that alpha lipoic acid slowed the aging-related decay of mitochondria in the brain cells of laboratory animals.
  • How to use it: Russell recommends a dosage of 50–100 mg, twice daily. “I would look for the R-isomer (R-LA), not the S-isomer, which is cheaper to produce but not as bio-available,” he adds.


  • What it is: Caffeine is a nervous system stimulant.
  • What it does: Caffeine use before exercise is proven to enhance performance in events ranging from short sprints to ultra-endurance races, Antonio says.
  • The scientific case for it: A study at the University of Hull, England, found that acute caffeine ingestion significantly increased time to exhaustion in an endurance exercise test.
  • How to use it: Consume 6 mg per kilogram of body weight (8 mg per kg if you’re a regular caffeine user) 30 minutes before competition. But since overuse of caffeine can, over time, increase the stress hormone cortisol in the body, use it sparingly.


  • What it is: N-acetylcysteine (NAC) is an antioxidant that replenishes muscle stores as glutathione, which prevents fatigue caused by free-radical formation during exercise.
  • What it does: NAC delays muscle fatigue in healthy adults during exercise, says Portman.
  • The scientific case for it: According to a 2008 University of Kentucky review, NAC has been shown to inhibit fatigue in healthy adults during exercise. “Scientists administered n-acetylcysteine to cyclists during an extended exercise bout and found there was a delay in muscle fatigue,” says Portman.
  • Who it’s for: Athletes competing in all sports where performance is limited by muscle fatigue.
  • How to use it: Portman recommends a dosage of 700 mg of n-acetylcysteine daily.

Top Picks

Here are the best supplements for each of three main goals, according to our experts.

Supplements to Build Muscle

  • Creatine monohydrate
  • Amino acid mix

Best Supplements to Improve Endurance and Boost Athletic Performance

  • Caffeine
  • Beta-alanine

Speeding Recovery

  • Amino acid mix
  • Green-foods antioxidant supplement

How to Pick a Quality Supplement

Within any given supplement category, the products may look more or less the same. But there can be big differences in ingredients, quality and effectiveness. How do you distinguish the best from the rest? Here are some tips from Shawn Talbott, PhD, research director of SupplementWatch (, a site that has been evaluating and reviewing dietary supplements since 1999.

  1. Choose supplements whose benefits are supported by published scientific research. “Don’t just buy the same type of supplement that was tested,” says Talbott. “Buy the same brand.”
  2. Learn to read supplement labels. Things to look for include the right form of an active ingredient (for example, Talbott says, one form of a supplement may be more effective than another) and the right amount of an active ingredient (some supplements include ingredients levels too low to be effective).
  3. Ignore everything else. Neither label claims, nor testimonials or price is a reliable source of information about the quality and potential effectiveness of a dietary supplement, says Talbott.

Dos and Don’ts


  • Research the type of supplement you’re considering and compare brands before you buy.
  • Choose supplements that are relevant to your needs. For example, creatine monohydrate, while helpful to strength athletes, has nothing to offer distance runners.


  • Don’t continue using a product if it causes side effects.
  • Don’t use a supplement as substitute for a healthy diet or proper training.

Matt Fitzgerald is a running and triathlon expert and has authored and coauthored several books, including Maximum Strength with Eric Cressey.

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