Do Supplements Give Athletes an Edge?

Medically Reviewed by David Kiefer, MD on July 07, 2015
4 min read

You work hard to reach your athletic goals. You stick to your training program and to your nutrition plan. Now you want an edge over the competition. Is there a supplement that could give it to you?

Maybe, but results vary from person to person. When scientists study these products, mixed reviews are pretty common. Also, most research focuses on highly trained or pro athletes, so your results might be different. But if you're healthy and have no problems with your heart, kidneys, or liver, the most popular sports supplements are safe and inexpensive.

It's best to talk with your doctor before you take any product, even if it's natural, in case you have any conditions or take medications that it could affect.

Caffeine gives you a pick-me-up in the morning, and it can pick up your game, too. If you take it about 30 minutes before your race or game, it could improve your endurance. For long challenges, like a marathon, caffeine during the event can help, too.

“Studies have shown repeatedly that you can get improvements in performance, mainly in endurance-type exercise, with caffeine,” says Janet Rankin, PhD, professor in human nutrition, foods, and exercise at Virginia Tech.

Tennis players, cyclists, soccer players, runners, rowers, and others got an edge from caffeine in scientific studies. In some trials, the stimulant boosted athletes’ speed. In others, it helped them last longer before they spent all their energy. Some studies show that it can curb soreness after exercise, too. This means you could get back to your training sooner.

You can get caffeine from energy drinks and shots, tablets, chewing gum, sport gels, and sprays. Each product will give you different doses, so read the label before you take it.

“You don’t need all that much caffeine to get the effect,” Rankin says. “And it is possible to overdo it.” No matter what form you take, make sure you don’t get more than 400 milligrams a day. And don’t forget to count your other daily sources of caffeine -- there’s about 100 milligrams in your morning coffee.

Too much caffeine can cause headaches, irritability, stomach upset, dehydration, and trouble sleeping.

Are you a sprinter or weight lifter? Creatine monohydrate could help with these and other repeated short bouts of intense exercise. It doesn’t seem to benefit players of other types of sports. And, like studies of many supplements, not all studies show that it benefits athletes.

Your body makes creatine naturally, and your muscles use it to do high-intensity exercise. When you do a lot of reps, you use up your natural store of it. That’s one reason your tenth rep is so much harder than your first. A supplement boosts the amount your body has to work with. You also can get creatine from beef and pork. If you already eat plenty of these, you won’t notice as much of a difference from a supplement as a vegetarian might notice.

“For very short-term bouts of exercise, creatine supplementation seems to aid in recovery,” says Thomas Sherman, PhD, professor in pharmacology and physiology at Georgetown University Medical Center in Washington, DC.

Experts consider creatine safe for healthy people. Some people take a higher dose for the first week -- about four servings of 5 grams each per day -- to “load” their muscles with the supplement. Then they drop to a “maintenance” dose of about 2 grams per day. Others skip the loading phase and start with the lower dose.

Some studies have shown that creatine could increase fat and not muscle. There’s also evidence that high doses could cause kidney, liver, or heart damage, but it's unclear how much might be too much.

When you do short bouts of exercise at maximum effort for 30 to 90 seconds (think indoor cycling classes), your muscles make a lot of lactic acid. That’s what makes you “feel the burn.” Athletes take beta-alanine in a capsule or a drink powder to curb that burn so they can push through their workout.

Does it work? Cyclists and runners who took beta-alanine for 4 weeks improved their game in scientific studies. But not all studies agree.

“Some studies show a benefit. Others don’t,” Rankin says. “So it’s not completely clear yet. We need more studies on it, but it’s not one that I’m worried about people trying.”

Amino acids are the building blocks of protein. The branched chain types are the three amino acids that muscles can use for energy. Athletes take them after workouts as tablets, gels, or drink powders to spur muscle growth.

Exercise makes your muscles grow by first injuring or breaking them down. When the tissue rebuilds, it gets bigger. Some studies show that branched chain amino acid supplements reduce muscle breakdown. If you have to lose muscle before you can gain it, the idea is that the products could cut the amount you need to lose before you start to get it back.

While these supplements might work, don’t expect dramatic results. “Exercise stimulates muscle [growth] anyway. So taking amino acids probably isn’t physiologically very significant, but it’s also not harmful,” Sherman says.

Like branched chain amino acids, many athletes take whey protein, usually in a protein shake, after workouts to try to curb muscle damage and boost growth.

“There’s a window of about at least 30 minutes after you stop exercising during which you can take in protein and promote [growth] of lean muscle mass,” Sherman says. A number of scientific studies show that whey protein after exercise helps reduce muscle damage or promotes its growth.

Whey protein seems to work best after resistance exercise, like weight training, Rankin says. But you don’t have to get the nutrient from a supplement. A high-protein meal after a workout would do the job, too. Whey protein on top of that might give you an extra boost.