Sports Supplements: Whey, Creatine, Branch-Chain Amino Acids, and More

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 for Endurance

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.