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Best Supplements for Working Out, According to Experts

Eating a highly nutritious diet? Uh-huh. Then consider something to add to your get-back-in-shape routine.
FACT CHECKED BY Olivia Tarantino

Everyone's looking for an edge. Whether you're an Olympic athlete or weekend tennis player, everyone wants something that'll provide a boost during exercise or competition. It takes more than pushing yourself physically to build your body or improve your performance; you need to supply your body with nutrients that'll maximize your effort.

Even if you eat enough carbohydrates, the chief macronutrient for energy to fuel endurance, and even if you eat a healthy diet (do you, really?), you probably don't get enough of the good stuff that'll make your body hum when you're huffing and puffing. Dietary supplements can fill those gaps.

We asked nutritionists and fitness experts for their must-have supplements for exercise and sports. Be forewarned: there are a lot of opinions out there and few iron-clad clinical studies supporting the claims. But you can do your own research to figure out what's worth a try for the goals you have in mind. This review of Dietary Supplements for Exercise and Athletic Performance from the National Institutes of Health, will help the next time you're considering buying, say, deer antler velvet, a Chinese supplement purported to have growth factors for building muscle.

And remember that dietary supplements are not regulated by the Food & Drug Administration as drugs. Many manufacturers make claims that may not be entirely true. What's more, because they are not rigorously controlled as pharmaceuticals, dietary supplements can contain ingredients that may interact with your prescription medicines. Talk with your doctor before taking any new dietary supplements and review our story on Popular Supplements with Hidden Dangers.

Protein Powder and Creatine Monohydrate


Protein is the building block of muscle. If you're doing vigorous exercise or resistance training, you are breaking down your muscle fibers and need protein to repair and rebuild them stronger than they were before, says certified sports nutritionist Hope Prenner, a National Academy of Sports Medicine Certified Personal Trainer on staff at "I strongly recommend supplementing with protein powder and creatine monohydrate, a natural substance found in muscle cells that is the first form of energy that the body burns through during strenuous exercise," she says.

READ MORE: The Best and Worst Protein Powders to Buy

A Plant-Based Recovery Supplement with Polyphenols

pomegranate extract

Polyphenols are micronutrients found in fruits and vegetables. One of the most effective of these phytonutrients is ellagitannin, which has been shown to reduce delayed onset muscle soreness (DOMS) that typically starts a day or two after a workout.

Ellagitannins are found in pomegranate extract, which is a key ingredient in Beachbody super trainer Autumn Calabrese's go-to post-workout drink Recover, a plant-based protein and polyphenol powder. "I feel good knowing I'm getting a high-quality source of vegan protein and phytonutrients to combat exercise-induced muscle soreness, speed recovery and restore my strength so I can do it all over again the next day," says Calabrese, author of Lose Weight Like Crazy Even If You Have a Crazy Life.

"Recover helps me stay consistent with my routine. At almost 41, I'm the fittest I've ever been." A serving of Recover contains 20 grams of pea protein; that's just about the maximum amount your body can use at one time to support muscle protein synthesis, according to a study in the Journal of the International Society of Sports Nutrition.

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Vitamin D

vitamin d

Exercise itself helps build bone. The forces you exert on your bones when exercising cause bones to become denser. But vitamin D is also essential for good bone health because our bodies do not effectively absorb calcium without it. "Supplementing with vitamin D is a good idea for athletes because it promotes bone health, which all athletes rely on for good performance," says Diana Gariglio-Clelland, RD, a nutritionist on staff at, and a certified diabetes education specialist. "It's estimated that over 40% of Americans are vitamin D deficient, so vitamin D is a worthwhile supplement to invest in for overall health." And it is well-researched in terms of benefits, something that can't be said of all dietary supplements, she says.

For more, check out The #1 Best Vitamin D Supplement to Take, Says Dietitian.

BCAAs (Branched-Chain Amino Acids)


The BCAAs valine, leucine, and isoleucine are essential amino acids your body gets from the proteins in dairy, meat, and legumes. For you chemistry buffs out there, "branched-chain" refers to their chemical structure. BCAA supplements are popular with weightlifters because they may enhance muscle growth and help prevent DOMS (delayed-onset muscle soreness). "One of the most important things to look for when choosing a BCAA supplement is the ratio of leucine to isoleucine and valine," says Jay Cowin, a certified sports nutrition advisor (CSNA) and the nutritionist/director of formulations for ASYSTEM.

"I recommend a supplement that uses a 2:1:1 since leucine plays the most important role in muscle protein synthesis while isoleucine helps process leucine. Valine helps reduce fatigue during your workout." The supplements are available in capsule or powder form. Cowin prefers the powder because it acts faster and delivers higher doses than BCAA capsules.



Arginine (L-arginine) is an amino acid that's often used to treat peripheral artery disease and erectile dysfunction because it affects nitric oxide production, relaxing blood vessels, and improving blood flow. But it's an exercise supplement, too. "It stimulates growth hormone to help grow muscle, build strength, and aid in recovery from vigorous workouts," says Cowin. "It's a precursor to creatine for natural performance enhancement." Cowin points out that arginine and other supplements often contain added ingredients like electrolytes, sweeteners, and gluten, which may cause negative reactions if you are sensitive to these additives. Check ingredient labels before buying.

Beet Root

beet root powder

Beetroot powder is made from the beet plant, a terrific source of nutrients like folate, manganese, potassium, iron, vitamin C, and fiber. "Beet root can help increase blood flow to help oxygenate exercisers' hard-working muscles," says Lauren Manaker, MS, RDN, a member of our Eat This, Not That! Medical Expert Board and a licensed dietitian for Zhou Nutrition, which makes Zhou Beet Complete, beetroot powder.

Studies have shown that beetroot powder can improve athletic performance by helping the mitochondria, the "energy engines" in your cells to work more efficiently during intense exercise. The key ingredient in beetroot is nitrate: a substance that helps your body produce nitric oxide, which dilates blood vessels, improves blood flow, and lowers blood pressure.

In addition, "the antioxidants in beet root may help combat the oxidative stress that may occur during a strenuous workout," says Manaker. "I recommend beetroot as an addition to a dietary regimen for those who exercise vigorously." You can read more about the potential for nitric oxide to boost resistance exercise in this study in The Journal of Strength Conditioning Research involving bench pressing at 60% of recreational athletes' one repetition maximum.


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Jamie Hickey, NASM, a certified trainer, nutritionist, and founder of Truism Fitness recommends quercetin supplements. "Quercetin (a flavonoid found in apples, tea, berries and red wine) is a well-studied antioxidant that can work to increase your endurance and act as an appetite suppressant," he says. "A variety of studies have found that quercetin supplementation increases exercise tolerance and muscle loss while decreasing markers of muscle degradation." One double-blind clinical trial of 60 male athletes in the International Journal of Preventive Medicine found that those who received quercetin capsules improved their lean body mass, basal metabolic rate, and total energy expenditure.

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Jeff Csatari
Jeff Csatari, a contributing writer for Eat This, Not That!, is responsible for editing Galvanized Media books and magazines and for advising journalism students through the Zinczenko New Media Center at Moravian University in Bethlehem, PA. Read more about Jeff