Deciding what supplement to take can be a tall task. Companies are constantly marketing their latest muscle-building “breakthrough” product, which may sound tempting. But don’t be fooled. Only a few muscle-building supplements have actually been proven by science to effectively and safely build lean-muscle mass.

Effective Muscle Builders

Creatine

With over 200 published human studies, creatine monohydrate is without a doubt the number one muscle-building supplement that works. Creatine increases muscle protein and glycogen content, and it delays fatigue during repeated, high-intensity bouts of exercise. It’s especially helpful for athletes who don’t regularly consume meat. (Learn more about the benefits of creatine.)

Take five grams per day either before or after training (take it with a meal on off-days), and co-ingest it with some carbohydrates or protein to help your muscles absorb it more effectively.

Protein

The simplest way to gain muscle mass is to eat more calories and strength train. And bigger muscles require more protein, usually twice as much as “normal” sedentary chumps who don’t work out typically consume.

Most athletes should consume at least 25 grams of protein at every meal. At five meals per day, that’s a total of 125 grams—an amount that will promote solid lean mass gains. (Athletes weighing over 200 pounds should shoot for about 30 grams of protein per meal.) Breakfast, after a workout and before bed are the most important times to take in high-quality protein. (Read: Keys to a Post-Game Meal.)

HMB (hydroxy beta methylbutyrate)

HMB, a metabolite of the amino acid leucine, isn’t necessarily “new.” However, there’s been a resurgence of quality research that shows it can promote lean-muscle gains during periods of over-reaching (i.e., when you push your body to its limit) by accelerating muscle repair.

Take 1.5 grams in the morning and another 1.5 grams in the early afternoon. Take it only when your body is being taxed, like during two-a-day practices, pre-season and perhaps during a season.

Muscle-Building Supplement Fails

Glutamine

There’s simply no data supporting the effects of glutamine supplementation on muscle growth in healthy humans. None! Taking it won’t hurt you, and it may help you avoid an illness, because it’s good fuel for your immune system. However, don’t expect it to be the “game changer” that most companies make it out to be.

Testosterone Boosters

It’s no secret that anabolic steroids (i.e., drugs that mimic testosterone) build muscle mass. However, existing supplements that claim to boost testosterone, like Tribulus Terrestris, D-Aspartic Acid, Eurycoma Longifolia and Fenugreek, have no scientific support proving that they are anabolic agents in young and healthy men. Even if they do boost testosterone slightly, the effect is not great enough in magnitude or duration to cause muscle growth. A much better approach than using alleged testosterone boosters is to train harder, sleep more and eat more high-quality food (and take creatine, protein and HMB).

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