Another myth busted: protein for building muscle

It's a bodybuilding tenet that building muscle requires eating a lot of protein. You can see why it seems to make sense to those who don't understand physiology: to make more muscle, something made of protein, you need more protein, right?

We hope we don't need to tell you that the body doesn't work that way. Whether it's collagen for joints, skin, and hair, or protein for muscle, consuming more of a certain type of tissue doesn't mean your body creates or utilizes more of that tissue.

Today's article demonstrates that truth with a randomized controlled trial including just over 150 people who were at least 65 years of age - people who are more likely to benefit from increased protein intake (Am J Clin Nutr 2020;112:113-128).

Funded by a grant from Meat and Livestock, Australia Ltd., the authors of the study recruited participants from Melbourne, Australia and surrounding environs who were at least 65, were otherwise free of chronic disease, and were neither actively pursuing resistance training nor otherwise regular exercisers. To participate in the study the participants had to have their physician's clearance to join an exercise program.

For 24 weeks (6 months) the participants exercised three days per week in a personal-trainer-led exercise program that included both aerobic training such as cycling or walking on a treadmill as well as progressive resistance training such as using free weights or exercise machines.

Half of the participants were provided with 220 grams of lean red meat (about 7 3/4 ounces) for them to consume on each of their training days, while on the other four days of the week the participants followed their usual diet.

The other half of the participants "were instructed to consume their usual diet, incorporating a minimum of one-half cup of uncooked rice or pasta or 1 medium-sized potato" on each of their training days, and like the other participants, following their usual diet on non-training days.

If it were true that consuming more protein meant building more muscle, those who were consuming that extra lean red meat would have greater muscle mass and would be stronger than those who did not consume that extra protein. Right?

Not so.

All participants underwent the same ultra-sensitive scans to ascertain their lean mass, fat mass, and muscle density at various points of the body both before the study began and after the 6 months of resistance training. Statistically speaking, there was no significant difference between those who consumed extra protein and those who continued (basically) with their regular diet: both gained about the same amount of muscle mass and strength.

What this means for you

Your body has the amazing ability to build muscle (and fat) out of whatever fuel it is provided. Yes, you should make sure that the calories you consume are of the highest quality - for reasons that go far beyond building muscle. But do you need to consume protein to build muscle? No.

(Meat and Livestock, Australia Ltd. were likely disappointed with this study.)

First posted: July 22, 2020