The 50 Calorie Per Pound of Muscle Myth

I don't know how many times I've heard the saying, "You increase your metabolism by 50 calories for every pound of muscle you add to your body."

50 calories per pound????   Really????

Let's take a look at this.  I'm about 180 pounds.  When I first started weight lifting, I weighed about 135 pounds.  I've added a little bit of body fat since then, so let's be conservative and say I've gained 30 pounds of muscle since I started weight training.

If I've gained 30 pounds of muscle, that means that my metabolism should have increased by 50 x 30 = 1,500 calories.

I've had my resting metabolic rate (RMR) officially tested.  The last time it was measured, it was 1,671 calories per day.

Now, if my RMR increased by 1,500 calories since I first started weight training, then that would mean my RMR started out at only 171 calories per day.

That is completely impossible.  Nobody has a resting metabolic rate that low, unless you're dead.

Building muscle does not increase your metabolism by 50 calories per day.  The real number is only 6 calories per pound on average.

So my 30 pounds of extra muscle has increased my metabolism by about 180 calories...not 1,500.

Adding muscle doesn't boost your metabolism all that much.  Yes, it does a little bit, but you'll get more bang for your buck by simply being more active throughout the day.

Don't get me wrong.  I'm not saying building muscle and strength training is not important.  It's extremely important.  It improves strength, it improves appearance, it improves function in activities of daily living, and it increases bone density.  You also get a nice elevation of your metabolism of about 50-100 calories for 24 hours after your workout.  My point is that building muscle is over-rated for permanently increasing your metabolism and energy expenditure.

The "50 calories per pound" number appears to be a case of communal reinforcement.  This is the process by which a claim becomes a strong belief through repeated assertion by members of a community.  Someone, somewhere, at one time proclaimed this 50 calorie per pound number.  Other people heard it, believed it, and started telling their friends.  It has now been repeated so often by so many people everywhere that people have accepted the number without question.  Then you get doctors and other respected health professionals quoting the number, and it becomes permanently entrenched in our beliefs.

The fact is, muscle does not boost your metabolism all that much.  Building muscle is important....just don't expect it to make you a calorie burning machine.

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Jay Horn
11 years ago

Only me… Evidently.

Listen chief, post a pic.

Then I’ll listen more carefully….

Jay Horn
11 years ago

You built 30lbs of muscle? Are you sure you know what 30lbs of muscle looks like??

Does anyone else in here find this questionable??

Hell…. Forget the calorie expenditure arguments….

how many calories should i eat

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13 years ago

You RMR was officially calculated at 1671 calories But any RMR calculator I know off, from those more complex (where I guessed your stats a little) to those more approximate, says your RMR is way higher (from 1900 to 2100 calorie) Does that mean that every person who is trying to lose weight is working with overestimated numbers. On many forums I see people always claiming to petite young girls (5.2 feet and 110 pounds) how they should eat at least 2000 calories and to not fall victim of the mentality that they should eat little calories. It seems to… Read more »

13 years ago
Reply to  James Krieger

Keep it coming James! I love that you provide links to original research to back up what your write. Too often, the information I read seems to be rehashed lore that has gotten so far from the original source of scientific research. I have another suggestion for a different topic. I’m interested to know if there are studies comparing the effectiveness of various training techniques on maintaining and/or increasing bone density for women who are perimenopausal and beyond. For example, do low rep, high weight workouts do as well as a low weigh, higher rep workout? ie: Which is more… Read more »

13 years ago

Hi James,

Thanks for the article. The “50 calories per pound of muscle” was a claim that I never found any solid research behind so the links that you provided helped tremendously. However, do you know if there are any research on whether there’s any differences between the resting metabolic rate of type I, type IIa, and type IIb skeletal muscle fibers?

Also, if it’s worth anything, I feel that your debate with Fred wasn’t a total waste because I learned a lot from it.

Jordan D.
13 years ago

I’ve really been enjoying this debate. Great stuff. 🙂

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