How Many Calories Does Muscle Really Burn?

You've probably heard that muscle burns more calories than fat does and that's true. Muscle is more metabolically active than fat, but the question is just how many more calories does muscle burn?

Over the years, experts have come up with a variety of numbers, anywhere from burning 6 calories a day to up to 100 calories a day per pound of muscle. Which number is right? Just how much can you tweak your metabolism by adding muscle? There isn't always a hard and fast answer, but there are some clues that can point us in the right direction.

Most experts, when they're studying to become fitness professionals, hear that one pound of muscle can burn up to 50 calories a day. A pound of fat was said to burn only about 2 calories a day. When you look at those numbers, you may realize that, if you put on just 5 pounds of muscle (which is a challenge, even for young men), you could burn an extra 250 calories a day—for free. The problem with these numbers is that there aren't any real studies to back them up.

While the 50 calories a day theory still circulates, more experts, including Dr. Cedric X. Bryant, the American Council on Exercise's Chief Science Officer, suggest a pound of muscle only burns about 6 to 7 calories a day, based on research published by McClave and Snider in 2001. Obviously, that's a big difference from the 50 many have believed. It is still three times more calories than are burned by a pound of fat.​

The confusion exists because of different studies using different ways to test metabolic changes after exercise. There are other mechanisms involved in metabolism as well that can affect how many calories you burn—gender, age, fitness level, how active you are, and more. Because of that, there's still plenty of controversy about how much exercise really influences metabolism.

As a result, there isn't an exact number. Just like your target heart rate zones or the number of calories you burn exercising isn't exact, neither is this.

Some people may get discouraged, thinking that they aren't burning as many calories as they thought they would. You might start to wonder, what's the point of lifting weights at all? Maybe you aren't going to burn an extra 250 calories a day by putting on muscle, but you are changing your metabolism.

Whether you believe muscle burns 6 calories or 60 doesn't change the fact that strength training is incredibly important for losing fat and keeping your body strong and healthy. In fact, maintaining your muscle mass as well as gaining more lean tissue is often what keeps people from gaining weight as they get older. That's a powerful benefit.

Just some of the benefits include:

• High-intensity strength training can actually help you burn extra calories for hours after your workout, known as afterburn
• Prevents the loss of lean body mass that happens from dieting and/or aging. Weight gain often happens as your metabolism slow down with age. Lifting weights can help mitigate some of that weight gain and keep you strong and fit.
• While strength training doesn't burn as many calories in one sitting as cardio, it does contribute to your overall calorie expenditure.
• It changes your body composition, which helps shape your body and keep you healthy.
• It strengthens bones and connective tissue along with muscles.
• It keeps you strong and active as you get older.
• It improves coordination and balance and may help prevent injuries.

The bottom line is, we simply can't measure every aspect of fitness. We don't have tools sophisticated enough to measure things that are happening inside our muscle fibers or inside or very cells as we exercise.

What you see in the mirror and on the scale is what you often focus on. If you don't see the changes you want, you may get discouraged thinking nothing is working. Results come with time and consistency. Ask any fit person how long it took to see real changes and they might say months, even years.

Strength training is important for almost any fitness goal, whether you want to lose fat, gain muscle, or just get in better condition. Focusing on the process of getting your body stronger and fitter will often motivate you more than worrying about how many calories you're burning.