There’s the idea out there that you should build muscle to raise your metabolism. That is a mistake that we in the industry should rectify. Instead, we should be emphasizing muscle’s positive effect on body chemistry.
Muscle and Metabolism – What’s The Number?
Muscle is indeed more metabolically active than fat, however, the amount of calorie burn that muscle accounts for is actually pretty small. The estimate that seems to enjoy the most agreement amongst the sources I found is between 5 and 10 kcal per pound of muscle per day. That means 10 pounds of muscle would burn maximum 100 calories more per day. Even thinking about that number though is pretty shaky ground because muscle metabolism varies depending on the circumstances, such as whether or not the muscle is active or at rest. If you would like to understand more about this problem, I suggest reading here. Suffice it to say, the benefits of muscle on daily calorie expenditure is over-simplified and over-emphasized.
Muscle and Metabolism – The Better Reason
There is a good reason to build muscle that is related to your metabolism. Muscles and body fat both regulate hormones. When the ratio of muscle to fat is well balanced and when you use that muscle regularly, your body chemistry is well balanced. Body chemistry, we are learning, is probably the real story when it comes to weight and health.
Conclusion
There is an over-emphasis on the role of calories in fitness – something I have written about often before – and this case is another extension of that. The trouble with this is that it creates false expectations while de-emphasizing other important benefits. Fitness has too much to offer to be getting bogged down in false promises and wild exaggerations. Work out and build muscle, it will do great things for you, but to lose a few pounds, focus on diet.
Epilogue
I was surprised to discover that it is not so easy to find an answer to questions like, “what is the metabolic rate of muscle” or “muscle’s effect on metabolism?” Similarly, we are just beginning to get a better understanding of body chemistry and the mechanisms behind weight gain, type II diabetes, and metabolic syndrome so who knows what we might discover in the future. For now, know that there are many other important things to consider besides calorie burn when choosing your exercise.
Resources:
Evaluation of Specific Metabolic Rates of Major Organs and Tissues – Muscle metabolism sited at 6 kcal/pound per day.
A Pound of Muscle Burns 30-50 Kcal/Day, Really… – This is a great breakdown of muscle’s role in metabolism from the NCSF. Although, I think they have an error in their metabolic rate. (I think they meant to write kcal/day, rather /hour in their equation)
Controversies In Metabolism – Here’s an academic description from the University of New Mexico
The Myth About Muscle And Metabolism – This article about muscle and metabolism provides a pretty good way to think about the issues. It’s worth a read.
How Many Calories Does 1lb Of Muscle Burn?
Muscle Mass Knocks Out Insulin Resistance – Results of a research study on muscle mass and insulin resistance.
All About Insulin – One of Precision Nutrition’s comprehensive articles.
Yes, Beautifully Written!