How to Use RMR to Build Muscle

To determine a daily caloric intake target to build muscle, you need to consider your resting metabolic rate (RMR) as well as your  daily caloric burn from your normal activity level. To do this, you need to calculate your Total Daily Energy Expenditure (TDEE) using your RMR.

Determining your Total Daily Energy Expenditure

Your TDEE is an estimation of how many calories you burn each day,  including physical activity. This is simply your RMR plus the calories you burn from physical activity; it's is easy to calculate based on your activity level using the chart below.

Your RMR makes up around 60-  75% of your TDEE while the Thermic Effect of Food (TEF, or the energy needed to digest food) makes up about 10%.

Using TDEE to gain muscle

TDEE is what your body requires in a day to maintain your current weight. If you want to build muscle, you need to consume more calories than your TDEE while doing adequate muscle-building exercises.

How much should I eat to build muscle?

A good target for lean muscle gain is to consume about 110% to 120% of your TDEE (i.e. an extra 10% - 20%).

This daily caloric increase is enough to gain muscle without excess calories that could cause fat gain as well. If you are trying to gain more muscle quicker, then aiming to consume more calories within that range will be better (when coupled with appropriate resistance training). However, there is a limit to muscle growth rate, which means going over that energy requirement will lead to the excess energy being stored as fat instead. Your hormonal profile affects this muscle growth limit as well.

We recommend trying a daily calorie target for a few weeks while tracking progress. If you aren’t seeing results, then adjust your calories up.

What you eat matters

While your total caloric intake is important for weight gain, what you eat and the nutritional contents of those calories are also very important for body composition. Paying attention to macronutrients (i.e. protein, carbs, and fat) and eating enough micronutrients will provide the needed resources to build muscle. They will also help improve recovery, sleep, inflammation, and countless other areas of your well-being that indirectly help you build and maintain muscle.

To build muscle, you need to focus on eating adequate protein (the building blocks of muscle). The American Dietetic Association, Dietitians of Canada, American College of Sports Medicine, and the International Association of Athletics Federations have all stated that a minimum of 0.7 grams of protein per pound of body weight is sufficient for gaining muscle or losing fat.

To support building lean muscle tissue and minimizing fat gain, many experts recommend following these guidelines for macronutrients consumption:

• Protein: 1 gram per pound of body weight; from healthy sources
• Fat: At least 0.3 grams per pound of body weight, depending on total calories; from healthy sources
• Carbs: The remainder of calories; from healthy sources full of micronutrients

Importance of exercise for building muscle

Doing strength and resistance training is key to building muscle. Strength exercises vary greatly, from bodyweight exercises to resistance and weight training. The exercises you do will depend on your training experience and muscle-building goals.

And remember to make sure that the exercise program you are doing is factored into your TDEE so you are matching your calorie needs appropriately.