Muscles Vs. Fat Calories Burned

Calories are simply units of energy converted from the food we eat that are used by the body. They fuel a range of everyday bodily functions from moving and breathing to producing hormones and growing cells. The amount of calories burned each day varies from person to person, based on a number of different factors, including your age, height, sex and body composition. But muscle mass also plays a significant role in the disbursal of calories.

Muscle

Muscle burns more calories than fat, according to the Mayo Clinic. Even when your body is at rest, you burn more calories with muscle mass than you do without. This is largely due to the fact that muscle is "metabolically" more active than fat, causing an increase in calories burned on any given day.

Calories Burned

Claims vary greatly on the average calories burned by muscle and by fat, which can make it difficult to discern a precise number. Some people claim that a pound of muscle burns upward of 50 calories a day, while others argue that each pound burns only an additional 5 calories over a 24-hour period. Regardless of who is correct, you're still burning more calories with muscle than with fat, since 1 lb. of fat is said to burn a total of 3 calories a day.

Effects

There's also some indication that it isn't simply the muscle that raises your metabolism and thereby burns more calories than fat. It's actually the process of repair that occurs after resistance or weight training that increases the amount of calories burned. When you lift weights, you're basically tearing down your muscles. Your body responds by repairing the affected tissue, expending more energy than normal, which ultimately burns more calories than fat.

Time Frame

In a study published in the "American Journal of Clinical Nutrition" performed at Tufts University in 1994 and another published in the "Journal of Applied Physiology" executed at the University of Maryland in 1994, participants took part in progressive resistance training programs a total of three times a week over the course of 12 and 16 weeks, respectively. Each session was around 30 minutes in length and contained an average of 140 total repetitions, broken out into various weight-bearing exercises. Most participants saw between 34 and 35 additional calories burned with each pound of muscle, reducing body fat.

Misconceptions

The fact that muscle burns more calories than fat doesn't mean exercise should only include weight-bearing activities. It's also important to include aerobic workouts, such as running, biking, walking or swimming. While these activities don't necessarily increase muscle mass at the same rate as lifting weights, they can help to maintain lean muscle and burn additional calories.