The human body naturally burns more calories to maintain a pound of muscle than it does to maintain a pound of fat. Therefore, the more muscle you build, the more calories your body will naturally burn each day at rest (breathing, sleeping, daily tasks). This means that just by building more lean muscle, you’ll significantly increase your metabolic rate and cause your body to burn more calories per day. In fact, “10 pounds of muscle would burn 50 calories a day spent at rest, while 10 pounds of fat would burn 20 calories” states Christopher Wharton, Ph.D., a certified personal trainer, and researcher at Yale University.