^ Mann, T; Tomiyama, AJ; Westling, E; Lew, AM; Samuels, B; Chatman, J (April 2007). "Medicare's search for effective obesity treatments: diets are not the answer". The American Psychologist. 62 (3): 220–33. CiteSeerX 10.1.1.666.7484. doi:10.1037/0003-066x.62.3.220. PMID 17469900. In sum, there is little support for the notion that diets ["severely restricting one’s calorie intake"] lead to lasting weight loss or health benefits.
“Most people overestimate the calories they burn on a run,” says Angela Rubin, USAT Level I triathlon coach and studio manager of Precision Running Lab at Equinox in Boston. As a very general estimation, you burn about 100 calories per mile (use this calculator to determine how many calories you burn based on your weight). So if you run two or three miles, you’ll burn about 200 to 300 calories—a solid workout.
At its core, burning fat comes down to the process of lipolysis—the breaking down of fat lipids, explains Seedman. This happens in the mitochondria of the muscles, or the powerhouses of the cells, responsible for generating the energy our cells need to do their jobs. Exercise has been shown to improve mitochondria function, which then promotes fat breakdown, Seedman adds. Plus, working out helps regulate pretty much all the hormones that optimize fat loss.