It's time for the article that should hopefully shape the rest of your weight loss journey for the better. Let's first start out with a fact: your metabolism, or your body's ability to burn calories, has a ceiling. We can increase the number of calories we burn in a day with activity, but there are limits. If all we do is sit on a couch versus running three miles, we will burn more calories. However, if we run six miles versus three miles, we see the increase of calories burned at this distance is less than the 0 to 3 mile option.