When it comes to exercising, we’ve been told the same thing our entire lives - exercise is central to losing weight, and the more you work out, the more calories you’ll burn - and the slimmer you’ll get.
While exercise has a multitude of positive health benefits, studies increasingly show weight loss isn’t one of them.
Alexxai Kravitz, a neuroscientist and researcher at the National Institutes of Health, explained to Vox there are three main forms of energy expenditure: 1) Your basal metabolic rate - or the amount of energy you expend while you’re at rest; 2) The energy needed to break down food; and 3) energy expended from physical activity.
The vast majority of your total energy expenditure - 60 to 80% - is from your basal metabolic rate. And you have very little control over your natural metabolism.
Another 10% of energy expenditure results from breaking down food.
So that means only 10 to 30% of your daily energy output comes from physical activity. And that’s any type of physical movement - not just exercise.
Kravitz said, “It’s not nothing, but it’s not nearly equal to food intake - which accounts for 100% of the energy intake in the body. This is why it’s not surprising that exercise leads to significant, but small, changes in weight.”
Dr. Tim Church, a professor of preventive medicine at the Pennington Biomedical Research Center, estimates 15% of people are actually hungrier after they exercise. Some people also use exercise as an excuse to slow down the rest of the day. These unconscious changes in our post-exercise activity are called compensatory behaviors.
So any food consumed as a “reward” for working out can offset a caloric deficit. Obesity research Kevin Hall said, “You work hard on that machine for an hour, and that work can be erased with five minutes of eating afterward.”
Remember, just because you went to spin class doesn’t mean you can treat yourself to cheeseburger. Switch it out for a salad instead.