There’s no denying the science that the relationship between caloric-input and caloric-output affect weight, whether it’s maintaining, gaining, or losing. When it comes to biological truisms, there’s no way to debate the facts. How and what we input and output makes all the difference.

The Science

In their article, Why You Shouldn’t Exercise to Lose Weight, Julia Belluz and Javier Zarracina point to a large number of studies in order to present a justification for the title of their piece. One such study goes back to 1958 where researcher Max Wishnofsky outlined a rule to the “calories-in, calories-out” theory.
Many medically based organizations, even the Mayo Clinic, still espouse that a pound of fat equals approximately 3,500 calories. If a person cuts out about 500 calories a day, he/she will lose about a pound a week. The authors are not arguing if this is true, they are saying that in order to lose weight, you don’t necessarily have to exercise.
The worry in presenting such a case is that you may lead people down an unhealthy path. Exercise increases metabolism, lowers blood pressure and cholesterol levels, and reduces the risk of heart attack, stroke and Type 2 diabetes. Negating the benefit of exercise isn’t compensatory to making a case that you can lose weight just by eating less.

Just Exercise

Here’s where Belluz and Zarracina do present a plausible debate: It’s difficult to lose weight simply by exercising more. An obesity researcher at the National Institutes of Health (NIH) explains that there are three main components to how we burn calories (energy expenditure). The first (and the one that uses the most) is our basal metabolic rate.
Those are the calories we use when our body is at rest. The second component is the energy we use to digest food, and the third is the energy we use when we exercise or run around all day. If 70-90% of our total energy expenditure is used in those first two components, that only leaves about 10% for physical activity. That’s not a lot. Exercise alone isn’t going to make a huge difference in our ability to burn more calories.
Another strong point they made is based on a 2009 study, which showed that people actually increased their food intake after exercise. They were either hungrier, or they believed they burned off more calories than they actually did.

More Science

A further study pointed out that after a workout, some people are liable to rest after, using fewer calories on random physical everyday activity than they normally would. They may even change how they do things, like get in the car instead of walk, or take the elevator instead of the stairs. These “compensatory behaviors” may make us unconsciously overall less active (as a result of exercise.)
The best research, however, shows that successful weight-loss comes from cutting calories, decreasing high-fat foods, being mindful of portions, and exercising regularly. To read more about weight-loss, metabolism, and exercise, check out previous articles on www.GetThrive.com