I’ve always wondered which matters most when trying to lose weight – diet or exercise. How much should we trust the messages we receive about this question? When I make my drive to work, I pass multiple gyms. At 6:45 a.m., all are busy. I see countless ads on TV for exercise equipment showing dramatic before and after results – with no mention of diet. On the other hand, I see just as many ads promising you will lose 10 pounds or more in one month by simply ordering and eating their delicious meals – again with no mention at all of exercise. So which should we believe?
With our love of food and society’s idealized image of six-pack abs, it’s no surprise that many in the U.S. turn to exercise to rein in their extra pounds. It seems odd to me that some value a $40-50 per-month gym membership, yet they complain about the cost of produce and other whole foods. What they may not know, however, is that there is a lot of science to suggest exercise is not the magic bullet we are searching for.
I don’t want to downplay exercise. It is extremely important for your overall health and well-being. Increasing physical activity can help you decrease blood pressure and cholesterol levels and lower your risk of certain chronic diseases.
However, when it comes to losing weight, it is all about energy balance. If you want to lose weight, the amount of energy you take in from food and drink should be less than the amount of energy you use each day. Seventy to ninety percent of energy use comes from two bodily processes: The energy it takes to break down food in our body and our basal metabolic rate (BMR).
BMR is the amount of energy your body uses to, well, exist. This can be good news for those of us with mobility impairments who use a lot of energy, to walk, get dressed, bathe, or do ordinary daily activities. The bad news is mobility impairments can make you more sedentary, which lowers your BMR and makes it much easier to gain weight.
Since we don’t have much control over the 70-90 percent of energy expenditure that makes up our BMR, focusing our efforts on what we eat and how much we exercise may lead to better weight loss results. Seeing a fast food billboard on your way home, you may think, “It’s been a long day, I don’t want to cook. I’ll just spend an extra half hour at the gym after dinner to make up for it.” However, it doesn’t work that way.
You may have to spend an hour on the treadmill to work off all the calories you would take in by drinking a can of Coca-Cola. You might have to be there all day if you factored in your whole meal. This article from Vox breaks the topic down further.
The key point? Exercise and diet are not equal when it comes to weight loss. Don’t stop exercising but remember, the extra hour in the gym won’t make up for happy hour calories.
-By Rachel Markley, M.P.H., research assistant for the GoWoman study, Center for Research on Women with Disabilities at Baylor College of Medicine and TIRR-Memorial Hermann