If you want to get rid of 300 calories daily, you can either cut out 2 ounces of potato chips or run 3 miles in the park every day, Klein noted.
“It’s very difficult to comply with a long-term physical activity program,” he said. “It’s just more difficult to do that than just reducing food intake.”
Klein wishes there were more tables posted in gyms showing the amount of physical activity required to burn common foods.
2. Exercise makes you eat more
Exercise is quite good at burning calories, but it also ends up making us hungrier, said Christopher Ochner, assistant professor of psychiatry and adolescent medicine at the Icahn School of Medicine at Mount Sinai in New York.
People often don’t notice, but they end up eating almost precisely the exact number of calories they burned during a workout in a phenomenon called “caloric compensation,” Ochner noted.
“We make up for the calories burned during exercise,” he said. “If I work out heavy, I know the next day I’m starving.”
Ochner tells people who are beginning a diet not increase their exercise for at least a month or two until they’re used to the weight loss plan.
3. You “reward” yourself for working out
Made it to yoga class? You indulge in a big sugary smoothie afterwards to congratulate yourself. Completed that killer strength session? An extra helping of pasta hits the spot — you’ve earned it!
If your goal is to slim down, that type of thinking defeats the purpose.
“If the reward means eating food… that would counteract the beneficial effect of exercise on body weight,” Klein said.
4. Your exercise regimen makes you move less overall
After you come back from the gym, you either feel like you’ve done your “duty” for the day or you’re so tired that you can barely move. Maybe you will take the escalator rather than the stairs after all, or drive to the nearby store rather than walk.
It all adds up to being less active — on average — than before you started your exercise routine.
“It’s a 24/7 energy balance equation. If you exercise aggressively for one hour and then you’re very sedentary for 23 hours… that will really overcome the calories you burn during exercise,” Klein said.
He pointed to a study that found older adults who exercised for one hour every day didn’t actually change their daily total energy expenditure at all because they were much more sedentary after their workout.
if you want to lose weight, Klein offered these tips:
- Reduce your calorie intake. One of the best ways to do that is portion control — cut the amount of calories you eat at each meal.
- Cut down on snacks and beverages that might have high calories.
- Remember that liquid calories count even though we don’t seem to be as much aware of them as solid calories.
- Exercise is an important adjunct to calorie restriction for people who are obese or overweight and want to lose weight, but exercise won’t have a very pronounced effect on weight loss.