Or, even worse, you put on a few pounds.
Doucet, a professor at the University of Ottawa, says that people grossly overestimate the amount of calories they burn while exercising — and then they treat themselves by eating more.
The solution: If you hope to lose weight through exercise, eat the same as you did before you started working out. Or, for more weight loss, eat even less than your old pre-exercise self.
Doucet's study, published in the Journal of Sports Medicine and Physical Fitness, showed that people who burned 200 calories by brisk walking thought they'd burned a whopping 825.
Then, placed in a buffet setting and told to eat the number of calories they thought they'd burned, they overcompensated, eating on average 360 calories more than what they'd burned exercising.
If they kept exercising and eating at that pace, instead of losing weight, they'd gain a pound in just 10 days.
Exercisers think, "Now I can reward myself by sitting down and having an extra snack," Doucet says. "You have two Oreo cookies and your workout is pretty much annihilated."
To see how many calories you'll burn through exercise, there are many online calculators, like the Get Moving Calculator at caloriecontrol.org.
One more practical tip from Doucet: Stay away from caloric sports drinks. Instead? Drink plenty of water.
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