Truth: Your workout probably doesn't burn as many calories as you think.
A 30-minute run at a moderate 10-minute-per-mile pace burns just under 300 calories. So if you indulge in a cheeseburger, fries, and a beer, that's well over 700 calories. For weight loss, it's all about simple math: you need to burn or cut out 500 calories a day to lose a pound a week. After that 300-calorie-burning run, you would still need to cut out 200 calories from your diet. Exercising should definitely be part of your weight-loss plan, but so should monitoring your calorie intake.