Often, the more you exercise, the hungrier you get and—
• the more you eat, or
• the more your believe you “deserve” to eat, or
• the more you want to eat as a reward for having both gotten to the gym and survived the exercise session.
But if you spend 60 minutes in a spin class and burn off 600 calories, only to reward yourself with 12 Oreos (600 calories), you quickly wipe out your weight loss efforts in less than 3 minutes.
The effects of exercise on weight loss are complex and unclear. We know among older people (56-78 years) who participated in a vigorous walking program, daily calorie needs remained about the same (2,400 without exercise, 2,480 with exercise). How could that be? Well, the participants napped more and were 62% less active throughout the rest of their day. (1) Another study with post-menopausal women found the same results from eight weeks of moderate exercise training. Their 24-hour energy expenditure remained similar from the start to the end of the program. (2) The bottom line: You have to eat according to your whole day’s activity level, not according to how hard your trained that day.