Typically, a reverse diet is recommended post-weight loss because as you diet, your metabolism slows down and adapts to a lower calorie intake. To bring your metabolism back to normal and maintain your new weight on higher calories, it’s essential to slowly and methodically increase calories over time.
You can’t (and shouldn’t) stay on diet calories forever!
Increasing calories slowly over weeks and months rather than all at once, the body has time to adapt to the increased food intake. With each slight increase in calories, metabolism is triggered to burn through fuel faster. In this way, your metabolism can catch up to the surplus calories each week and burn through most of them, rather than allowing all of them to be stored as fat. Once a healthy metabolism is restored, you’ll have room to cut calories again, but this time from a higher food intake and a lower body weight.
Alternatively, if you’ve just finished your weight loss phase and want to gain weight and build muscle with heavy weight lifting, you can switch to the muscle gain goal. Like the reverse dieting goal, the muscle gain goal will put you in a calorie surplus to restore your metabolism—but it will also force you to regain a certain amount of weight each week.
If you don’t want to regain weight you should change your goal to a reverse diet rather than muscle gain after weight loss.