If you want to lose weight, you need to eat fewer calories than you burn. That’s simple physics, and there’s no way around it.

Exercise usually burns somewhere between one hundred and five hundred calories per hour, depending on how intense it is and how much of your body it uses. On the other hand, you can easily cut back your intake by a thousand calories a day with a few small changes to your diet. That’s why weight loss is commonly said to be 70% diet and 30% exercise.