Strengthen your resistance by saying no

That's another thing Beck mentions. She says that every time you go ahead and cave to your cravings, you are strengthening your "giving in" muscle. But when you say no, you strengthen your "resistance" muscle. It's true. Every time you give in, it makes it easier to give in again next time. But after a few days of resisting, it gets easier to resist. Now I don't have near the struggle saying No to myself as I used to. Which muscle do you want to strengthen? Think about it.
(taken from escape from obesity blog)