Susan after

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Susan Asbjornson Ziegler

Pounds Lost: 20

The Big Hurdle: For Ziegler, it's all about the fourth and fifth months—that's when the whole program gets to be a chore and she loses motivation. This time, however, the contract came in handy.

Success: "Twenty pounds may not seem like a big deal to some people, but when you've had it to lose your whole adult life, it's a really big deal." The bonus is extra energy. "I'm an opera singer, and we're essentially athletes. I really needed this stamina onstage," she says.