"Dance Your Ass Off," which will air its first season finale on Monday (8/31), has proven a bona fide hit. Oxygen has expanded the finale show to 75 minutes, and has already added a reunion special for airing Sept. 7. Knowing what prompted creator/exec producer/show judge Lisa Ann Walter to come up with the series that combines dance and weight loss competition makes that success look all the sweeter.

The comedic actress and dancer put on pounds to co-star in the big-screen "Shall We Dance" with Richard Gere and Jennifer Lopez. When she went through a painful divorce, her weight increased still more.

"I have four kids -- and I was so depressed I couldn't get out of bed. I'd always been a little overweight, and in that relationship, I had help not liking myself," she recalls, choosing her words carefully.

"When I tried to take care of myself, I did it with chocolate or pot roast ... I knew I had to stop that cycle."

What helped her was dance. She spent time with dancer pals including pros Tony Dovolani and Karina Smirnoff, and she took salsa dance classes.

"It made me feel good I could be in dance class. If you stand tall like a dancer, you automatically look like you've lost 10 pounds."

Walter became fit, went back to work, and eventually hatched the idea of "DYAO." It took several years and a never-say-die push from Walter to get the show launched -- a hard-won victory.

Besides the show, she recently wrapped the big-screen "Five Killers" with Ashton Kutcher and Katherine Heigl.

And, in real life, "I have a cute young boyfriend who every day tells me how sexy and wonderful I am," she says of her film editor beau. "I'm enjoying myself."