Rebecca Romijn: How I Lost 60 Pounds of Baby Weight

Regaining your figure after giving birth is hard enough, but it's even more of a challenge if you carried twins -- and that's exactly what Rebecca Romijn was faced with after the December 2008 birth of daughters Dolly and Charlie. As a supermodel for over two decades, Romijn had never even dieted a day in her life, but after gaining 60 pounds during her pregnancy, the 39-year-old had to rethink her entire fitness routine -- and learn how to eat healthy. "Losing that weight was probably the hardest thing I've ever done in my life," Romijn tells the March issue of Fitness. "Everything I did before I got pregnant -- like Pilates, which I had done for about 14 years -- didn't work anymore. I had to change the way I worked out, the way I ate -- everything."

What did work for Romijn was cutting out starch, dairy, red meat, alcohol, and sugar, as well as Bikram yoga -- which involves sweating it out in a 105-degree room for 90 minutes while holding a variety of 26 poses -- three days a week. The idea, suggested to her by a friend, "sounded like torture," she jokes. "But the sweating is exactly what I became addicted to. My body changed dramatically almost immediately. I'm stronger, I have more energy and I feel better, too. I was proud to get back into a bikini!"

Still, don't expect to see Romijn -- who wore only blue body paint for her role as Mystique in 2000's "X-Men" -- to flaunt her post-baby body in the buff any time soon. Although Playboy has asked her numerous times to grace its cover, the mom thinks it would send the wrong message to her daughters. "I don't want to dis the magazine or the beautiful women in it -- some of whom are my friends -- but I would never do it. And now that I'm a mom of two girls, I definitely would never go that route."

Instead, husband Jerry O'Connell has been the beneficiary of all of his wife's hard work, although he likes her with a little more meat on her bones. "Every meal with Jerry includes wine and dessert, which I love," says Romijn. "Before we had kids, I gained weight from eating like that. But I was happy and in love, and my clothes still fit. Jerry liked how I looked. He's very much a 'there's more to hold on to' kind of guy."

The actor even breaks a sweat with his wife from time to time -- although it has created a friendly rivalry between the two. "We love to take long bike rides. We have a tandem bike, and we go up in the hills near our home. Jerry is very show-offy when he's good at something, and he's pretty much good at everything. But he's been doing Bikram yoga for about a year now, and he isn't very flexible. I'm happy there's one thing I'm better at than he is."

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