After giving birth to twins Dolly and Charlie in December 2008, Rebecca Romijn was determined to get her pre-baby body back. Unfortunately, it turned out to be a much bigger challenge than she had anticipated.
"Losing that weight was probably the hardest thing I've ever done in my life," Romijn, 39, 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."
A friend convinced Romijn to try Bikram yoga, which she credits with helping her shed more than 60 pounds.
"At first, the idea of doing a 90-minute workout in a 105-degree room sounded like torture," Romijn admits. "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!"
Dieting was another problem for the Sports Illustrated supermodel. The 5-foot-11 star "forgot how much I was supposed to eat to keep my weight in check" while she was both pregnant and nursing.
"I went on a major diet about eight months ago. I cut out starch, dairy, fat, red meat, alcohol and sugar," Romijn tells Fitness. "Just being on a diet was weird for me. I had never been on one in my life, and suddenly I was counting calories and measuring my food. Cutting out sugar was definitely the hardest. The first week I thought I was going to die. The cravings were bad. But after that, it was easy."
Romijn's husband, Jerry O'Connell, helps her find new ways to stay in shape, too
"We love to take long bike rides. We have a tandem bike, and we go up in the hills near our home," she says of O'Connell, 37. "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."