Nicole Sullivan: How I Lost 35 Pounds of Baby Weight

Nicole Sullivan and Law & Order star Elisabeth Rohm are looking trimmer than ever -- but losing their baby weight didn't exactly happen overnight.

"I didn't know how to lose weight!" Sullivan, 40, recently admitted to UsMagazine.com. The comic -- who gave birth to her second son, Beckett, last August -- was trying to drop the 35 pounds she gained while pregnant.

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Determined to get her pre-baby body back, the King of Queens alum implemented a 1,200 calories per day diet via Jenny Craig.

"We just didn't eat vegetables before," Sullivan -- who ran her first 5K in June -- says of family meals. "And now we have vegetables every day."

The size 4 actress also got serious in the gym with Jenny Craig fitness consultant Christopher Ross, who coached Sullivan through strength training sessions twice a week.

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"Once you start working out, you want to eat better," Sullivan -- who also jogs 3 to 6 miles five days a week -- tells Us. "Then you're like, Is that burger really worth it?"

Rohm, however, tells Us she had a more difficult time losing the 70 pounds she gained in 2008 while pregnant with daughter Easton, 2.

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"Six months after, I was still wearing maternity clothes," the actress, 37, confesses.

According to Rohm, it took her nearly a year to get her size 6 body back.

How'd she do it? She began running for 45 minutes six days a week and cut sugar and dairy from her diet.

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"It's exhilarating," she says of her new lifestyle. "I've really changed!"

But Rohm, who now co-owns Circuit Works in L.A. (where she trains four days a week) tells Us she never felt pressure to slim down quickly.

"There are all different shapes and sizes of beauty," she says.