Ali Larter: 'I Gained 45 Lbs'
PHOTO: Ali Larter visits the SiriusXM Studios, Aug. 15, 2013 in New York City.

(Photo Credit: Cindy Ord/Getty Images)

After the effort it took to lose 45 lbs. gained from having son Theodore in 2010, Ali Larter said it's hard to impress her "with a body that hasn't had a baby."

The "Heroes" actress, 37, spoke with Health for its September issue and admitted that it took five months of working out "a lot" and "doing a food delivery service" to cut the weight.

"I tend to work out for an hour about four days a week, and I love to run," she told Health. "It's the quickest way, with my busy schedule, to be able to enjoy my life and keep my weight at where I want it to be. Sometimes I grab a trashy magazine and hit the treadmill."

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Larter is not opposed to trying new workouts to keep her body guessing, especially since she has "to eat dessert every day."

"I filmed a movie last year called 'Lovesick ,' and I played a ballet teacher," she said. "I took 10 ballet lessons, and I loved it. My body really responded to it, so I have been taking barre classes."

For those who think baby weight is something that disappears overnight, Larter said it's not that simple.

"Have a baby and then let's talk," she said.

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