She's looking toned in her striped bikini on the cover of Allure magazine's July 2009 issue, but Fergie revealed getting back her beach-perfect body after filming Rob Marshall's "Nine" wasn't very easy.
Last year, the Black Eyed Peas singer was asked to gain weight by the director in order to play the part of Saraghina, a prostitute in "Nine," which is due to hit movie theaters in November. And Fergie happily indulged every craving, alongside co-star Penelope Cruz, eventually gaining 17 pounds for the role on her petite frame.
The two ordered "everything fried and full of fat and salty" while filming in London.
"We were eating our brains out," Fergie told Allure.
But taking the weight off wasn't something a woman known for her washboard abs found easy to do.
"It was a very gradual thing getting back into it and finally letting a trainer train me," she said. "I didn't want to be told what to do, and I wasn't mentally ready to crack the whip."
Fergie revealed she eventually turned to husband Josh Duhamel's trainer and she now stays in shape by jumping rope, taking outdoor hikes and weight lifting. And of course, mid-section exercises.
"If I don't do sit-ups, my stomach sticks out," she told the mag. "Legs are easy for me. That's my lucky spot."
But while the singer is in fine form in her Allure spread, Fergie revealed she has undergone a big change in her life.
"I'm not just going to be the booty-shake girl," she said.
Among those changes was dying her blonde locks a dark shade of brown in the run up to promote her new album with the Black Eyed Peas – "The E.N.D."
"Something inside of me said, 'I need an evolution,'" Fergie revealed. "I'm in a new phase of life. I'm married; I have a new album. It felt time."
But while change is important, Fergie said she also has discipline in her life – her very scheduled on-the-road beauty regime.
"I need structure. I need to get enough sleep. I need to make sure that I'm having regular workouts, and that they put in time for hair and makeup and nails, because I do have to get my nails done," the pop star noted. "I have to get my roots touched up and get facials, because when you're traveling, the skin doesn't look as nice."
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