Gwyneth Paltrow Hired a Trainer to "Redesign" Her "Dumpy" Butt

Gwyneth Paltrow is in the best shape of her life -- but it didn't come easily.

"I never thought that I'd be considered to have a good body. I was bony up top and kind of dumpy on the bottom," Paltrow tells SELF's May issue. "But my trainer, Tracy Anderson, completely changed my legs, butt, arms and stomach. I feel better than ever, too."

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But don't be fooled: even Paltrow has problem areas.

"When Tracy met me, she said that I had a long, square butt that she was going to redesign, and I was, like, 'Yeah? Good luck,'" Paltrow recalls. "The amazing thing is, she was right! And it's still changing!"

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What's the secret to the Oscar winner's enviable bikini bod?

"I do 45 minutes of cardio five days a week, because I like to eat. I also try for 45 minutes of muscular structure work, which is toning, realigning and lengthening," Paltrow reveals. "If I'm prepping for something or I've been eating a lot of pie, I do two hours a day, six days a week for two weeks."

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That's not all. "I do Tracy's dance aerobics classes. It took me a long time to learn the choreography when I started. I was so uncoordinated!  After 11 minutes, I'd pass out and cry and say, 'I can't do this anymore!'" Paltrow, 38, says. "Now I can't live without it. You do it to loud music, and it's fun."

The My Father's Daughter author -- who curbs cravings by snacking on raw almonds with raisins -- has made exercise a priority for each member of her family, too.

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"Being active is part of our life. Moses is 5 now and Apple's turning 7, and they dance around with me. Apple is really into ballet and flamenco dancing now," Paltrow -- who married Coldplay's Chris Martin in 2003 -- tells the mag. "Taking care of yourself is being there for your kids, like how on a plane, they tell you to put on your oxygen mask first."