Gwyneth Paltrow reshaped butt with exercise

Gwyneth Paltrow says the hardest part of her body to keep looking good is her butt.

The 'Country Strong' star works out almost every day to stay in shape, and when she first started getting serious about exercise and healthy eating her trainer Tracy Anderson told she needed to change her "square" derriere.

Revealing her problem, Gwyneth told the new issue of Self magazine: "My butt! My butt, butt, butt. 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.' The amazing thing is, she was right! And it's still changing!"

The 38-year-old actress - who has children Apple, six, and Moses, five, with her husband, Coldplay frontman Chris Martin - insists the secret to staying slim is finding a fitness and diet regime that works for you and can be maintained.

And Gwyneth is adamant it's important to allow yourself occasional indulgences otherwise you get bored.

The Oscar winner - who has just released her own cookbook 'My Father's Daughter: Delicious, Easy Recipes Celebrating Family & Togetherness' - explained: "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. 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.

"I say I always eat right, but the other night I had fried clams, pasta with duck sausage and two glasses of red wine. When I want to lose, I eat less pasta, bread and potatoes."