Gwyneth Paltrow may be the most beautiful woman in the world, according to People magazine. But winning that title wasn’t easy for the 40-year-old Iron Man actress. The mother of Apple, 8, and Moses, 7, had to work to get her body back after having two children. And it took continued, disciplined work, says trainer Tracy Anderson.

"Gwyneth had extra weight she couldn't drop from her pregnancy with Moses, and she needed to get in shape for her first action film, Iron Man,” Anderson explained about the 5-foot-9 actress.

So how did Anderson motivate Paltrow to hit the gym daily? "With my daughter it had been easier, but this time, no matter what I did, I felt stuck,” Paltrow explained to Redbook recalling her first meeting with Anderson. “I couldn't shift the weight. But I met Tracy and she was this force from the second I met her. She pulled my pants off. I'll never forget it. She was like, 'Oh, my God, wow, I just am so surprised, because you look so good in clothes. I wasn't expecting this.'"

Anderson’s blunt criticism of Paltrow’s body may seem harsh, but it was reportedly the push Paltrow needed to get her body back into shape. "She hid her problem areas so well before me that I'm like, ‘I really wish your naked butt was everywhere before me and after me,’” Anderson said

Gwyneth Paltrow If we had a toned body like Gwyneth Paltrow we would be showing off our figure in a sheer dress, too!

"It's so important to incorporate fitness into your life. You have to make it so it's like brushing your teeth - just something you do every day," she told Company magazine. "If you get up 45 minutes earlier, you can run for half an hour or just stick in a fitness DVD."

But it wasn't all about cardio and strength training. Paltrow completely transformed her diet. "Well, I'm on a cleanse right now!” Paltrow continued to elaborate. “I'm doing the Cleanse Program, which is a 21-day thing. I'm on day ten, so I'm nearly half way there.”

Paltrow even put her family on a carb-free diet! “Sometimes when my family is not eating pasta, bread or processed grains like white rice, we’re left with that specific hunger that comes with avoiding carbs,” the Daily Mail reported.

Paltrow’s willpower has almost become legendary. “I'm a very disciplined person so when I commit to something, I never waiver," she said. "I have crazy self-discipline."