8 actors who transformed their bodies for roles

From bulging muscles to skin and bones, the physical metamorphosis of Hollywood stars is an art all its own.

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Hilary Swank in "Million Dollar Baby" Hilary Swank in "Million Dollar Baby" (Photo: Million Dollar Baby)

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Hilary Swank for 'Million Dollar Baby'

What's remarkable about American actress's Hilary Swank's body transformation for "Million Dollar Baby" is that she managed to pull off the physicality of a female boxer in only 90 days.

The grueling three-month regimen included four- to six-hour daily workouts of boxing and weightlifting, as well as a meal plan that had the actress eating every 90 minutes. To achieve her goal, Swank said she needed to break through mental barriers. "I found more than anything that what I really learned from this movie was the power of the mind and how my mind was my biggest obstacle," she told MovieWeb.

While producers had requested she put on 10 pounds of muscle, Swank's dedication to her training surprised everyone with 19 pounds added to her frame. The role earned her a second Oscar at the 77th Academy Awards.

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