Million dollar body

When Hilary Swank took the part of a boxing heroine in Clint Eastwood's Million Dollar Baby, she underwent a gruelling training regime.

The tiny-framed 30-year-old piled on almost 20lb in muscle - and wolfed down 4,000 calories per day.

But unlike most Hollywood actresses, who ditch the excess weight as soon as their roles are over, Swank is keeping her pumped-up physique.

In this picture, for Vanity Fair, she shows off both her meticulously honed frame and her new strength and agility.

Swank, who has been nominated for an Oscar for her role as prize-fighter

Maggie Fitzgerald, trained for five hours a day over three months and went on a high-protein, low-carb diet.

She says: "I knew that, if I was playing a boxer, I'd better look like one. The first time I hit somebody, I said, I'm sorry, and my trainer just about threw me out of the gym. "As I learned more about boxing I began to see it like a great chess game. You are one with your opponent and there's nothing else that you're thinking about except their strength and their weakness and, at the same time, you're learning about your own."

Her diet was just as tough: "There was a point where I could only eat 50 grams of carbs a day. It was challenging to stay on that really strict diet, but it helped me to bulk up. They wanted me to put on 10lbs of muscle, and I added 19."

So extreme was the training schedule that she developed a blood infection from a huge blister on her foot.

"I couldn't believe the pain," recalls Swank. "The doctor said, 'This is really serious. If you had waited two more hours, you would have been in the hospital for three weeks. And if it gets to your heart, that's it'."

Shooting the film led to a few reallife knocks. "Clint doesn't believe in rehearsal or choreography. when I found out, I felt a little nervous. But that's why Clint Eastwood is the best.