Jake Gyllenhaal vigorously rubs his body with soap in a bid to show off his muscles.

The handsome actor had to bulk up for his role as Prince Dastan in new movie 'Prince of Persia: The Sands of Time' and says he had to work hard at his appearance, which included growing his hair long.

He quipped: "The Jake Gyllenhaal work out plan...starts with growing long, long hair. Very long - gorgeous greasy locks and then washing every day..Wash, shampoo, then condition. Washing works the biceps and then the triceps by conditioning. And vigorously rubbing all of your body with soap really defines the abs and the pectoral muscles. And if you do squats while you're bathing - that's it!"

Jake took his training seriously because he wanted to be able to give his best performance in the film.

He said: "It was really important for me to be able to do all the stunts and the things asked of me."

However, he admits he has neglected his training in recent months following the completion of filming.

Jake - who has now gone back to his short-haired look - told TV show 'Entertainment Tonight Canada': "I don't have any muscles anymore now. It's all just whittled down to little twigs. I walk around unable to move my arms."