Jake Gyllenhaal: Fit freerunner
Jake Gyllenhaal got into shape to play an action hero in forthcoming summer flick Prince Of Persia: The Sands Of Time by freerunning.
The Donnie Darko star developed bulging biceps for the role of Prince Dastan after studying the French martial art Parkour, also known as freerunning.
Jake, 29, told People: "It got a little bit dicey there near the end, when they saw that I liked doing things that were dangerous - I tried my hand at things that were pushing it a little bit, there was this big 35 foot jump that I did that got a little hairy."
He said: "(I) never did anything this intensive (to change my body) before. It's a physical role. And when I commit to playing a part, it's 110 per cent.
"We worked really closely with David Belle, who invented Parkour. I worked with a lot of gymnasts. I started jumping off of a lot of things that were padded and learned the fundamental stuff, and then slowly started working on harder surfaces, really carefully.
"I'd say, 'OK, I'll try it,' and then I'd say, 'OH GOD, OH, please.' But then I'd get it, and we'd go a little further and a little longer and a little higher and just kept it up."
Jake plans to keep up the hobby now the movie has finished filming.
He said: "I enjoy being active as part of my daily insanity anyway, so I'll keep doing that."