Jake Gyllenhaal expects to get fat soon.

The actor has stunned fans with his toned physique after working out in preparation for his role in 'Prince of Persia: The Sands of Time' - but has warned his supporters that his new shape won't last long because it was so difficult to achieve.

He said: "I probably put on five pounds of muscle which wasn't easy. It might look good in the movie but it's probably going to turn to fat before long.

"I'm going to be fat but I'm going to be happy."

Jake, 29, recently revealed he is excited about seeing action figure replicas of himself, which will be released around the same time as the action adventure movie.

He said: "A lot of people find it weird to have little action figures of themselves, but I think it's great.

"In fact it's awesome! I can't wait. I'm going to buy loads."