Chris Hemsworth had to "force feed" himself to get in shape for 'Thor'.

The actor plays the titular role in the new movie but had to bulk up to portray the superhero and while he was fine with working out, he admits his diet was tough.

He said: "The most uncomfortable thing was the eating. I didn't mind the working out. I'd never really lifted weights to that capacity beforehand, and it was certainly a whole new education for a good six months. And, I just don't naturally sit at that weight, so I had to force feed myself with 20 chicken breasts, rice, steak and very boring, plain things. The most exhausting part of the whole film was the eating. It wasn't fun stuff either. It wasn't hamburgers and pizza, and what have you."

As well as getting into the role physically, Chris also made sure he was familiar with the character by reading lots of comic books.

He told Collider.com "I started with the comic books. I didn't read all of them - there are 40 or 50 years worth - but I certainly read enough to get a sense of who he was and the world he was from. And then, I read some things on Norse mythology and the fatalistic view they have, that everything is pre-ordained. That would lead the Vikings into a fearless attitude in battle and with their lives. They would certainly back their opinions and they were not swayed easily. That spoke volumes to me about the character."