Kit Harington has revealed that filming Pompeii has been the most challenging role of his career.
The Game Of Thrones actor, who stars as a slave-turned-gladiator in Paul WS Anderson's Roman epic, admitted that his first leading big-screen role has been taking its toll on him.
"It's the first time I've really experienced something like this, because Game Of Thrones, it's very kind of sporadic filming. This is the first time I've been a lead role in a movie, and it is demanding, it's tiring," the 26-year-old told Collider.
"There's a lot of fighting in this, and there's a lot of stunts. I'm in the best shape I've ever been, but I'm exhausted. I think I'll get ill after this, I think I'll have to relax. But it's great, I mean, I love being busy."
Kit has been pumping iron and is on a special diet to get into shape for the role.
"It's an action film, where I've got my arms out the whole time, so I have to try and look tough," he explained. "And I'm next to all these stunt boys who are huge, so I need to kind of compete with them, so it doesn't look ridiculous that I'm beating them up."
The British actor, who plays Jon Snow in the fantasy series Game Of Thrones, said he has thrown himself into the action sequences.
"I love action. I love doing fight scenes, I always have. I've sort of found myself in a kind of period niche," he said.
"What grabbed me about this one was I just wanted to throw a sword about. And I thought it was quite an exciting script."
Pompeii, which also stars Kiefer Sutherland and Emily Browning, will be out in 2014.