Theo James relies on boxing to help him stay trim.
The 29-year-old actor stars as Four in Divergent, which is set in a world split into groups. The character had to look beefy, meaning Theo spent hours in the gym in preparation.
"I wanted Four to be quite muscly, so I had to hit it pretty hard and the director said I had to be much broader. I like to do a bit of boxing, which means you don't end up being a fat b*****d," he laughed to British magazine Heat.
Theo had to flash his muscles in the movie and his character is also covered in tattoos. It's led to claims the movie will win him hordes of female admirers, although he prefers not to think about that too much.
"Me imagining myself as a sex symbol is quite funny," he explained. "It's tricky when you have to take your top off in a film because everyone is going to want to see that stuff. I guess with those scenes it's kind of functional; at least he's physically showing her something. He's not just like, 'Look at my arse.'"
Divergent is based on the first of a series of three young adult books by Veronica Roth and has drawn parallels with The Hunger Games and Twilight. Theo doesn't expect to be as catapulted into the limelight as Robert Pattinson was when he took on the role of Twilight's Edward Cullen though.
"With the Robert Pattinson thing, that was very specific. It captured this kind of Gothic, cultural explosion, and I'm not sure it's something that just happens," he claimed.
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