The Australian actor has played the `X-Men` character four times in previous movies, and he reveals the Oscar-nominated director wants him to put on more bulk than he did in the last film `X Men Origins: Wolverine`.
He said: "It`s 6,000 calories a day. It`s rough. Right now, I`m 210 lbs.
"Darren said with the last one, `Hey, you looked great, but you`re so tall that in those long shots you looked kind of like Clint Eastwood, and that`s not Wolverine.`
He said that Wolverine, in the comics, is powerful, stocky. He`s short and thick. So he said, `I want you to go there, get bigger.` "
Darren is well known for asking a lot of the actors in his films - his latest movie `Black Swan` saw star Natalie Portman at her thinnest to portray psychologically-troubled ballet dancer Nina.
`The Wolverine` - written by Christopher McQuarrie (The Tourist) - is expected for release in 2012.