Ever wonder how Hollywood actors transform their bodies so quickly for big roles? Try a 6,000 calorie-a-day diet.

That's exactly the kind of hardcore training Hugh Jackman is putting himself through as he prepares to film "The Wolverine." The fifth film in which the Australian actor is portraying the wildly popular Marvel Comics character, the movie is being directed by "Black Swan" helmer Darren Aronofsky. Known for his visceral style of filmmaking, Aronofsky wants the flick to better capture the Wolverine that fans know from the comics. For Jackman, this means reshaping his lean 6'3", 190-pound frame with an intense diet to better reflect the short, stocky cartoon wildman.

"It's 6,000 calories a day," the actor told the LA Times. "It's rough."

Jackman went on to say he's currently at 210 and continues to gain. Look for the results of his hard work when "The Wolverine" hits screens in 2012.

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