Christian Bale is no stranger to extreme weight loss. The Batman star, who lost weight to play a former boxer addicted to crack in The Fighter, said he shed his pounds by running.

"[I] was just running like crazy. I could run four hours on and I felt really healthy," Bale told Latino Review. He also joked, "Oh I do a lot of coke whenever I lose weight," but later added the clarification, "I'm not sure if it's so funny for this movie, to say that."

Though Bale, who lost over 60 pounds for his role in The Machinist before gaining all of it back and then some to play the Caped Crusader, had to once again lose weight for this role, co-star Mark Wahlberg had to bulk up to play boxer "Irish" Mickey Ward.

"The movie was a go then it fell apart and I just continued to train," he said. "So after four and a half, well, three and a half years, I felt confident enough to go in there and be believable as a boxer who could possibly win the welterweight title."

But after shooting ended, Wahlberg abandoned his routine in the ring. "As far as the regimen, my new regimen consists of a bottle of red wine and a lot of food," Wahlberg told the site. "And I'm enjoying myself, but my wife is like, you know, 'You – you're starting to look really bad.'"

The Fighter opens on December 10. —ISHITA SINGH

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