LOS ANGELES - Christian Bale's work in "The Fighter" as the drug-using, ex-boxer Dicky Eklund is the latest example of how the actor transforms himself for a role.

It can be as subtle as the deep-throated growls of Batman in "The Dark Knight" or as obvious as the massive amount of weight he lost for "The Machinist." For Bale, taking on a role is a process of building the character that changes each time.

"I really don't have a system," Bale said. "No matter where it starts, with each little bit I hope that it will meet at one point later on. I always start with 'Christ, how am I going to do this?' I always forget how hard it is to go through the kind of birthing pains of putting a character together."

To play Eklund, Bale traded his normal Welsh accent for a Boston brogue, shaved in a bald spot and lost enough weight to look like a cocaine addict.

Because "The Fighter" is based on the true story of boxing champ Micky Ward and his self-destructive brother, Bale was able to use the real Eklund as a pattern. The only problem: Bale found Eklund to be such a character, he actually had to underplay the role.

"Dicky's got his own thing going on. He calls it Dickynese. I really had to tone down his natural rhythm and voice because I understand him completely now because my ear's with it. But, if I had done it exactly like Dicky, we would have needed subtitles," Bale said. "With Dicky there was so much going on, including a fused spine that dictates a lot of his body language. It was all one big thing that I had to break down - brick by brick - to be able to play him."

The easiest part of playing the role was relating to the boxing world because it's so similar to acting. Both feature hopefuls who have to work their way to the top through a series of hits and misses. And in both, it's not always the best contenders who get the big opportunities.

"You have all the people behind who are pulling the strings. Another guy may deserve a chance more, but he might not have the right representation and another guy steps in and gets it. In that manner, acting and boxing are very similar," Bale said.

After filming "The Fighter," Bale took a break. He looks completely different with his long hair and beard, both grown because he hasn't been working. He'll soon begin his next transformation for work on "The Dark Knight Rises."

Rumors are rampant about what director Christopher Nolan has in mind for the next film in the Batman series, which is scheduled to be released in 2012.

"I have no idea which of the rumors are real," Bale said. "All I know is that Chris will tell me what I need to know when we start filming."