Christian Bale suffered a herniated disc after weight gain for film role

Christian Bale has been praised in the past for drastically changing his appearance to line up with his movie roles.

But that’s not to say changing his body for the purposes of a film comes without its own risks, as The Dark Knight actor has sustained injuries as a result of his physical transformations. Check out how he looked in American Hustle here:

Bale, who was around 39 years old at the time, gained 19kg for his role as the con artist Irving Rosenfeld in the movie.

However, director David O Russell admitted warning the actor to stop trying to transform himself for the role after he became injured.

Russell told USA Today in 2013: "At one point I said, ‘Enough already!’

“He lost three inches of height and even got a herniated disc. He's a quiet, sweet, smart person with endless passion. Women find him sexy in this movie, but it's all in the eyes."

Bale also admitted that as he’s growing older, he’s finding that the constant yo-yo weight differences for movie roles have taken a toll on his body.

He told the publication: “I think I'm certainly getting older. I thought I was going to lose the weight I gained for American Hustle. I said, two months, flat, that'll do it.

“It's almost six months later. Now I know that when I was in my early 20s it would have been two months and that's it."

Bale previously opened up about his drastic weight loss and differences in his sleep schedule for his role in The Machinist.

Even director Brad Anderson was 'stunned' at just how much weight the actor ended up losing for the role.

Bale explained: "I'd come off the back of making some films I'd been less than satisfied with and just really wanted something where I could become immersed and obsessed with it."