Hollywood star Rachel McAdams has revealed her training to play a boxer's wife in her new film also informed her role in hit TV crime drama True Detective.

The actress, who is best known for her roles in Mean Girls, The Notebook and About Time, stepped into the ring herself in preparation for her role as Maureen Hope in Southpaw.

McAdams, 36, plays the wife of boxer Billy Hope - portrayed by Jake Gyllenhaal - in a film that looks at how he gets his life back on track after he suffers a tragedy.

Gyllenhaal trained for hours every day to prepare for the role but McAdams also threw her fair share of punches. The workout also helped prepare her to depict a detective at odds with the system she serves in the second series of gritty crime thriller True Detective.

McAdams plays sheriff's detective Ani Bezzerides in the show, which also stars Colin Farrell and Vince Vaughn.

Walking the red carpet at the New York premiere of Southpaw dressed in a black dress with a cut-out panel on the midriff, McAdams said: "It definitely helped me get into the mindset of my own character because I figured she would make it her business to know everything about boxing in the ring and outside it.

"It was a great workout for True Detective because I figure that character has boxed in her life so it carried over into that."

The actress said she was immediately haunted by the role of Maureen Hope after she read the Southpaw script and she now hopes the character stays with audiences too.

"It doesn't always happen this way but it is great when you finish a script and you can't stop thinking about that character and they are coming everywhere with you and you go to sleep and dream about them. It's a good sign when I can't get them out of my head."

Asked if she thinks audiences will feel this way too, she said: "I don't know, I hope so, you always hope your work has some impact but it will definitely stay with me for a long time."

Southpaw is released in UK cinemas on Friday.

The second season of True Detective airs on Sky Atlantic on Wednesdays.