Natalie Portman didn't have any time to herself while filming 'Black Swan'.

The Hollywood beauty - who won the Golden Globe for Best Actress thanks to her performance as ballet dancer Nina in the Darren Aronofsky-directed project - couldn't switch off from her character because of the amount she had to work out to be at her physical peak while shooting.

She told BANG Showbiz: "It was challenging, you know, I like to shut off the character as soon as I'd finished, whether that's finishing a take or going home for the day. It was really difficult because I had so much training outside of work to do.

"When work was done then I had to go to the gym, and then I had to get up at 5am and workout before. There wasn't really any time to just relax and be myself."

Work on the project - on which she met now-fiance child Benjamin Milipied - was made even tougher as she often found herself unable to balance the demands of physicality with emotion, often concentrating so much she would have her tongue "hanging out".

She laughed: "Balancing the physical with the emotional because sometimes just to do a certain move you need so much concentration, my mouth would be hanging open and I'd have a concentration face, it'd be all furrowed.

"Half the time they were trying just trying to get me to not have my tongue sticking out. And then to add on to that I have to be acting!"