Natalie Portman likes "extreme experiences" and her favourite hobby is "scuba-diving".

The actress - who plays sexually repressed ballerina Nina in new movie 'Black Swan' - enjoys activities that get her pulse racing but admits there are plenty of things she is too scared to do.

She told Empire magazine: "I have fears, I'm afraid of a lot. I am not a danger seeker but I do like extreme experiences. But not ones that I feel would threaten my life. I like scuba-diving, for Example, but I wouldn't free-dive."

Natalie takes her adrenalin addiction into her working life and she tries to take on roles which frighten and push her creatively.

She added: "Work-wise, I try to do things that scare me, because I know they're going to challenge me. But I didn't know what I was in for with 'Black Swan'. I didn't realise what it was going to be like. But the cliche is true, the more you put in, the more you get out."

In 'Black Swan' Natalie's character awakens her sexual urges when she auditions for the roles of the Swan Queen and the Black Swan in 'Swan Lake' in the film and onscreen the 29-year-old actress is seen masturbating and indulging in a lesbian romp.

But Natalie insists she was never fazed by what director Darren Aronofsky asked her to do.

She said: "Everything that scared me about the role was also what drew me to it. It was an amazing opportunity to challenge myself emotionally and physically."