Gwyneth Paltrow has been "hibernating" since she turned 30.

The 36-year-old star - who has four-year-old daughter Apple and son Moses, two, with her husband Chris Martin - felt so over-exposed she withdrew from Hollywood to focus on her private life.

She said: "I was definitely hibernating for a while and I do feel that now I am kind of getting back into the world.

"But a lot has changed in my life and it's very nice to come back to work.

"I was happy in my sweat pants being a mother and I honestly didn't know if the fire would come back. Then when my son was about six months old I started to feel like the artist was coming out of hibernation. That's when Jon Favreau called me about 'Iron Man'."

When Gwyneth won the Best Actress Oscar in 1998 for her performance in 'Shakespeare in Love' she was inundated with roles and was left exhausted.

She told Total Film magazine: "I didn't realise I could say no, it was like somebody shot a gun and I just kept running until I completely lost the desire to work."