Elle Fanning has revealed she struggled growing up as a child star on set.

The 19-year-old actress - who is the younger sister of Hollywood star Dakota Fanning - made her movie debut in the 2001 drama 'I Am Sam' and has since gone on to forge an impressing career on screen.

Elle has now opened up about how behind the scenes she was struggling to cope with the challenges of adolescence.

She said: ''When I was 12, I grew seven inches in a year. And it hurt every day. On 'Somewhere' (Sofia Coppola's 2010 drama) I grew two shoe sizes during filming. And I would pass out a lot because I hadn't grown into my body. So that wasn't a great time. It definitely wasn't painless.''

But now she's coming to the end of her teens, Elle has dealt with all various problems of puberty and now wants to push on in her career and she compares her drive to succeed to being similar to a top sportswoman.

She explained: ''It's in my blood; I can't help it. Actors and athletes are similar, I think. You set a goal for yourself; you're ready for a challenge. You prepare for the match or you're getting ready for the role. The adrenaline when you have a big scene to do is huge.''

Elle - who will next be seen in 'The Beguiled' - believes her performance in 2012 movie 'Ginger & Rosa' about teenage friends coming of age was pivotal in shaping her into the actress she is today.

She said: ''When I did 'Ginger & Rosa' when I was 13, that's maybe the role that signified the most for me, because I grew as an actress on that film and I felt much older at the end of it. I had a British accent in it. I dyed my hair red, when I had always been blonde, and so I didn't feel like myself at all. Something clicked. I thought, 'Oh this is what acting is supposed to feel like.''