Amanda Seyfried has to work hard to stay slim.

The 'Mamma Mia!' actress claims her enviable figure is the result of gruelling exercise and she has even hired a personal trainer across the Atlantic to make sure she works out wherever she goes.

The American beauty told Tatler magazine: ''One minute on the VersaClimber is all I can manage. I have to work hard to keep trim, so in London, I exercise with Dalton Wong at Twenty Two Training - he really pushes you to your limit.''

The 27-year-old blonde says her biggest weakness when it comes to make-up is nail polish and she has amassed a huge collection of her favourite nude shades over the years.

Amanda said: ''I have about fifty nail polishes. Weirdly, I only ever wear nude. Givenchy's Le Vernis in Beige Mousseline is beautiful.''

However, the star is low maintenance most of the time and only ever visits the salon to get her legs waxed.

She quipped: ''Every two weeks I get my legs waxed. It's basically the only maintenance I do.''

Self-declared tomboy Amanda also never leaves the house without a splash of scent to make her feel more elegant.

She said: ''One squirt of Givenchy Very Irresistible and I'm set for the day. I'm a tomboy, so this makes me feel much more feminine.''