The Pussycat Dolls "sacrifice everything" to stay in shape.

Singer Kimberly Wyatt revealed the girls are forced to give up their favourite foods and exercise for hours to maintain their super-svelte figures.

She said: "The show is really tough on our bodies - we sacrifice everything. We have to take care of ourselves and we do that to the best of our ability.

"Epsom salts are very good for you, as are essential oils. I like a nice hot bubble bath to help my muscles relax."

Even their sexy stage costumes are punishing - they're often so tight the girls find it difficult to breathe.

Kimberly added: "There is certainly nothing comfortable about latex, but we are a performance group. Hopefully the costumes entertain our audience.

"Corsets are probably the hardest thing to perform in because you can hardly breathe."

The 27-year-old says the high-pressure environment and exhausting dance routines often lead to tension within the band.

"The relationships are amazing. But we are around each other a lot so communication can be tough. I don't take anything personally."