Nadine Coyle's legs are so skinny she is unable to run.
The Girls Aloud singer - who is a UK size 6 to 8 and has been criticised in the past for her slim frame - struggled to keep up with her bandmates when they used to exercise together, according to Kimberley Walsh.
She told Zest magazine: "Some days, we'd all work out together. It was very amusing. Nadine can't run at all. Her legs are so thin, all she does is say: `It hurts. It hurts to run.'"
While Kimberley would love to lose weight, she admitted she doesn't have the willpower and says she has learned to be happy with her "normal" figure.
She explained in the new issue of Zest magazine: "I know I could be thinner but then I couldn't eat much and I love chocolate cakes and biscuits with a cup of tea. No matter what diet I'm on, I'll never turn down chocolate. It's my guilty pleasure.
"I hate the word 'normal' but that's what I am. Not fat. Not thin. I have a bit of cellulite - every woman in this country does - small or big. If women look at me and then feel a bit more comfortable about their own bodies, I think it's a positive thing. I want girls to know you can look attractive whatever your shape."