Kelly Osbourne has opened up about her lack of fitness ability before she embarked on a healthier lifestyle.
The Fashion Police presenter admitted she could barely do ab exercises before she started working out.
“When I started exercising I couldn’t even do one sit-up! By the end of the first week I could do three, and that was a big deal,” she told Cosmopolitan Body magazine.
“Now I work out every day and I just don’t feel good if I miss it. It’s amazing how quickly your fitness builds, but you have to really want it.”
In one shot for the magazine, Kelly is seen in a brown and blue striped bikini sporting an enviable cleavage, toned arms and a slim upper torso.
But Kelly's body transformation is evident in the full-body shot, where she's wearing a ruffled pink bikini and showing off her toned stomach and muscular thighs.
The 23-year-old, who dropped five dress sizes on Dancing with the Stars in 2009, admits working out is a chore – but it’s worth it.
“Working out is not fun, I’m not going to lie and say it is. I sweat my arse off and I’m miserable for the hour I’m doing it but when I’m done, I feel amazing,” she revealed.
“There’s no quick fix and it does take a long time. It drives you mad when you see someone eating chips when you can’t have any, but it’s so worth it.”
But for Kelly, being healthy is a lifestyle change and she says done with fad diets.
“If you want to change your body you can’t just diet; if you do that, you lose weight, then get fat,” she said.
“You’ve got to commit to a whole life change and teach yourself a whole new lifestyle.
“It isn’t fun, but it never will be. I don’t deny myself anything – I still eat chocolate and cake and always will. Everything in moderation.”
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Full interview appears in new issue of Cosmopolitan Body, on sale Thursday 27 December 2012. Also available as a digital edition.