Kelly Osbourne thinks she could be addicted to exercise.

The reality TV star - who has shed over 40lbs in the past year - always ensures she accompanies her 20-year-old fiance Luke Worrall to the gym, even if she doesn't feel well, because she worries she won't see a difference if she misses a session.

She said: "I like to go to the gym three times a week with Luke - even when I'm not feeling great. It almost feels like I'm sweating out the rubbish! We go to the gym together, but we don't work out together - I work out with my trainer.

"I do Power Plates and cardio work, and he gets in shape with weights. I think I'm reaching that addictive stage of working out, where I know if I just put in an hour, I'll feel the difference. I'm not at the point where I can be bothered putting in two hours though!"

The 23-year-old star also credits her appearance on US TV talent show 'Dancing With The Stars' for overhauling her meal plans as she is now more aware of what is good for her.

She added in her column for Closer magazine: "I've completely changed the way I eat since doing 'Dancing with the Stars'."

Kelly has previously spoken about how Pilates in particular has helped her to stay in shape.

She said: "Pilates is amazing, my posture is so much better and I'm even starting to get muscles on my tummy - it's incredible."