But the supermodel is determined to get fighting fit once more and she's using a photo of herself as her goal!
Christie - who will ring in her 67th birthday in February - looked incredible in a workout snap she shared on Instagram and when fans marvelled at her appearance, she admitted it wasn't a new image.
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Wearing hot pink leggings and a white, tight top, Christie showcased her tiny waist and toned legs, and one follower said: "Happy New Year, Christie! You are more beautiful with each passing year."
Christie then admitted: "I'm now looking at this picture from a few months ago as goals. I may have put on a little weight over the quarantine….that's why it's in my bedroom now… total gym to the rescue."
The star posted the photos to promote the gym equipment, which she's been a fan of for 20 years.
Christie is using her own photo as a fitness goal
She proudly stood alongside the equipment with a huge smile on her face and actress Olivia Munn branded her "the prettiest," while her non-famous fans said: "Way to go Christie and show us you still got it."
Christie previously discussed her small weight gain to Extra TV and said: "I did put on a couple of pounds. So I dragged my Total Gym into my bedroom.
"Getting out and gardening is a lot of work…We'll take the boat to a deserted beach and we'll do speed walks or running.
"I'm determined to get back to my fighting shape."
Christie has been in lockdown with her family
Christie is embracing the ageing process and has said she has more confidence the older she gets.
"Around 50, you start letting yourself off the hook, and you have a real awareness of priorities and what really matters," she told Us Weekly.
"Others' opinions just don’t have power over you anymore. The only opinions that really matter to you are those of the people you love."
She added: "Aging is inevitable. If I'm lucky, I'm going to be running around as an older woman with my hard-earned wrinkles. It's inevitable."
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