Supermodel Brinkley on what keeps her sexy!

She's 56, but still looks like a million dollars! Here's how one of the biggest names in fashion has held onto her youthful looks and a glimpse of her hottest, most celebrated magazine covers over the years.

Supermodel Christie Brinkley has shared her workout and fitness secrets with Shape magazine and she's also giving her advice on how anyone can look their best and stay fit with the same techniques.

She says that when it comes to working out, she finds variety is the key and that it's important for her not to get bored.

"I like to mix it up. I get bored if I do the same thing," the Daily Mail quoted her as saying.

"The only constant that I have in my life is that I start whatever I do with my Total Gym, because I believe it helps keep me from getting injured."

She added: "Think variety is the spice of sticking with an exercise routine, whether it's getting a dance tape one day, or getting a tape with those stretchy things for building resistance on a different day."

"Arm yourself with a few different things. Ask your friends to go jogging or on a long walk. Sign up for a dance class," she said.

Brinkley also loves to combine her love of the outdoors, especially water, with her work-out.

"Some of the things I like to do include kayaking, stand-up paddleboarding, sometimes surfing, sometimes rafting, running on the beach and walking down the beach waving my arms -- I call it swimming down the beach. Kind of silly-looking, but I don't care," she said.

Busy working mother Brinkley says she optimises every opportunity she can, even squeezing in some moves whilst cheering on her children's sports games from the sidelines.

"Parents were teasing me at the games last week. I was on the sidelines using a bench to do arm presses and then using it like a step board to step up and down," the model said.

And she even combines her workouts with her everyday chores like cleaning her teeth, or styling her hair.

"I thought, 'Okay, I''m going to multitask.' I''ll dry my hair as though I'm sitting on a chair, even though there's no chair there," she said.

"Then I'll do some squats; I'm always careful that my knee doesn't extend beyond my foot, so I don't put stress on my knees, but you can do so much for your upper legs while you're drying your hair."

"When I am brushing my teeth, I'm bending my leg behind me, or I'm lifting my leg up and holding it in that position so I'm squeezing my butt in."

"I can do that while I'm washing or slicing vegetables, too. Or I go up and down on my toes, working my calves a little bit."

"I also try to get in 100 push-ups every day. It's really easy. I keep a rolled up yoga mat under my bed. I throw it down and I'll do 30 push-ups before I get in the shower," she added.