Paulina Porizkova, 56, Runs on the Beach in a Bikini—Despite Having 'Some Arthritis' in Her Hips

Paulina Porizkova is living out her beach fantasy—and grinning wide as she does it.

On Saturday, the 56-year-old model posted a video of herself to Instagram that shows her wearing a blue string bikini, with beach-tousled hair, running through the ocean water.

"Here's my Baywatch moment! Always wanted to do this in slow-mo, but I thought instead I post the real version, me TRYING to look like a Baywatch babe," she wrote in the caption. And yes, the background music is of course the Baywatch theme song.

She ended the post with a few playful hashtags—some of which alluded to her age—including #betweenjloandbettywhite, #nomakeup, #100percentreal, and #sexyhasnoexpirationdate.

The comment section was a space for celebration and positive vibes. "Girl, you're sexy even snoring😂😍," one person wrote. "You've still got it 🙌," someone else said. "You are AMAZING! I enjoy seeing you run this way...you look so free, full of joy, kind of contagious...way to go!!!👏," another person commented.

Even though running on the beach like a Baywatch lifeguard is something she's always wanted to do, it turns out that she's actually not a huge fan of running. "It's no secret to my friends that I hate running," she wrote in the caption. "I have some arthritis in my hips ( so much for having the body of a thirty year old) and running isn't exactly comfortable. Also, I need to run for a reason, like AWAY from a bear or TO a great sample sale.😜"

And just FYI, Porizkova is definitely not alone when it comes to having arthritis in the hips. Millions of women experience it, with inflammatory arthritis like rheumatoid arthritis, ankylosing spondylitis, and systemic lupus erythematosus being possible causes. But the most common cause of arthritis in the hips is osteoarthritis, according to the American Academy of Orthopaedic Surgeons. Known as the "wear-and-tear" arthritis, osteoarthritis damages cartilage over time, which can cause symptoms like stiffness, tenderness, and loss of flexibility after you reach middle age. If you have osteoarthritis of the hip, you might also experience pain in your hip during or after movement, according to the Mayo Clinic.

So instead of running, Porizkova chooses other forms of exercise, like Pilates. "At fifty-six, staying in shape takes work! I try to exercise at least 3-5 days a week," she wrote on Instagram in June, to go along a video of her working out her abs, glutes, and obliques during a Pilates class.

Her Baywatch-inspired beach bikini video was the latest in a series of posts that she had uploaded while on vacation in Costa Rica. In one video she posted, she was standing under a waterfall. Other posts have been snapshots of her posing poolside and on the beach—all of the posts of her in different string bikinis.

"I have come here to heal repeatedly. I don't know what it is about being here, but my anxiety drops to nearly undetectable, and I feel like I get to pause all the stress of life," she had said in a post about her vacation spot last week. And now that her vacation has ended, she said in a post on Sunday that she feels "restored and hopeful."