Mike Tindall Dives into 2023 (Wearing Another Tiny Swim Suit!) for a Special Cause

Mike Tindall/Instagram

Mike Tindall braved the January cold for an important charitable cause.

On Monday, the 44-year-old retired rugby player posted a video of himself participating in a polar plunge for Doddie Aid, an annual six-week challenge encouraging physical activity to fundraise for research for a cure for Motor Neuron Disease (MND). Doddie Aid is organized by the My Name'5 Doddie Foundation, established by Scottish rugby player Doddie Weir, who died in November 2022 after being diagnosed with MND.

"Happy new year everyone, the first of January. It's not that cold, it's a little bit cold. We're down here at the lake, and it's time for the Doddie Dunk," Queen Elizabeth's grandson-in-law began, slowly unzipping his jacket to reveal swim briefs.

"And so, it's that time. Sorry, it's very nipply out here," he joked, hands to his chest. "Should we go in?" he asked, wading into a small pond behind two friends, and gracefully diving under.

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After returning to the surface, the men playfully yelled about the cold water. The clip closed with a photo of Mike and his pals, shot from behind, matching in their bright briefs.

"Great way to start the year with a little dunk for @doddie_aid #doddieaid2023 before heading to Cheltenham, was a little chilly in there!!! Now it's time to get the miles in! If you are feeling active head to Doddieaid.com and join team barbarians," Mike captioned the clip, encouraging followers to join his virtual team.

Mike Tindall/Instagram

The former Team England rugby player announced on Instagram last week that he would be participating in the Doddie Aid challenge, and his barely-there swimsuit was no surprise for those who followed him on the latest season of I'm a Celebrity…Get Me Out Of Here!

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In the fall, Zara Tindall's husband toughed it out in the Australian jungle on the U.K. survival reality show, finishing in fourth place. During his time in the competition, he became known for wearing cheeky swimsuits, and later released a limited-edition line of briefs to fundraise for a cure for Parkinson's disease, Hello! reported. Mike's father, Philip, has suffered from Parkinson's for the past 20 years, having undergone numerous treatments and suffering physical decline.

Though Mike was without technology during his time in the jungle, managers who ran his social media accounts while he was away posted a tribute to Weir following his death in November.

"We know Mike will be very sad about the passing of Doddie Weir. Someone who meant a lot to him," the tribute read, captioning a throwback photo of Mike with Weir (pictured above in a plaid suit). "🌹 On behalf of us all we would like to pass on our condolences to the Weir family," the caption concluded.

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Weir established the My Name'5 Doddie Foundation in November 2017, five months after announcing his diagnosis. To date, Doddie Aid has seen 30,000 participants clock over four million miles of exercise and raised over $2.3 million for the rare neurological condition.