A member of a local swimming club holds a Russian national flag as he dives in at the start of a 24-hour swimming marathon near the western Siberian city of Barnaul March 29, 2014. Thirty members of the club will swim in turn during the event, held to mark Crimea becoming part of Russia, local media reported. (Photo by Andrei Kasprishin/Reuters)

Members of Brighton Swimming Club brave the early morning temperature to take a dip in the sea east of the pier on January 5, 2022. The club, founded in 1860, is the oldest in England. (Photo by Simon Dack/Alamy Live News)

Members of the ice swimming club “Berliner Seehunde” (Berlin Seals) take a dip in the Orankesee lake as part of their traditional Christmas swimming session in Berlin, Germany, December 25, 2015. (Photo by Hannibal Hanschke/Reuters)

Members of a local winter swimming club photograph as they take part in festive bathing in the icy waters of Boyarskoye lake outside Tomsk, Russia, December 26, 2021. (Photo by Taisiya Vorontsova/Reuters)

A member of a winter swimming club wears flippers during the celebration of Maslenitsa, also known as Pancake Week, a pagan holiday, marking the end of the winter, in Novosibirsk, Russia. (Photo by Alexandr Kryazhev/Sputnik/Profimedia)

Polar Bear club swimmers take their annual swim in the sea at Coney Island in New York City on January 1, 2014. (Photo by Curtis Means/ACE/INFphoto.com)

Members of the Coney Island Polar Bear Club warm up before swimming at the beach at Coney Island in New York, December 15, 2013. (Photo by Eric Thayer/Reuters)

This photo taken on August 7, 2016 shows mahjong enthusiasts playing mahjong under water in a swimming pool at a diving club in the Chinese city of Chongqing. Only participants with proper diving certification were allowed to take part in the underwater competition. (Photo by AFP Photo/Stringer)