A swimmer competes during the UK Cold Water Swimming Championships at Tooting Bec Lido in south London January 24, 2015. (Photo by Luke MacGregor/Reuters)
A competitor dressed up as Santa Claus jumps into the sea during the 102nd Barcelona Traditional Christmas Swimming Cup at the Old Harbour of Barcelona on December 25, 2011 in Barcelona, Spain. (Photo by David Ramos/Getty Images)
Swimmers in fancy dress splash as they participate in the New Year's Day Loony Dook swim at South Queensferry, Scotland January 1, 2015. (Photo by Russell Cheyne/Reuters)
Ice swimmer Klaudia prepares to swim in a filled up water kettle in an ice cave inside the Nature Ice Palace, with a hight of 3,250 meters (10,663 feet) above sea level, at Hintertux Glacier near Hintertux, some 480 kilometers (298 miles) western of Vienna, Austria, 28 July 2018. (Photo by Christian Bruna/EPA/EFE)