An ice swimming enthusiast dressed as Neptune takes to the frigid waters of Orankesee lake during the 27th annual "Winter Swimming in Berlin" on January 8, 2011 in Berlin, Germany. A local swimmers' group called the “Berlin Seals” invite ice swimmers from across Germany and abroad to the annual event. Members claim ice swimming is good for the body's blood circulation. (Photo by Sean Gallup)

A female swimmer reacts after finishing the competition in a pool carved from thick ice covering the Songhua River during the Harbin Ice Swimming Competition in the northern city of Harbin, Heilongjiang province, January 5, 2016. The swimming competition was held on the official launch day of the Harbin International Ice and Snow Sculpture Festival. (Photo by Aly Song/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)

A instructor (2nd L) from the Philippine Mermaid Swimming Academy assists participants of a monofin swimming summer workshop as they practise floating in the water of a private pool in Paranaque city, metro Manila April 5, 2014. The Philippine Mermaid Swimming Academy workshops, which were originally conducted on the beaches of Boracay Island, central Philippines, currently cost 1,800 pesos per person ($40) for a two-hour session. (Photo by Romeo Ranoco/Reuters)

Patrick Hausding and Stephan Feck of Germany compete in the men's 3-meter synchro springboard preliminary competition at the FINA Swimming World Championships in Barcelona, Spain, Tuesday, July 23, 2013. (Photo by David J. Phillip/AP Photo)

Visitors watch as Grigory Broverman, a member of the Cryophile winter swimmers club, pours a bucket of cold water over his 6-year-old daughter Liza during a flash mob, part of a celebration of Polar Bear Day at the Royev Ruchey Zoo in a suburb of the Siberian city of Krasnoyarsk, Russia, November 29, 2015. The air temperature was around minus 5 degrees Celsius. (Photo by Ilya Naymushin/Reuters)