Marcos Trujillo cleans the engines of a boat made by Contender in preparation for tomorrow's opening day of the four day long Progressive Insurance Miami International Boat Show at the Miami Beach Convention Center on February 15, 2012 in Miami Beach, Florida. The boat show features more than 3,000 boats and 2,000 exhibitors from all over the globe. (Photo by Joe Raedle/Getty Images)

Children attend a swim training session at Hangzhou Chen Jinglun Sport school Natatorium, where Chinese Olympic swimmer Sun Yang and Fu Yuanhui also trained, in Hangzhou, Zhejiang province, China, August 10, 2016. (Photo by Aly Song/Reuters)

A 1964 Amphicar driven by James Spear of Henderson, Nevada is shown on the boat launch after a trip to Hoover Dam during the first Las Vegas Amphicar Swim-in at Lake Mead near Las Vegas, Nevada October 9, 2015. The German-made Amphicar was produced from 1961-1968. (Photo by Steve Marcus/Reuters)

A model Cindy Bruna presents a creation on a giant catwalk installed on a barge on the Seine River during a public event organized by French cosmetics group L'Oreal as part of Paris Fashion Week, France, September 30, 2018. (Photo by Stephane Mahe/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)

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)