Mud Madness at the annual Jaffa Cakes charity three-mile run at Foymore Lodge near Portadown this afternoon, on April 13, 2014. A total of a thousand competitors and fun-runners took part in the two races held over the mudstrewn endurance course. (Photo by Alan Lewis/Photopress Belfast)

Nine year old girl Barsati reacts while walking on a tightrope in Mumbai on February 11, 2014. Barsati, and her younger brother Rajababu, (4) earn an average of around 2000 rupees (32 dollars) per day from pedestrians and tourists performing various acts on the tightrope near the city's iconic landmark Gateway of India. (Photo by Indranil Mukherjee/AFP Photo)

A model poses at Checkpoint Charlie, a historic place in the German capital to promote the fashion magazine “Sous” on June 12, 2012. (Photo by Maurizio Gambarini)

A participant prepares for the Red Bull Air Race World Championships in Abu Dhabi, United Arab Emirates on February 6, 2017. (Photo by Red Bull Content Pool/SIPA Press/Rex Features/Shutterstock)

St Andrews University students skinny dip in the sea as May Day celebrations in St Andrews, Scotland on April 30, 2017. Hundreds of revellers ditched their clothes and bravely jumped into the bitterly cold North Sea. (Photo by Alamy Stock Photos)

Skiers and snow boarders descend from a slope as they attempt to break the record for mass skiing in swimming suits at Rosa Khutor resort near Sochi, Russia, April 9, 2016. (Photo by Kazbek Basayev/Reuters)

A man stands next to a barricade blocking a road during a protest calling on the government to help ease the economic effects of an harmful algal bloom that had affected their livelihoods at Chiloe island in Chile, May 6, 2016. (Photo by Pablo Sanhueza/Reuters)

U.S. Corporal Stanley Suski, left, and Miss Tamako, a Geisha girl, whirl a bit of Jitterbug, in a bar, in Tokyo, Japan, on October 1, 1945. (Photo by AP Photo)