Young people wearing no pants participate in the “No Pants Subway Ride” in New York City, 13 January 2019. No Pants Subway Ride is an annual global event started in New York, USA in 2002. (Photo by William Volcov/ZUMA Press)

A model present a creation by Marina Hoermanseder during the Berlin Fashion Week Autumn/Winter 2019/20 in Berlin, Germany, January 17, 2019. (Photo by Fabrizio Bensch/Reuters)

A competitor makes their way through fire as they take part in the Tough Guy endurance event near Wolverhampton, central England, on January 27, 2019. The Tough Guy event challenges hundreds of competitors to run a gruelling course whilst negotiating up to 300 obstacles including water, fire, and tunnels. (Photo by Oli Scarff/AFP Photo)

A woman leaves sauna during the sauna marathon in Otepaa, Estonia on February 2, 2019. Participants have to track down, locate and visit designated saunas in the Otepaa area as fast as possible during the event. The team that completed all of the saunas in the shortest time wins. (Photo by Ints Kalnins/Reuters)

A team of Irish dancers celebrate after winning the under 12's group kaylee World Irish Dance Championship on April 2, 2016 in Brighton, England. The 8th World and 11th European Irish Dance Championships sees over 1500 dancers from 26 countries, speaking over 20 languages, competing in a variety of contests at the Brighton Centre on the city's beachfront. The event is organised by the World Irish Dance Association and is billed as the “Irish Dance Spectacular”. (Photo by Chris Ratcliffe/Getty Images)

The “EMIEW3” robot (R) demonstrates communicating with a visitor during a press preview in Tokyo on April 8, 2016. Japanese electronics giant Hitachi unveiled its humanoid customer service and guidance robot “EMIEW3” and “remote brain” robotics IT platform. (Photo by Toshifumi Kitamura/AFP Photo)

Hotel staff practice self-defence skills after a training session given by team member of Special Weapons and Tactics (SWAT) team, in Hangzhou, Zhejiang province, April 7, 2016. (Photo by Reuters/Stringer)

South Sudanese wrestlers take part in a wrestling match for peace in Juba on April 19, 2016. The last wrestling match for peace was held in Juba the day before civil war broke out in December 2013. (Photo by Carl de Souza/AFP Photo)