A Tibetan rider fires his weapon as he perfoms his riding skills at the Qinghai Yushu Horse Racing Festival on July 27, 2007 in Yushu County of Yushu Tibetan Autonomous Prefecture, Qinghai Province, northwest China. The Horse Racing Festival of Tibetan nomads in Yushu Prefecture falls in late July and early August on the Tibetan calendar. During the festival, various equestrian skills will be performed along with singing, dancing and costume shows. (Photo by China Photos/Getty Images)

A bride stretches before the event during the “Running of the Brides” race, in Bangkok, Thailand, December 2, 2017. Six hundred of to be brides and their grooms compete a run race aimed to win more than two million baht (61,000 US dollars or 51,000 euro) of wedding package prizes including a pair of white gold diamond rings and honeymoon trip to the Maldives. (Photo by Athit Perawongmetha/Reuters)

A participant jumps on vintage skis during a traditional historical ski race in the northern Bohemian town of Smrzovka, Czech Republic, February 20, 2016. (Photo by David W. Cerny/Reuters)

A drunk racegoer lays on the ground as her friend tries to wake her up during the Emirates Melbourne Cup Day held at Flemington Racecourse in Melbourne Australia, on November 4, 2014. (Photo by Asanka Brendon/Rex Features)

A competitor laughs while taking part in the office chair race ISU-1 Grand Prix in Tainan, southern Taiwan April 24, 2016. It was the first time such a race was held in Tainan, as part of the “ISU-1 GP” (Grand Prix) that began in Japan in 2010, according to businesses on Jhengsing Street and Haian Road in the city's West Central District and the city's Tourism Bureau, which organized the event. The fastest rider only took six seconds to complete the 30-meter race. (Photo by Tyrone Siu/Reuters)

A competitor tries to clear a jump during the RHL Beach Race at Weston-Super-Mare on October 9, 2011 in Weston-Super-Mare, England. (Photo by Richard Heathcote/Getty Images)

In this photo provided by Andreas Langreiter via Global-Newsroom, Hannes Arch of Austria performs during the finals of the first stage of the Red Bull Air Race World Championship in Abu Dhabi, United Arab Emirates, Saturday, February 14, 2015. (Photo by Andreas Langreiter/AP Photo/Global-Newsroom)

In this May 2016 photo released by The Ocean Agency/XL Catlin Seaview Survey, a boat sails near a coral reef that has been bleached white by heat stress in the Maldives. oral reefs, unique underwater ecosystems that sustain a quarter of the world's marine species and half a billion people, are dying on an unprecedented scale. Scientists are racing to prevent a complete wipeout within decades. (Photo by The Ocean Agency/XL Catlin Seaview Survey via AP Photo)