Participants run through coloured powder during the YARKOcross colour run race in Almaty, Kazakhstan, June 5, 2016. (Photo by Shamil Zhumatov/Reuters)

Participants climb a 10km muddy obstacle course during the “Run Mud” race, on March 29, 2019 in the Israeli mediterranean coastal city of Tel Aviv. Over 6,000 participants took part in the obstacle race, with up to 18 artificial obstacles on three tracks (10 km, five km or two km). (Photo by Jack Guez/AFP Photo)

This picture taken on February 23, 2014 shows participants wearing dresses running half-naked in the annual 3.5 km Undie Run held in the Olympic Forest Park smog-covered Beijing. Some 200 participants took part in this event, many of them with gas masks, as dangerous smog blighted swathes of northern China in recent days. (Photo by AFP Photo/STR)

Competitors take part in the Christmas Really Wild Mud Run on a 4.6 miles course across undulating farm land at Celtic Camping, St David's, Pembrokeshire, Wales, December 12, 2015. (Photo by Rebecca Naden/Reuters)

Participants take part in the Color Run near the Eiffel Tower in Paris April 19, 2015. The Color Run is a five-kilometre race, held in cities across the U.S. and also worldwide, with the aim of promoting healthy living and to benefit a charity that organizers choose in each of the cities that the run visits. Participants are doused from head to toe in different colors at each kilometre. (Photo by Benoit Tessier/Reuters)

A participant runs through foam during the Love Foam Run race in Hsinchu, Taiwan May 29, 2016. (Photo by Tyrone Siu/Reuters)

The “Hoegh Osaka” ro-ro cargo ship, operated by Hoegh Autoliners AS, sits grounded on Bramble Bank in the Solent near Cowes, on the Isle of Wight, U.K., on Monday, January 5, 2015. The car transporter was deliberately grounded after developing a list, shortly after it left the Port of Southampton. (Photo by Simon Dawson/Bloomberg)

Competitors in costume cross a water obstacle during the Wildsau Dirt Run (Wild Boar Dirt Run) obstacle course fun race at Hellsklamm ravine in Obertriesting, Austria, October 22, 2016. (Photo by Heinz-Peter Bader/Reuters)