The beard of a skater, one out of some 1,100 athletes, is covered with ice and snow during the 200 km (124 miles) speed skating race in the Carinthian village of Techendorf January 30, 2015. Techendorf is hosting the Alternatieve Elfstedentocht Weissensee (Alternative Eleven City Races Weissensee) races, a traditional Dutch series of speed skating events for both professionals and amateurs with some 5,000 participants, until January 31, 2015. (Photo by Leonhard Foeger/Reuters)

A charity runner dressed as Father Christmas steps out of a portable toilet ahead of the “Santa Run” charity fun run in Stockholm on December 10, 2017. Hundreds of participants dressed in Santa suits and wearing white beards ran through the streets of the old town in Stockholm in an all charity run. (Photo by Jonathan Nackstrand/AFP Photo)

Participants dressed as Santa Claus gather shortly before the 4th annual Michendorf Santa Run (Michendorfer Nikolauslauf) on December 9, 2012 in Michendorf, Germany. Over 800 people took part in this year's races that included children's and adults' races. (Photo by Sean Gallup)

A woman rides a mechanical bull before participating in the 4th annual Running of The Bulls October 15, 2011 in Cave Creek, Arizona. (Photo by Joshua Lott/Getty Images)

People take part in the Cupid's Undie Run in the Manhattan borough of New York February 7, 2015. The run, held to raise funds to combat children's tumors, sees runners in their underwear partying and running along the West Side Highway. (Photo by Carlo Allegri/Reuters)

People take part in The Color Run in Brussels, Belgium September 6, 2015. The Color Run is a five-kilometre, untimed race, held in cities worldwide, with the aim of promoting healthy living. Participants are doused from head to toe in different colors at each kilometre. (Photo by Yves Herman/Reuters)

A participant sets off on a penny-farthing bicycle at the start of the The Tweed Run in central London, Britain, May 14, 2016. The Tweed Run, a very British public bicycle ride through London's streets, with a prerequisite that participants are dressed in their best tweed cycling attire. (Photo by Hannah McKay/Reuters)

Brides-to-be participate in the "Running of the Brides" race in a park in Bangkok November 28, 2015. A hundred husbands and wives-to-be wore their wedding dresses and running shoes and competed in an event for a combined prize worth 1 million Thai baht ($27,928), according to the organisers. (Photo by Athit Perawongmetha/Reuters)