A woman runs through the early morning mist on Hampstead Heath on September 30, 2011 in London, England. Much of the UK is enjoying a spell of unseasonably hot weather which is expected to last into next week. (Photo by Dan Kitwood/Getty Images)

Qian Hao's imported Pekingese dog, Mixiu, runs in a park in Beijing, China, February 8, 2018. (Photo by Thomas Peter/Reuters)

Brides-to-be participate in the “Running of the Brides” race in a park in Bangkok, Thailand March 25, 2017. (Photo by Athit Perawongmetha/Reuters)

Participants take part in an extreme run “Bison race” near the town of Logoisk, Belarus September 17, 2016. (Photo by Vasily Fedosenko/Reuters)

A participant competes in the “Farinato Race” winter extreme run competition in Gijon, northern Spain, January 31, 2016. (Photo by Eloy Alonso/Reuters)

A rickshaw man runs under the blooming cherry blossoms in Tokyo, Sunday, March 29, 2015. (Photo by Shizuo Kambayashi/AP Photo)

A woman takes part in a “Brave Run” competition in Minsk October 4, 2015. (Photo by Vasily Fedosenko/Reuters)

A group of children run into a fountain on the South Bank on August 1, 2011 in London, England. Temperatures in the capital reached around 27 degress today and are expected to hit 30 degrees by Wednesday. (Photo by Dan Kitwood/Getty Images)