Horse racing is part of Naadam, a festival organized every July in Mongolia to celebrate the People’s Revolution. Using children as jockeys in such races has a centuries-long tradition. Boys and girls as young as 5 (although the law imposes a minimum age limit of 7) ride in races that can be dangerous, with hundreds of horses running across the steppe at distances of 12 to 28 kilometres at great speeds. (Photo by Tomasz Gudzowaty)

A Thai villager runs with a bullock during a catching a bullock competition as part of the annual bullock cart racing festival in Phetchaburi province, Thailand, 21 February 2016. The annual bullock cart race festival held to celebrate the end of the harvest season. (Photo by Rungroj Yongrit/EPA)

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)

Sonny Colbrelli of Italy celebrates winning the men's Paris Roubaix, a 258 kilometer (160.3 miles) one-day-race cycling race, at the velodrome in Roubaix, northern France, Sunday, October 3, 2021. (Photo by Vincent Kalut/Pool Photo via AP Photo)

Race fans watch from the grandstands as Air Force One circles the Daytona International Speedway as President Donald Trump makes his arrival to attend the NASCAR Daytona 500 auto race at Daytona International Speedway, Sunday, February 16, 2020, in Daytona Beach, Fla. (Photo by Jim Topper/AP Photo)

Greyhounds resume racing behind closed doors on June 01, 2020 in Perry Barr, England. Greyhound racing across England is returning as restrictions on sporting events are relaxed during the coronavirus pandemic. (Photo by Clive Mason/Getty Images)

Italian Moto2 rider Lorenzo Dalla Porta, Italtrans Racing Team, crashes during the race of the Motorcycling Grand Prix of Andalusia at the Jerez-Angel Nieto circuit in Jerez de la Frontera, Spain, 26 July 2020. (Photo by Roman Rios/EPA/EFE)

A couple participates in the “Running of the Brides” race in a park in Bangkok, Thailand on March 25, 2017. (Photo by Athit Perawongmetha/Reuters)