Participants of the Sarenza High Heel Race 2015 warm up prior to the race during a party of the online shoe store, in Paris, Thursday, October 15, 2015. Competitors in teams of three girls race wearing shoes with more than 8 cm-high heels. (Photo by Francois Mori/AP Photo)

Competitors ride a home-made vehicle without an engine on a downhill track in the Red Bull Soapbox Race in Santiago, Chile, November 27, 2016. (Photo by Jonathan Faus/Reuters)

A member of Team Chez Victor falls in the water while competing during the Ice Canoe race at the Quebec Winter Carnival in Quebec City, February 5, 2017. (Photo by Mathieu Belanger/Reuters)

In this Saturday, April 8, 2017 photo, a keeper walks camels to the Al Marmoom Camel Racetrack, in al-Lisaili about 40 km (25 miles) southeast of Dubai, United Arab Emirates. Camel racing is a big-money sport and fast thoroughbreds can fetch well over a million dollars. As rising temperatures across Gulf Arab countries signal the end of the winter camel racing season, Dubai is wrapping up its races with the annual Al Marmoom Heritage Festival that has drawn thousands of camels from across the oil-rich Gulf. (Photo by Kamran Jebreili/AP Photo)

Colorado Gov. John Hickenlooper shows off his socks--one with Democratic presidential candidate Bernie Sanders and the other with Republican candidate Donald Trump – before entering his former brewpub for a book signing event to mark the release of his autobiography Thursday, May 26, 2016, in Denver. Hickenlooper, who is term-limited, is doing book talk rounds this week, reviving speculation that he is positioning himself to join Hillary Clinton's presidential campaign ticket. (Photo by David Zalubowski/AP Photo)

Participants compete in the Mud Day Race extreme run competition at El Goloso military base, outside Madrid, Spain, June 11, 2016. Thousands of athletes got covered in mud as they celebrated International Mud Day running a 13-kilometer obstacle course on a sunny Saturday with heatwave-like temperatures up to a 29 degrees Celcius (around 84 degrees Fahrenheit). (Photo by Juan Medina/Reuters)

Trees grow through the windshield of a 1937 Chrysler Imperial as it sits at Old Car City, the world's largest known classic car junkyard Thursday, July 16, 2015, in White, Ga. Over 4,000 classic cars decorate 32 acres of forest which have been turned into a junkyard museum by owner Walter Dean Lewis. The two grew up playing in the cars on the lot which started as a general store selling auto parts in 1931 by Lewis' parents. Lewis stopped selling parts about six years ago when he realized he could sustain the business more as a museum, charging $15 for visitors just looking, and $25 for photographers. Many of the cars have never moved in over 30 years and in some cases, trees now grow through them, even lifting some off the ground. (Photo by David Goldman/AP Photo)

A worker looks at an old soviet tank T-34 (L) as he fixes military vehicle (R) at a Phaeton museum in Zaporizhia, Ukraine, August 11, 2015. The museum stopped the restoration works of their collection of about 120 retro autos and motorcycles to help the Ukrainian army to restore military vehicles and equipment which will be used in the conflict in Ukraine eastern regions. (Photo by Gleb Garanich/Reuters)