Caroline Wozniacki of Denmark serves in her match against Kaia Kanepi of Estonia during day four of the Toray Pan Pacific Open at Ariake Colosseum on September 28, 2011 in Tokyo, Japan. (Photo by Koji Watanabe/Getty Images)

Cheerleaders let their hair fly as they perform prior to a German first division Bundesliga soccer match between 1. FC Cologne and Bayern Munich in Cologne, Germany, March 4, 2017. (Photo by Michael Probst/AP Photo)

Participants, one of them loosing balance, jump in a sack race at a shopping center in Paris to win a 500 euros voucher (537 USD), on the first day of the winter sales in Paris, France, Wednesday, January 6 , 2016. The five-week 2016 winter sales start everywhere across France on Wednesday Jan. 6 and end on Feb. 16. (Photo by Francois Mori/AP Photo)

Members of the Royal Navy respond to a simulated fire in a Vanguard-class submarine control room training facility at Clyde naval base in Faslane, Scotland on January 21, 2016. (Photo by Photograph: Danny Lawson/PA Wire)

A U.S. Army soldier with the 10th Special Forces Group and his military working dog jump off the ramp of a CH-47 Chinook helicopter from the 160th Special Operations Aviation Regiment during water training over the Gulf of Mexico as part of exercise Emerald Warrior 2011 on March 1, 2011. (Photo by Tech. Sgt. Manuel J. Martinez/U.S. Air Force)

A devotee with his body painted poses as he waits to perform during a ritual as part of the annual Shiva Gajan religious festival at Sona Palasi village, in West Bengal, India, April 11, 2016. Devotees offer sacrifices and perform acts of devotion during the festival in the hopes of winning the favour of Hindu god Shiva and ensuring the fulfillment of their wishes, and also to mark the end of the Bengali calendar year. (Photo by Rupak De Chowdhuri/Reuters)

Participants dance and climb on an art installation as approximately 70,000 people from all over the world gather for the 30th annual Burning Man arts and music festival in the Black Rock Desert of Nevada, U.S. August 31, 2016. (Photo by Jim Urquhart/Reuters)

A veterinarian kisses an 8-month-old cat, wearing a prosthetic two-wheel device, at a veterinary hospital in Chongqing municipality, March 16, 2015. The cat's rear legs lost the abilty to walk after falling from the ninth to fifth floor of a building last November, its since undergone four major surgeries which included removing parts of its organs, local media reported. (Photo by Reuters/China Daily)