Marcelo Gutierrez of Colombia in action during the Valparaiso mountain bike downhill race in Valparaiso, Chile on February 11, 2018. Runners from around the world participated in the mountain bike race on the streets of the port. (Photo by Rodrigo Garrido/Reuters)

Engineer Mikhail Venin works on an antenna for the Express AM8 new generation geostationary telecommunications heavy satellite at the large-sized transformed mechanical systems centre of the Reshetnev Information Satellite Systems company in the Siberian town of Zheleznogorsk April 2, 2014. The Express AM6 is a new generation satellite providing services including Russian governmental and presidential mobile communication, digital television and broadcasting, according to the Reshetnev company representatives. (Photo by Ilya Naymushin/Reuters)

Ray Yang, a celebrity trainer, takes a selfie before the start of a workout session during TV program "The Body Show" at a gym in Seoul, September 19, 2015. Looks no longer centre only on the face in beauty-obsessed South Korea, where more women are hitting the gym to improve muscle tone and physical health. As the ideal of beauty evolves in a country that is a trendsetter in cosmetics and the pursuit of plastic surgery, women's fitness has become a growth business, say purveyors of health products, from diet supplements to dumb-bells. (Photo by Kim Hong-Ji/Reuters)

French photographer Laurent Chehere's “Flying Houses” exhibit takes workaday houses and lets them lift the imagination. The exhibit is showing at the Muriel Guépin Gallery in New York. Photo: Laurent Chehere's “Flying Houses”: “The Great Illusion”. (Photo by Laurent Chehere)

Dan McManus and his service dog Shadow hang glide together outside Salt Lake City, Utah, July 22, 2013. McManus suffers from anxiety and Shadow's presence and companionship help him to manage the symptoms. The two have been flying together for about nine years with a specially made harness for Shadow. (Photo by Jim Urquhart/Reuters)

A boy flies his kite in a cemetery in the Vila Operaria Favela of Rio de Janeiro, Brazil, July 9, 2016. (Photo by Nacho Doce/Reuters)

A window cleaner passes a lighter to his colleague while rappelling from a new building in Tianjin March 23, 2007. (Photo by Reuters/Stringer)