Young gymnasts practice pull-up on a bar at a gymnasium of a sports school in Jiaxing, Zhejiang province April 11, 2015. (Photo by William Hong/Reuters)

People are reflected in mirrors as they walk in a busy shopping district in Tokyo, Japan, December 25, 2015. (Photo by Thomas Peter/Reuters)

Ukrainian Air Force officers attend a graduation ceremony at the National University of Defence of Ukraine in Kiev, April 24, 2015. (Photo by Gleb Garanich/Reuters)

Turkish artist Nezaket Ekici performs a live art performance entitled 'Emotion in Motion' on the first day of Art Basel 2015, Hong Kong, China, 13 March 2015. The Hong Kong show of Art Basel features 233 galleries from 37 countries and territories, presenting works ranging from the Modern period of the early 20th century to the most contemporary artists of today, according to the official press release. (Photo by Alex Hofford/EPA)

Models walk the runway at the Maria Escote show during Madrid Fashion Week Fall/Winter 2015/16 at Ifema on February 10, 2015 in Madrid, Spain. (Photo by Carlos Alvarez/Getty Images)

A model is filmed backstage before the Jeremy Scott Fall/Winter 2015 collection presentation at New York Fashion Week February 18, 2015. (Photo by Andrew Kelly/Reuters)

A model presents a creation during the 2015 Victoria's Secret Fashion Show in New York, November 10, 2015. (Photo by Lucas Jackson/Reuters)

A model presents a creation during the 2015 Victoria's Secret Fashion Show in New York, November 10, 2015. (Photo by Lucas Jackson/Reuters)