2016 Rio Olympics - Athletics - Final - Women's 400m Final - Olympic Stadium - Rio de Janeiro, Brazil - 15/08/2016.Shaunae Miller (BAH) of Bahamas lies on the track after finishing first REUTERS/Dylan Martinez

2016 Rio Olympics - Athletics - Final - Women's 400m Final - Olympic Stadium - Rio de Janeiro, Brazil - 15/08/2016. Shaunae Miller (BAH) of Bahamas throws herself across the finish line to win the gold ahead of Allyson Felix (USA) of USA and Shericka Jackson (JAM) of Jamaica. REUTERS/Fabrizio Bensch

2016 Rio Olympics - Athletics - Final - Men's 800m Final - Olympic Stadium - Rio de Janeiro, Brazil - 15/08/2016. Gold medallist David Lekuta Rudisha (KEN) of Kenya, silver medallist Taoufik Makhloufi (ALG) of Algeria and bronze medallist Clayton Murphy (USA) of USA hug. REUTERS/Lucy Nicholson

2016 Rio Olympics - Athletics - Final - Men's 800m Final - Olympic Stadium - Rio de Janeiro, Brazil - 15/08/2016. David Lekuta Rudisha (KEN) of Kenya runs to win gold, ahead of Taoufik Makhloufi (ALG) of Algeria, Boris Berian (USA) of USA and Alfred Kipketer (KEN) of Kenya. REUTERS/Lucy Nicholson

2016 Rio Olympics - Athletics - Final - Men's 800m Final - Olympic Stadium - Rio de Janeiro, Brazil - 15/08/2016. David Lekuta Rudisha (KEN) of Kenya celebrates after winning the race REUTERS/Dylan Martinez

2016 Rio Olympics - Athletics - Final - Men's 800m Final - Olympic Stadium - Rio de Janeiro, Brazil - 15/08/2016. Gold medallist David Lekuta Rudisha (KEN) of Kenya celebrates. REUTERS/Dylan Martinez

2016 Rio Olympics - Athletics - Final - Men's 800m Final - Olympic Stadium - Rio de Janeiro, Brazil - 15/08/2016. Gold medallist David Lekuta Rudisha (KEN) of Kenya celebrates. REUTERS/Dominic Ebenbichler

2016 Rio Olympics - Artistic Gymnastics - Final - Women's Balance Beam Final - Rio Olympic Arena - Rio de Janeiro, Brazil - 15/08/2016. Laurie Hernandez (USA) of USA competes. REUTERS/Marko Djurica