Eunice Jepkoech Sum (R) of Kenya reacts as she wins ahead of Mariya Savinova (L) of Russia and Alysia Johnson Montano of the U.S. in the women's 800 metres final during the IAAF World Athletics Championships at the Luzhniki stadium in Moscow August 18, 2013. REUTERS/Lucy Nicholson (RUSSIA - Tags: SPORT ATHLETICS)