World Athletics Championships

Britain's Mo Farah, right, crosses the finish line to win the men's 5000-meter final ahead of Ethiopia's Hagos Gebrhiwet, left, and Kenya's Isiah Kiplangat Koech, second from left, at the World Athletics Championships in the Luzhniki stadium in Moscow, Russia, Friday, Aug. 16, 2013. (AP Photo/Anja Niedringhaus)

Anja Niedringhaus/AP

Britain’s Mo Farah, right, crosses the finish line to win the men’s 5000-metre final ahead of Ethiopia’s Hagos Gebrhiwet, left, and Kenya’s Isiah Kiplangat Koech, second from left, at the World Athletics Championships in the Luzhniki Stadium in Moscow, Russia, on Friday. 

United States' Inika Mcpherson competes in a women's high jump qualification at the World Athletics Championships in the Luzhniki stadium in Moscow, Russia, Thursday, Aug. 15, 2013. (AP Photo/Martin Meissner)

Martin Meissner/AP

United States’ Inika McPherson competes in a women’s high jump qualification at the World Athletics Championships in the Luzhniki stadium in Moscow, Russia on Thursday 

Germany's Lisa Ryzih competes in the women's pole vault final at the World Athletics Championships in the Luzhniki stadium in Moscow.

David J. Phillip/AP

Germany’s Lisa Ryzih competes in the women’s pole vault final at the World Athletics Championships in the Luzhniki stadium in Moscow.

Competitors jump a water obstacle in the men's 3000 metres steeplechase heat during the IAAF World Athletics Championships at the Luzhniki Stadium in Moscow...Competitors jump a water obstacle in the men's 3000 metres steeplechase heat during the IAAF World Athletics Championships at the Luzhniki Stadium in Moscow August 12, 2013.

Kai Pfaffenbach/Reuters

Competitors jump a water obstacle in the men’s 3,000m steeplechase heat during the IAAF World Athletics Championships at the Luzhniki stadium in Moscow on Monday