Gold medalists again in 2012: Serena and Venus Williams of the United States celebrate during the medal ceremony for the Women's Doubles Tennis. London 2012 Olympic Games at the All England Lawn Tennis and Croquet Club on August 5, 2012 in London, England. (August 4, 2012 - Source: Clive Brunskill/Getty Images Europe)
(L-R) Bianca Knight, Allyson Felix, Tianna Madison and Carmelita Jeter of the U.S. celebrate after they gold in the women's 4x100m relay final during the London 2012 Olympic Games at the Olympic Stadium August 10, 2012. The U.S. won the women's 4x100 metres relay in a world record time, completing the lap in a sizzling 40.82 seconds to win the title back for the first time since 1996.