China's Chen Ding, Guatemala's Erick Barrondo, Russia's Valeriy Borchin and China's Wang Zhen (R-L) compete in the men's 20k race walk during the London 2012 Olympic Games at The Mall August 4, 2012. Ding, 19, set a new Olympic record with a time of 1:18:46, finishing 11 seconds ahead of Barrondo and Wang, who took silver and bronze respectively. REUTERS/Paul Hackett (BRITAIN - Tags: SPORT OLYMPICS SPORT ATHLETICS)