Usain Bolt of Jamaica won both the men's 100m and 200m gold medals at the 2008 Beijing Olympics, setting world records in both events (9.69s in 100m, 19.30s in 200m). Asafa Powell and Tyson Gay were elite sprinters but didn't win gold in Beijing. Michael Johnson was a retired 400m specialist by 2008, having won 200m/400m gold in 1996.