Kenichi Ito: The 'world's fastest man on four legs' Kenichi Ito, known as the "world's fastest man on four legs" broke a new Guinness World Record today for running the 100 metres on all fours in 17.47 seconds. Ito developed his skills over a period of nine years by basing his running style on the African Patas monkey. Usain Bolt defended his men's 100m title on two legs in London 2012, winning the final in an Olympic record time of 9.63 seconds.