For nearly a decade Kenichi Ito has been perfecting a running style based on Africa's wiry Patas monkey.
And it's meant that the 29-year-old now has a Guinness world record for the fastest time running 100 metres on all fours, at just under 20 seconds.
Ito explains how it all started:
You know my face and body kind of looks like a monkey, so from a young age everyone used to tease me, saying 'monkey, monkey'. But I wasn't really bothered because I really liked them, and somewhere inside of me I had this ambition to adopt one of their traits. So when I occasionally saw a monkey that could run fast, I knew I'd found it. From that point on, I practised running like a monkey every day.
For eight-and-a-half years Ito has walked around his local area in Tokyo on his hands and feet, and turned his household chores into challenges on all fours.
However it hasn't all been easy:
In the streets around here I get stopped by the police, so I went up into the mountains for about a month for a kind of four-legged running training camp. But on the first day, a hunter mistook me for a wild boar, and he tried to shoot me.
Constantly honing his style, Ito looks for inspiration from across the animal world and uses the internet and a season ticket to the local zoo to make sure he is getting the movements just right.
So far he's developed six distinct forms of all-fours movement from his top-speed "gallop" to a more leisurely walking pace, and has even recruited about 100 converts across seven countries.
While no-one at the London 2012 Olympics will be running on their hands, Ito says athletes of the future may well be converted, to what could be thought of as a more traditional form of running.
Certainly four-legged running isn't an Olympic sport yet, but my prediction is that in 500 years time all track athletes will be running on all fours.