For more than two decades, Eliud Kipchoge ran with history on his back and won almost everything there was to win. He rewrote what the human body was believed capable of and became, by near-universal agreement, the greatest marathon runner ever. Now the 41-year-old says the chase for medals and validation is over. What I am doing is not retiring, he says. I am evolving. I am running for purpose. Kipchoge plans to take his running to the edges of the world with the Eliud Kipchoge World Tour - not to prove his greatness, but to give it away. Over the next two and a half years, the two-time Olympic champion will complete a marathon on all seven continents Continue on BBC