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Just a few years ago, no one thought a human could run a marathon in under two hours. But yesterday in Berlin, Eliud Kipchoge shattered the world record and ran 26.2 miles in 2 hours, 1 minute and 39 seconds. Two hours now seems inevitable. NPR's Eyder Peralta reports on how humanity got here.
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UNIDENTIFIED PERSON: Crowds at the German capital roar him on.
EYDER PERALTA, BYLINE: By the time he runs under the Brandenburg Gate, Eliud Kipchoge knows he's about to shatter the world record.
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UNIDENTIFIED PERSON: He comes towards the line, raises a sprint on those magical legs. And at last the world record is his.
PERALTA: Kipchoge breaks the world record by more than a minute, an almost unbelievable feat. But one thing that was not a surprise is that a Kenyan was breaking another Kenyan's world record. Just think about this. Last year, 187 men ran marathons under 2 hours and 10 minutes; 113 of them were Kenyans, but only one American made that list.
ADHARANAND FINN: Kenyans have this brilliant ability not to fear running, not to see it as something that's going to hurt but just to accept it.
PERALTA: That's at Adharanand Finn. He's the author of "Running With The Kenyans," which dissects why Kenyans are such good runners. He explored the high altitude, their high-carb diet, their monk-like dedication. But he couldn't pin down a secret sauce.
FINN: It's a whole combination of factors coming together. It's, like, the perfect storm of circumstances, really.
PERALTA: This hunt for a sub-two-hour marathon started more than a year ago for Kipchoge. Nike, his sponsor, poured tons of money into finding the perfect conditions for a human to overcome that hurdle. They studied humidity and how to reduce lactic acid. They redesigned shoes and set up a test run.
National Geographic produced a documentary in which Kipchoge comes off as a Zen master - a tranquil smile, a seamless running form and a metaphysical outlook. This is not about legs, he says. It's about the heart and mind.
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ELIUD KIPCHOGE: I feel that I have a potential inside my heart that I can go beyond human limitation.
PERALTA: In the end, he missed the two-hour mark by a mere 25 seconds. Kipchoge wasn't awarded the world record because the course didn't meet the specifications. But at the time, it put the two-hour marathon within reach.
PETER WEYAND: The elephant in the room is the shoes on his feet.
PERALTA: That is Peter Weyand, who studies the limits of human performance at Southern Methodist University. He says sports companies have been trying to make a better running shoe for decades. And in the past few years, Nike seems to have hit jackpot with the Vaporfly 4 percent. According to a 2017 peer-reviewed study, an elite athlete can run 3.5 percent faster with those shoes.
WEYAND: But if you accept the results so far, then they are performance-enhancing shoes.
PERALTA: So in Weyand's mind anyway, it puts Kipchoge's feet in question because Dennis Kimetto did not run in those shoes when he set the marathon record back in 2014. Eyder Peralta, NPR News, Nairobi. Transcript provided by NPR, Copyright NPR.
