them. The New York Times also weighed in.

[melting]

They booked a Formula One track in northern Italy at a place called Monza, which had a loop that they felt would be optimal in terms of the flatness, the altitude, oxygen levels, temperature, humidity. And they hired dozens of the world’s best runners to act as pacemakers. They didn’t schedule a date for this race. They scheduled a launch window.And until a day or so before the race, nobody knew exactly when it was going to start because they were watching the weather forecasts to get everything optimal. So they were thinking, how can we make this race as fast as possible?So this was in May 2017. And three runners going for it. Before the halfway mark, two of the runners had already fallen off pace. There was a real sense of emerging panic that this thing is going to fizzle out pathetically without even coming close.

But one guy, Eliud Kipchoge, who is the reigning Olympic champion, stuck with the pacemakers and got to about 20 miles into the race. And people started to nudge each other saying, “Oh, my God, I think he’s going to do it.”And then at that point, he just subtly started to bleed a few seconds here and there. And he ended up drifting off and running two hours, zero minutes, and 25 seconds.So he was less than a second per mile off, but two-and-a-half minutes faster than the world record at the time. But the time on the clock was faster by a huge chunk than anyone had ever done before. And that was just baffling to see. It was really, you know, it changed my perceptions and I think a lot of other people’s perceptions of how fast a person can move his or her legs over that distance.

Kipchoge didn’t make sub-two. But he still ran the length of a marathon faster than any other human had before. And the run brought a lot of attention to the Vaporflys. People started to think these things might actually work.Nike commissioned a study that showed that runners who wear them are 4 percent more efficient. Meaning, all else being equal, they burn about four percent less energy when they wear them. The New York Times also weighed in. Using publicly available running data, it confirmed that amateur marathoners who use the shoes really do run a few percentage points faster.