There is a broad consensus that the Nike Zoom Vaporfly 4% is the gold standard for modern running shoes. Eliud Kipchoge battered the marathon world record in Berlin last year wearing it, and Mo Farah is hoping that its successor, the ZoomX Vaporfly Next%, can help him beat the superhuman Kenyan when the two meet at the London Marathon on Sunday.
The design’s success has meant that rivals are now innovating all the time, perennially seeking a breakthrough that will allow them to match up to a shoe that has reset the limits of how fast a long-distance runner can go.