The Kenyan long-distance runner will wear Nike’s controversial shoe for the first time in an official race at this weekend’s prestigious London Marathon. Nike’s Air Zoom Alphafly NEXT%, a version of the prototype Kipchoge wore when he ran a marathon in 1:59:40 in Vienna last October, is said to provide a 4% boost in running economy — the amount of work a runner must do at a given speed — compared with other top racing shoes. Some critics have argued that the advancement in technology is akin to doping, though Kipchoge defended the shoe ahead of Sunday’s race. “We live in the 21st century and we need to accept change,” Kipchoge told reporters. “Secondly, development goes hand-in-hand with technology. The shoe is good. We are doing a press conference virtually, is that not technology? We should accept technology and marry technology. However, not all of Nike’s elite sponsored athletes are fans of the Alphafly shoe. Ethiopian Kenenisa Bekele, who is widely seen as Kipchoge’s chief rival in the London marathon, told reporters he had suffered a series of niggling injuries and will instead be using an older version this weekend.