When 23 year-old Kenyan Kelvin Kiptum broke the marathon world record in Chicago last Sunday – the first man to finish in under 2:01:00 hours – he received an awful lot of attention… for his shoes. Kiptum was wearing the new Nike Alphafly 3, as was women’s race winner, 30 year-old Dutch runner Sifan Hassan.
Hassan broke the course record with the second fastest ever women’s marathon time of 2:13:44. The fastest ever? Just two weeks earlier in Berlin Tigist Assefa broke the women’s world record by over two minutes wearing the Adizero Adios Pro Evo 1. In Chicago, 32 year-old Kenyan Benson Kipruto sported the Evo Pro 1 and finished three minutes behind Kiptum. The Runner’s World headline read “Nike surges ahead in the “war of the super shoes.’”
Running changed forever at the 2016 Olympics when two male medallists clambered onto the podium in prototype versions of the first ever super shoe, the Nike Vaporfly 4 per cent. Named 4 per cent because the shoe improves a competitor’s “running economy” – the amount of oxygen consumed per minute – by four per cent, every running brand has since launched their own version. Marathon running has become a Formula One-style battle of technology as much as a triumph of human endurance. “When these shoes first came out people were saying that wearing them was cheating,” explains Rick Pearson, senior editor at Runner’s World. “It makes a mockery of the records of the past. Excellent runners have seen their place in the all-time list fall to new runners because they have far better shoes.”
The first super shoes were invented in Nike’s R&D lab, initially in one part of the Mia Hamm building on Nike’s Oregon campus, but now housed in the highly restricted LeBron James Innovation Center where biomechanics researchers, robotics experts, materials scientists and computational designers work on microscopic improvements to shoe design. The breakthrough Alphafly – and its successors – combine PEBA (polyether block amide) foam that’s lightweight and has an unusually efficient energy return with a carbon fibre sole. However much energy you apply in crushing PEBA foam is delivered more or less 100 per cent back as the foam expands. The carbon fibre plate helps roll your foot – known as a rocker design – making it easier to use the returned energy to propel yourself forward. So useful were the early shoes that athletes sponsored by other brands would sport these Nikes and try to hide the famous swoosh logo with black marker pen. “I don’t have to tell you about the Olympic committee’s bias against American brands,” one Nike designer told Tortoise. “These shoes changed that forever.”
The designs rapidly reached the mass market – it’s a World Athletics rule that racing shoes have to have been on sale to the public for a month before a race – where all the weekend marathon heads and park run racers who can afford £200 per pair are getting performance increases of anything up to 9 or 10 per cent. The Adizero Adios Pro Evo 1 retails for around £400, weighs just 138gms – about the same weight as a box of 100 paper clips – and are reportedly only designed to last for one race. “It is a bit rich to sell a £400 pair of shoes you can wear for 50 miles when running shoes are so non-biodegradable that pretty much every pair of running shoes ever made is still in existence,” says Pearson. “But these shoes will keep coming because they make so much money for brands.”