A STUNNING ACHIEVEMENT
Marathoner’s sub-two-hour finish took consistency and cutting-edge technology
By now you’ve probably heard about Eliud Kipchoge’s record-breaking sub-two-hour marathon performed this month in Vienna. His 1:59.40 finish is the talk of the running world, including lively discussions about what it took to break the twohour barrier — an accomplishment scientists thought would be years more in the making.
Before we discuss the shoes, the route and the pacers, we need to talk about the athlete. Kipchoge, a 34-year-old Kenyan, is indisputably the best marathoner in the world, known not just for his speed but also for his consistency. (His marathon finishing times from 2013 to 2019 have ranged from 2:01.39 to 2:04.11; these times are for races where conditions weren’t controlled.) Though his latest effort didn’t qualify as a world record (more on that later), the 5-foot6, 123-pound runner holds the official world record of 2:01.39, set at the 2018 Berlin Marathon. At first glance, taking two minutes off a previous personal best doesn’t seem like a big performance leap. But for a seasoned athlete already taking advantage of the best training and nutrition that science can provide, those 119 seconds are akin to summiting Mount Everest.
All top marathoners benefit from three distinct physiological properties: an impressive VO2 max, an economical stride and the ability to run an entire marathon at the top end of their lactate threshold (the maximum effort an athlete can sustain for a specific period of time).
Some degree of each of these pillars of marathon running is genetically determined and some can be improved with training, but when it comes to being the best of the best, most experts believe that running economy is the biggest contributor to podium performances. Superior running economy translates into less energy (oxygen) expended at a given pace, which leads to faster times compared to a less efficient runner with a similar VO2 max.
Kipchoge is a model of efficiency. Add a flat course with limited turns, the perfect weather conditions — no wind, not too hot or too cold — and pacers to block wind resistance, and you’ve got an almost full set of winning conditions, all of which were in place for Kipchoge’s successful run earlier this month.
Then there are the shoes. Superior to the first-generation Nike Zoom Vaporfly Elite model he wore during his 2017 attempt to run a sub-two-hour marathon (he clocked in at 2:00.25), the model he debuted in Vienna is reputed to have improved on the four per cent saving in energy promised in Version 2 of the Vaporfly, dubbed the Vaporfly 4% (with a midsole consisting of a single carbon-fibre plate with a layer of foam above and below).
Nike hasn’t divulged the technology in the shoe Kipchoge wore to break the two-hour barrier (dubbed the Vaporfly NEXT%), but rumours suggest additional cushioning and more carbon plates have boosted energy savings to five per cent — just what he needed to improve upon those final few seconds. How big a deal are these technology-forward shoes? Since their debut in 2017, marathoners and half-marathoners wearing Vaporflys ran three to four per cent faster than their previous personal bests. The shoes, which feature a noticeably higher stack than traditional running shoes, have users commenting that they feel like they’re running on trampolines.
To further illustrate the effect of Vaporflys on performance, it’s worth noting that from 2006 to 2018 only one or two runners broke 2:12 at the Chicago Marathon. This year’s race, which took place Oct. 13, had 10 finishers under 2:12. The International Association of Athletics
Federations has addressed the controversy surrounding the technology-laden Vaporfly 4%, which sells for C$330, stipulating that “any type of shoe used must be reasonably available to all in the spirit of the universality of athletics.” The association also states: “Shoes must not be constructed so as to give athletes any unfair assistance or advantage.”
With Vaporflys on sale at local running outlets and worn by recreational and elite runners, it could be argued that they are universally available, but what constitutes an “unfair assistance or advantage” remains unclear.
Kipchoge’s shoes aren’t the only factor in the debate about the legitimacy of his record time. Purists suggest the rotating pack of pacers shielding Kipchoge from wind resistance, a lead car using a laser to keep the runners on pace and the delivery of liquid nutrition by bike (versus the runner slowing to pick up their bottle at hydration stations) combined to not only disqualify the event from the world record books, but to imply that technology has taken over from human physiology when it comes to exploring the physical limits of endurance running.
Certainly, Kipchoge’s numbers lend credence to this claim. He maintained an unbelievable
2:50 min/km pace for 42 kilometres and looked like he had plenty of gas left in the tank when he crossed the finish line, despite his blistering pace.
The true test of technology and Kipchoge will occur during his next official marathon where conditions aren’t controlled. After all, a successful marathon has always been about managing the day, which means adjusting to the weather, course and fellow competitors — all of which test the mettle of even the best runners.
Then again, he’ll still be sporting the latest in shoe technology, which will be tested in real-world conditions. Runners everywhere will be watching closely.