In October 2019, Iliad Kipchoge became the first person to run a marathon (42,195 metres) in less than two hours. Part of this achievement is tied to the shoes worn by Kenyan runners, regardless of whether Kipchoge holds the world record for this distance, is a double Olympic champion, has won more than 13 official marathons and is known for his Recognized as one of the greatest athletes of all time. And this weekend he could set the bar even higher if he gets to the Berlin Marathon in under two hours… with a little help on his feet. Or rather at his feet.
The Berlin Marathon, due to its type of route (with a slight slope), the date on which it is run (very good temperatures) and the place in the sports calendar (optimal for annual preparation) is a favorite event of many athletes. Not only this, the last 6 world records of distance have been broken in Berlin. There have been three historical hurdles in athletics: 10 seconds in the 100 m, 4 minutes (1,609 m) in the mile and two hours in the marathon. The first two have already been moved and only the marathon remains.
When Kipchoge fell below two hours in 2019, he not only did so in an unofficial race, but he was also “helped by Horse” which marked his pace, a formation designed to resist wind resistance. and he used shoes that were not yet available for running. Public, something prohibited by the World Federation of Athletics. Three years later, that famous shoe developed by Nike has inspired the Nike Air Zoom AlphaFly Next%2 that the Kenya-born athlete will likely wear this weekend. What is special about this version? How similar are they to the 2019 prototypes?
Let’s go through the parts. As far as science goes, the answer is yes: sneakers can make us faster. In a 2017 article in Sports Medicine, Nike’s Zoom Vaporly shoes were reviewed. What does it mean that they were analyzed? Originally, the time obtained in more than half a million marathons was rated. Those using this shoe improved their time by 4%. For an amateur runner who runs a marathon in three hours, 4% means reducing their time by about 5 minutes. For shoes only. According to the study authors, these shoes “improve running economy by allowing you to maintain your pace longer.” The results seem to prove her right: Since the Zoom Vaporfly hit the market, twice as many men have completed marathons in under 2:10 and twice as many women in under 2:27. Its results have been scientifically proven, but what is the technology behind them?
Of these types of advances, secrecy is high and the exact characteristics of the shoes Kipchoge used to lose two hours, a prototype, let’s remember, have not been published. What we can do is analyze a patent that was granted to Nike in 2018 and, because of the description, are identical to those used on that occasion and similar to the Nike Air Zoom AlphaFly Next%2.
For example, in the patent drawing you can see that the cushioning zone includes a plate between the outsole and the first layer of chambers. To this add an additional plate between the cameras and another plate above the cameras, directly under the leg. All this cushioning is intended to store the energy of each stride as you land. Then come the cameras or bags.
These would also allow the accumulation of energy thanks to a very lightweight foam developed by Nike. What is done with all this energy? Introduction to carbon plate. These will split the midsole and are in charge of distributing the energy stored in the heel or toes to the rest of the shoe so that it can be used when taking off. Then, when the other foot hits the ground, the impact regenerates energy that builds up in the cushioning and is distributed by the chambers and plates immediately afterwards, so that energy can be recovered by the foot. And the cycle repeats. For 42 kms.