Times have plummeted in long-distance road races and critics suggest some top trainers are artificially boosting performance.
Such is the concern that World Athletics – the sport’s governing body – has assembled a panel of experts to examine the legality in professional competition of a range of modern footwear.
The shoes, as well as similar models from other brands, feature thick soles and carbon plates that act like springs.
“Universality of Athletics”
World Athletics rules state that footwear “shall not be designed in such a way as to give athletes an unfair assist or advantage”.
Rule five adds: “Any type of footwear used must be reasonably accessible to all in the spirit of the universality of athletics.” The Vaporfly Next% are widely available at retail at a cost of over $300.
The wording also indicates that shoes found not to conform “with the rules or the spirit thereof” could be banned from competition.
In a recent statement, World Athletics said a task force, including officials, athletes, scientists and lawyers, was reviewing shoe technology and rule wording.
A decision is likely by the end of this month, but any changes must be approved by the World Athletics Council, according to a spokesperson. CNN has reached out to Nike for comment but has yet to receive a response.
“We have to go with the technology”
Kenyan Kipchoge set the official marathon world record of two hours one minute 39 seconds in Berlin in September 2018 and clocked 1:59.40 in the INEOS 1:59 Challenge special stage in Austria. His support runners in Vienna also wore the Vaporfly shoes.
Kipchoge has compared running a sub-two hour marathon to Neil Armstrong’s historic moon landing in 1969 and the Kenyan sees nothing wrong with the advancement in shoe design.
Swimming is another sport that has had to deal with the consequences of technological advances.
After 17 world records fell at the European Short Course Championships later that year, the International Swimming Federation (FINA) changed its rules regarding swimwear length and material.
“Is Kipchoge an outlier with immense athletic potential? Or is he just a very good runner who benefits from the immense improvements his shoes bring? Maybe both.
“But the thing is, we don’t know with absolute certainty. Running, especially the marathon, is supposed to be the purest thing humans put themselves through. It’s just about the feet, the legs, the lungs , heart and brain. These shoes create the same problems as doping.”