Are recent marathon records technologically boosted?

Since 2017, the shoe ZoomX Vaporfly NEXT%, and its previous versions, the Nike equipment manufacturer, are talking. This is the pinnacle of technological advancement for a marathon sneaker. These features provide benefits that can improve the performance of its users by up to 5%, according to the US company.

However, it is not unanimous, as evidenced by a complaint filed by a group of elite athletes with the International Athletics Federation (IAAF), according to the Times from London. Of course, our two heroes of the weekend had them on their feet, in a more advanced prototype version (alphaFLY) in the case of Kipchoge.

The sole of the ZoomX Vaporfly NEXT% is composed of a carbon plate between two layers of foam, which would allow a better economy of race. The shoe is optimized to reduce energy losses with respect to ground impacts, and maximize energy return in the process.

"When you count the number of steps you take on a marathon, a return of energy that is improved by even a few thousandths of a percentage, it really makes a difference," explains Anne-Laure Menard, a post-doctoral student in biomechanics. at the School of Kinesiology and Physical Activity Sciences at the University of Montreal.

For each impact on the ground, there is a better rebound, it is a little the same effect as a spring.

Eliud Kipchoge, first man to run the marathon in less than 2 hours.

Photo: Getty Images / ALEX HALADA

The IAAF rules are as follows. Athletes can compete barefoot, or wear a shoe on one or both feet. The function of the shoe is to provide protection and stability to the feet, and adequate grip on the ground. These shoes should not be designed to help or benefit athletes.

According to Jonathan Tremblay, a professor of exercise physiology at the School of Kinesiology and Physical Activity Sciences at the University of Montreal, the benefit of using this shoe for Eliud Kipchoge was no major.

"We had already predicted with the mathematical models that the maximum optimal performance of an athlete in the marathon could be around 1 h 57 min, 1 h 58 min," he explains.

Photo of a Nike ZoomX Vaporfly NEXT espadrille taken at the 2019 London Marathon

Photo: Getty Images / Joe Maher

Draw the line

Joined by Radio-Canada Sports, the International Athletics Federation acknowledged the relevance of the debate. She agrees that some forms of technology can benefit marathoners. It will soon be looking through a committee of two former athletes and experts in science, biomechanics, ethics, sports equipment and law, balancing support for technological development and integrity. Sport.

"If we put springs in a shoe, could we use it, if we realize that it improves gender performance 10%? This is where it takes a fairly clear regulation, and applies to everyone, "illustrates Anne-Laure Menard.

There is no source of energy that comes from there. We do not give energy to the runner. We're just restoring some of the energy that was lost.

And for all other runners

The ZoomX Vaporfly NEXT% is well known in the middle of the race and many have adopted it. In addition to being an expert in biomechanics, Anne-Laure Menard is also a provincial-level runner, and she has seen the attraction effect of the equipment among marathoners. She does not believe that the shoe will be banned, at least not in the short term. According to her, the key lies in accessibility.

Moreover, other equipment manufacturers also offer a sneaker equipped with a carbon plate. And progress is a very annoying thing to stop.

The shoe that will be worn in ten years will be much better than the one we wear today.

Remains a real point likely to insurrection. The prohibitive price of the shoe that drains, when available, for a sum approaching $ 330. A situation that, if left unchanged, could be a barrier to accessibility.

Basic elements to consider for the IAAF when deciding on the issue.