‘Supershoes’ have changed running but do they confer unfair advantages? Premium

A few years ago, the Nike Vaporfly shoe kicked off a storm of controversy in athletics. It became a focus for claims about whether it provided some athletes with an unfair advantage

On the face of it, competitive distance running appears not to have changed much since the Olympic Games were revived in 1896. However, even the relative simplicity of racing from gun to tape has radically altered in recent years due to the rise of advanced running footwear known colloquially as “supershoes”.

A few years ago, the Nike Vaporfly shoe kicked off a storm of controversy in athletics. It became a focus for claims about whether it provided some athletes with an unfair advantage over those not equipped with the shoes.

In 2019, Kenyan distance runner Eliud Kipchoge wore prototype Vaporfly shoes when he became the first athlete to run the marathon distance in under two hours as part of the Ineos 1:59 challenge in Vienna. Ultimately, the shoes avoided a ban just in time for the 2020 Tokyo Olympics.

Several years on, what more do we understand about these shoes and how they work? My recent paper attempts to review and answer ten key questions about supershoes as the Paris Olympics now loom on the horizon.

First, we need to understand what supershoes are and how they differ from traditional running footwear. Initially, supershoes used a sole that saw a combination of material called a polyamide block elastomer (known by its tradename Pebax) coupled with the use of a carbon fibre plate.

At the height of the controversy, much was made of this plate, leading to claims that they were essentially springs propelling runners along. However, scientists now understand that, generally speaking, it’s the combination of all of the soles’ components working together harmoniously that’s behind the shoes’ success.

This broad effect has helped topple a raft of world records in the marathon and half-marathon distances. The shoes have improved times by roughly 1.4-2.8% or 0.6-2.2% in the men’s and women’s marathon events respectively over the last seven to eight years.