On October 19, 2019, Eliud Kipchoge ran a marathon in less than two hours, breaking one of the sport’s greatest barriers. The following day, fellow runner Kenyan Bridget Kosgey shattered the women’s marathon record. What both of these runners had in common was what was on their feet.
Both athletes had worn Nike’s Vaporflys. The shoes, as Nike claims, are supposed to improve running times by up to 4.2%, and if recent records are any indication, those claims may have valid backing.
Since the Vaporfly’s release, male runners wearing the Nike shoes have run nine of the top 10 fastest marathon times. Yet Nike’s recent record successes have ignited a fierce debate about whether the Vaporfly shoes should be prohibited from competition. Until now, track’s international governing body, World Athletics, has only one singular loose guideline regarding sneaker technology.
“Shoes must not be constructed so as to give athletes an unfair assistance or advantage.” according to the rulebook.
However, the rule does not explain how these two values are to be measured. To ensure the integrity of running competitions, there must be modern regulation to counteract the new revolutionary technology displayed by Vaporflys.
Running shoes have consistently evolved in parallel with spikes in running popularity. This includes the Waffle trainer of 1974; Nikes original running shoe developed by co-founder Bill Bowerman, replicated the grooves of a waffle iron to help grip the track. Followed by the development of the air cushion in 1976 and maybe the most impactful discovery of all: EVA foam in the mid-70s. Also known as Ethylene Vinyl Acetate, EVA is a lightweight, flexible foam used even in modern shoes. The foam is equipped with superior cushioning and shock-absorption properties. Unlike the heavier, less resilient Polyurethane that preceded it, EVA’s ability to compress and rebound enhanced performance ultimately allowing Bill Rodgers to break 2:10 in the marathon at the 1975 Boston Marathon. These discoveries contributed to the creation of the standard running shoe, consisting of three main components: a tight upper region, a cushioned middle and the less-important outsole.
In contrast, regulation has not yet adapted to changing technology. The Pebax foam used in the Vaporflys has a staggering 85 percent energy consumption rate, referring to the efficiency of the foam in returning energy to the runner during their stride. The Vaporsflys yield 85% of the energy used by the runner, a 20% increase from previous models. Means runners can expend more energy without the risk of fatigue, resulting in potentially faster times, especially over long distances.
Jeff Burns, a professional ultra runner, co-authored a paper where he argues for a compromise between those who oppose the shoes’ use in competition and those who see the Vaporflys as the next phase in the sport’s technical innovation. Burns proposes a universal standard in shoe’s midsole thickness during competition, while still allowing for the existing shoes to be used during competition. Thus allowing shoe designers to abide by some sort of design regulation without putting constraints on innovation or differentiation, therefore creating a level playing field for athletes as athletic ability would take precedence over the type of foam on their feet.
This response to sports tech innovation isn’t without precedent. During the 2008 Olympics in Beijing, Speedo’s Laser bodysuit was the swimmer’s status quo gear. Its revolution in swimwear design cut down on the body’s friction and helped athletes shatter existing swimming records almost overnight.
World Aquatics, the world governing body of swimming, banned the suit after an exceptional number of swimmers broke world records in it. But World Aquatics policy, like Burns’s proposal, was a compromise. Although full-length suits were banned, the Laser’s revolutionary material is still permitted, establishing adequate regulation while leaving space for future development.
Ultimately, Midsole length regulation must be established by World Athletics as a response to future athletic innovation, by establishing a universal midsole length the Track and Field world could ensure technological integrity and innovation alongside an equal playing field for it’s athletes without their shoes being a factor. Only by properly addressing the unfair advantages new gear can give athletes can we maintain running integrity within a fast-developing sports technology world.
