Carbon Plate Conundrum – Controversy Surrounding “Super Shoes” in Competitive Running

The year is 1971. Richard Nixon is president, the price of a new car is about $3,500, and Bill Bowerman, Nike’s co-founder and then Oregon track and field coach, is cooking something with his trusty waffle iron. However, if you were to taste what Bowerman was crafting, chances are you would not be asking for seconds. That’s because he was using a crude mixture of urethane (a rubber like material) to construct the sole of a new shoe he dubbed the “Moon Shoe.” Bowerman believed that a shoe that mimicked the grid-like shape of a waffle iron would provide greater traction for the user, and though seemingly outrageous, he was right. These waffle racers were donned by American distance running legend and pioneer, Steve Prefontaine, during several of his victorious feats. Additionally, they were the first shoe produced by Nike, now a multibillion dollar sneaker company. 

To the relief of runners worldwide, we’ve come a long way from Moon Shoes. Advances in running shoe technology include the implementation EVA (Ethylene Vinyl Acetate) foam to construct the midsole (which is important for the energy return of a given shoe), shock-absorbing insoles (which aid in injury prevention), and the use of actual spiked shoes to increase traction as opposed to a grid-patterned sole. Generally, these advancements have been embraced by the running community; however, a recent adaptation has sparked quite the controversy. 

In 2016, Nike created the “Vaporfly,” which used PEBAX (Polyetheramide elastomer) foam and a carbon plate instead of an EVA foam-based midsole. Effectively, the PEBAX polymer offers greater energy return than its EVA counterpart, and the carbon plate induces substantial rigidity, ultimately resulting in a spring-like effect with each passing stride. If all of this shoe-science jargon is more than what you bargained for and you’re more interested in the results of these implementations, I’d encourage you to keep reading! 

The Nike Vaporfly (or some carbon-plated Vaporfly adjacent) has been behind essentially every major road-race victory since 2016. In fact, Eliud Kipochoge, often regarded as the greatest distance runner of all time, clad a pair of the Vaporflies during his Earth-shattering sub 2-hour marathon effort. Moreover, the ZoomX Dragonfly spikes are becoming quite popular in the sport of track and field. They’re distinct from the Vaporflies because they are an ultralight-weight spike, while the Vaporflies are more similar to a traditional running shoe. Also, the Dragonflies lack a carbon fiber plate, but still contain the PEBAX foam. 

Given the biomechanical advantage that these PEBAX-based shoes offer, some members of the running community have had adverse reactions to them. For example, former American marathon record-holder Ryan Hall has expressed his distaste for the supershoes over social media, claiming that they disturb the authenticity of the sport, as there will be a discrepancy between “supershoe races” and “non-supershoe races.” Former marathon world record holder Tegla Loroupe of Kenya explained this controversy well; she claimed that by using super-shoes, “You are cheating, you are not a hero because you don’t use your own strength…You can have a faster shoe, but what about those who can’t afford them, it’s almost like doping, to me there is no difference between doping and having a faster shoe.” 

Loroupe certainly raises some valid points; the PEBAX polymer offers roughly 30% more return than EVA. Also, they are much more expensive than the average running shoe, which is around $100, costing upwards of several hundred dollars. 

At its crux, the PEBAX problem boils down to the age-old question: are advances in technology completely beneficial, or do they propel humanity further away from the sanctity of nature and all that is natural? 

As someone who owns both a pair of Vaporflies and Dragonflies, I will concede in saying that they are faster than any shoe I have ever worn before. However, the improvement is marginal; modifications in training, diet, sleep, running economy, etc., are far more important to racing success than any springy running shoe. Despite this, at the elite level, runners will take any marginal improvement they can get. Thus, until made reasonably accessible to every runner, perhaps the most pressing concern with super-shoes is that they offer an inequitable advantage to their owners.