Why Not Sneakers?

By Leo Kong' 21

Completing 26.2 miles in 1 hour 59 minutes 40 seconds, Kenyan Runner Eliud Kipochoge recently broke the 2-hour mark for a marathon. Although his personal effort and ability are undeniably outstanding, he has special support that helps him accomplish his goal: sneakers.

Recent news reveals that Nike has been working with this talented and hardworking athlete to help him break the 2-hour mark. Nike offered Kipochoge their Nike ZoomX Vaporfly Next%, which Nike claimed to be capable of letting the wearer experience “the ultimate energy return” and “the sensation of being propelled forward”. Such a feeling of running barefoot with extra springs at the bottom of the feet is partly what helped Kipochoge.

How on earth do these sneakers work to have such an impact on the performance of an athlete?

It turns out that the spectacular energy reservation comes from two factors: the foam in the midsole and the carbon fiber plate sandwiched inside. With the actual composition being the company’s secret, what can be told is that the foam is extremely light yet still very resilient and complaint. The squishy and springy aspects of the foam help absorb part of energy applied by the athlete’s feet to the pavement and returns a portion of it to the stride. Also, the carbon fiber plate helps stabilize the joints and reduce pressure on the calves of the athletes.

When running on the pavement for a marathon, the uneven ground exerts various forces from different directions that may increase the load on the joints and calves of the athlete, which slows them down and potentially wears their knees and ankles. Also, as the athletes are running, they cost a certain amount of energy to push themselves upwards and forward. However, only a portion of the energy is equivalent to the work they do when they are moving -- the rest is consumed by non-conservative forces like the friction between them and the ground, the force required to act against gravity as they land.

With the unique foam and carbon fiber plate, athletes are able to minimize the damage done to their joints and decrease the amount of energy that is wasted in the process of their running. More energy is absorbed by the foam and such conservative force helps the athlete to reduce the amount of work done by non-conservative forces.

With the prices of sneakers skyrocketing in recent days, more and more brands like Nike, Asics, and Adidas are working to help improve the performance of athletes and use their new technology to attract customers. As different types of sports emerge-- tennis, basketball, football, soccer, squash, wrestling, etc. -- different shoes appear, and each has distinct functions to provide more support, more grip, and more comfort. Wearing sneakers does more for you than make you look good. So why not sneakers?

Gonzalez, Robbie. "The Science Behind Nike's New, Even Faster Marathon Shoe." WIRED, 27 Apr. 2019, www.wired.com/story/the-science-behind-nikes-new-vaporfly-next-marathon-shoe/. Accessed 7 Dec. 2019.

Magically Energetic Foam. Nike, www.nike.com/zoomx. Accessed 7 Dec. 2019.

Nike Vaporfly 4%. Nike, www.nike.com/t/vaporfly-4-flyknit-running-shoe-v7G3FB. Accessed 7 Dec. 2019.