Wearing Nike Vaporflys, Eliud Kipchoge ran a marathon under two hours.
There is no question that Kipchoge is a great athlete who has been dominating his sport for some time. However, the latest generation of Nike shoes he was wearing may have partly accounted for his extraordinary feat. The midsoles of the Vaporfly are designed to help athletes run more efficiently and cut their marathon times by 3 to 4%. To ensure fairness in competition, experts are reviewing whether shoe design should be subject to specific standards.
Video Spotlight: Is the Vaporfly for You?
This post is based on The New York Times article, Those Superfast Nike Shoes Are Creating a Problem, by A. Burfoot, October 19, 2019, and the YouTube video, Nike Vaporfly 4% Flyknit Review: Worth $250?, by Triathlon Taren, April 3, 2019. Image source: Shutterstock/Rocksweeper.
1. What design features make the Nike Vaporfly a superior shoe?
Guidance: The Nike Vaporflys have a thicker midsole which, with the right materials, produces more spring. The right materials are a special foam called Pebax and a carbon fiber plate. Pebax is extremely lightweight and delivers more energy return. The carbon fiber plate in the midsole also increases energy return and may improve foot function. Runners are less tired and feel more “spring” in their legs.
2. For this type of running shoe, what quality dimensions are order winners and order qualifiers?
Guidance: Student answers may vary, but performance, features, and perceived quality should be order winners. Elite marathoners would take aesthetics, conformance, durability (at least 150 miles – see video), and consistency for granted, making them order qualifiers.
3. What are the current I.A.A.F. rules regarding shoes? How should they be modified?
Guidance: The I.A.A.F. rules state that shoes should not give an “unfair advantage” and must be “reasonably available.” These rules are extremely vague. In the case of the Vaporfly, the patented design gives an advantage in terms of running performance. The patent also prevents other shoe manufacturers from adopting a similar design, thereby limiting availability to runners using other shoes. The rules should be more precise. They should define the notions of fairness and availability and provide standards with specific measurements.