Nike Vaporfly and Tokyo 2020 Olympics controversy

These "super shoes" became the focus of claims that they were a form of technology doping and that they provided athletes an unfair advantage.

[2] On January 31, 2020, World Athletics, the governing body for professional track and field,[3] issued new guidelines concerning shoes to be used in the upcoming Tokyo 2020 Olympics.

Competitors of Nike rushed to bring new running shoes to market in time to meet the new guidelines so their sponsored athletes had a chance to compete in the Tokyo 2020 Olympics and for these companies to show off their products in one of the most watched sporting events in the world.

[6] In the middle of the ZoomX foam there is a full-length carbon fiber plate "designed to generate extra spring in every step".

[10] Each are designed to be slightly faster than the previous model with a lighter weight and cutting more from outsole rubber to increase the amount of ZoomX foam while staying under the 40mm height stack guidelines.

It's this combination of the bouncy foam and the carbon fiber plate that result in the reduction in effort and increased speed.

Expert sports technologist Bryce Dyer attributes this to the ZoomX and carbon fiber plate since it absorbs the energy and "springs runners forward".

[6] This is similar to the LZR Racer swimsuit controversy from 2008: prior to new regulations being put in place, users of both products broke records while other competitors could not keep up.