Last weekend’s extraordinary marathon performances — 1 hour 59 minutes 40 seconds by Eliud Kipchoge in Vienna and 2:14:04 by Brigid Kosgei in Chicago — have focused attention on an already simmering question: Does the International Association of Athletics Federations need a more stringent rule to define legal running shoes?

It appears that running, the original and most elemental of sports, now faces the same tradition vs. scientific innovation challenge that other sports have encountered. Think: tennis rackets, baseball bats and, perhaps most similar, competition swimwear — those polyurethane-based suits that were banned starting in 2010. The outcome of the current running-shoe debate could affect everything from stock prices of global footwear companies to who wins the Olympic marathon in Japan next summer.

Kipchoge, who became the first person to run the 26.2-mile distance in under two hours, and Kosgei, who set a women’s world record, raced in a revolutionary and bizarrely tall Nike shoe that has taken the marathon world by storm since 2016. In the last 13 months alone, male runners in the Nike shoes have recorded the five fastest marathon times ever. Other running-shoe companies are struggling to catch up, and may face patent hurdles.

The current I.A.A.F. rules state only that shoes may not confer an “unfair advantage” and must be “reasonably available” to all. The rule does not explain how these two values can be measured.