World Athletics (formerly the IAAF) released their updated regulations regarding footwear today. These regulations establish new rules governing the use of prototypes and impose immediate limits on sole thickness (i.e. stack height) and the use of carbon fiber plates.   In summary, it appears that the Nike prototype AlphaFly is now banned, but the Nike 4% and Next% are still legal. The AlphaFly was the Nike prototype worn by Eliud Kipchoge to break the 2-hour barrier in the marathon. In addition, competitors to Nike now have until April 30th to release their versions of the Next% in order for their athletes to wear new shoes at the Olympic Games in Japan. Otherwise, new shoes must comply with the new structural limits and be commercially available to all for a period of 4 months before they can be used in competition.   Ross Tucker from the Science of Sport joins Kara and Adam Goucher with Chris McClung moderating to provide our immediate reactions in this special episode. We discuss the practical implications of the new rules as well as where we believe they continue to fall short. Do these new rules resolve the great shoe debate or do they create more new questions than answers?