#84 The Truth About Midsole Foams Pt. 2 (ft. Dr. Geoff Burns)

In the second of a two part podcast, Nate & Matt discuss the makeup of shoe foams with physiologist and researcher Dr. Geoff Burns. Dr. Burns takes us on a deep dive into the history, properties, and durability of common running shoe midole foams. Ever wondered what the difference between EVA, TPU, and PEBA is? Dr. Burns has the answers. Dr. Geoff Burns is a physiologist and engineer with an expertise in running. He works for the US Olympic and Paralympic Committee as a Sport Physiologist, and he conducts academic research with the University of Michigan. His work has focused on running biomechanics and performance. Geoff is a runner himself and competes internationally in ultramarathons. He was the 2016 USA national champion in the 100km and has finished 5th at the 100km World Championships, twice, in 2016 and 2018.  Chapters 0:00 - Intro 1:18 - The history of EVA and its properties 6:21 - TPU: a new foam on the scene 13:00 - PEBA: a revolutionary foam 20:24 - The confusing state of foams & marketing 24:14 - Supercritical foams 31:24 - Defining foam resilience & longevity 35:40 - Lab testing midsole foams 45:16 - Assessing foam durability 53:46 - Foam thermosensitivity 1:00:31 - Wrap-up