The "Fourth Pillar" of Endurance Training: Durability Research

On October 1, 2026, a Canadian running magazine reported that sports scientists are studying "durability" (also called fatigue resistance), attempting to explain why athletes with similar values in the three traditional metrics—VO2 max, lactate threshold, and running economy—can differ so widely in performance on race day, and suggesting that durability may become the "fourth pillar" of endurance performance. That week, science journalist Alex Hutchinson discussed the latest developments in fatigue-resistance research on The Shakeout Podcast, covering what durability means, how it shows up in actual racing, and whether runners should make "improving durability" their top training priority. The topic is still at the research and discussion stage, and the report did not provide specific training conclusions.