The Evolution of Training Technology with Hunter Allen

Steve House sits down with Hunter Allen — cycling coach, co-creator of TrainingPeaks, and co-author of Training and Racing with a Power Meter — for a wide-ranging conversation on training technology through the lens of the hype-adoption-disillusionment cycle. They trace the power meter's unusual "trickle-up" adoption (from data-driven amateurs to pros around 2008-2009) before working through today's landscape: HRV as a life-stress signal, the limits of wrist-based sleep tracking, the untapped promise of respiration and minute ventilation monitoring for mountain athletes, pulse oximetry's highly individual response to altitude exposure, heat/core-temperature training for hot events, skepticism around substrate utilization metrics, and the current bottlenecks holding back continuous lactate monitoring. The back half is a deep dive into continuous glucose monitors (CGMs), where Allen unpacks why endurance athletes run naturally higher glucose than the general population, why CGMs are both a performance and behavior-change tool, practical strategies like "food stacking" at meals, and why he recommends six months of wear time before drawing conclusions — closing with his take on where CGM technology is headed over the next decade.