Top 5 Science-Backed Reasons Runners DNF – And How to Prevent Them

GI distress. Muscle damage. Hyponatremia. Mental fatigue. Bad pacing. In this evidence-packed episode, we break down the five most common scientific causes of DNF (Did Not Finish) in ultramarathons—and how better training can help you avoid them.Whether you're training for your first 50K or aiming to shave time off a hundred-miler, this episode covers actionable strategies to improve your fueling, hydration, strength, mindset, and race-day decisions.🎙️ In this episode, Coach Zoë and TJ cover:The real reason most runners DNF—and it’s not bad luckHow to train your gut (and brain) for ultra successWhat "lifting heavy" means for runners (and what it doesn’t mean)Why tracking calories burned is NOT hotHow to stop sabotaging your race with early pacing errors⏱️ TIMESTAMPS00:00 – Pre-wedding chaos and podcast commitment06:40 – Hot or Not: Progression Runs, Pausing Your Watch, and Calorie Tracking22:19 – Strength Training: What "Heavy" Really Means for Runners38:30 – DNF Science Deep Dive: GI distress, muscle damage, electrolytes, mental fatigue, pacing01:18:10 – Why most DNFs = training errors, not race-day flukes📣 Subscribe so you never miss an episode💻 Learn more about coaching: https://www.microcosm-coaching.com📸 Follow us: https://www.instagram.com/microcosmcoaching