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 luck
How to train your gut (and brain) for ultra success
What "lifting heavy" means for runners (and what it doesn’t mean)
Why tracking calories burned is NOT hot
How to stop sabotaging your race with early pacing errors

⏱️ TIMESTAMPS
00:00 – Pre-wedding chaos and podcast commitment
06:40 – Hot or Not: Progression Runs, Pausing Your Watch, and Calorie Tracking
22:19 – Strength Training: What "Heavy" Really Means for Runners
38:30 – DNF Science Deep Dive: GI distress, muscle damage, electrolytes, mental fatigue, pacing
01:18:10 – Why most DNFs = training errors, not race-day flukes

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

The MicroCast

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