In this episode, we unpack why lactate threshold is one of the most useful predictors of ultra performance, not because you race at threshold, but because it sets the ceiling for what “sustainable” feels like for hours. A higher threshold means your steady effort costs less energy, surges hurt less, and you drift into the red less often on climbs, headwinds, heat, and technical sections. You’ll learn a simple mental model (threshold = your red line), the three most common training mistakes (turning threshold into a weekly race, using wrong zones, living in the grey zone), and a practical weekly approach: one controlled threshold session, lots of truly easy running, plus durability work to hold effort late in long runs. The key takeaway: raise your threshold, and your “easy” pace gets faster, that’s real ultra performance.

Motivation is a mood, it comes and goes. Consistency is a system, it keeps you training even when life gets messy. This episode explains why relying on “feeling like it” leads to stop-start training, and why the runners who improve most are the ones who reduce friction, pre-decide their sessions, and protect a minimum standard on low-energy days. You’ll learn practical tools like a “minimum viable run” (short, easy, just show up), “if–then” plans for busy or bad-weather days, and simple habits that make starting easier.

The key takeaway: don’t build your plan for your best days, build it for your worst week.

VO₂max measures your maximum aerobic capacity, but ultra races are not performed anywhere near that intensity. What decides performance is not how big your “engine” is, but how efficiently and sustainably you can use it for many hours.

Ultra success depends on factors like lactate threshold, aerobic efficiency, fueling tolerance, muscular durability (especially for long descents), and disciplined pacing. Chasing VO₂max through frequent high-intensity sessions often adds fatigue without improving race-day performance.

Instead, effective ultra training prioritises sub-threshold work, long aerobic sessions, strength for resilience, and practicing nutrition under load. In ultras, the winners aren’t the runners who can go the hardest. They’re the ones who slow down the least.

Intensity can drive quick improvements in trail running performance but only for a short time. Hard sessions create a strong training signal, yet they also generate fatigue faster than they build fitness. At first, fitness gains are visible; over time, accumulated fatigue masks those gains, leaving runners feeling heavy, flat, and slower despite training harder.

The mistake many runners make is responding to this fatigue by adding even more intensity or letting easy runs drift too hard. Instead, sustainable progress comes from using intensity sparingly, building a strong aerobic base, and allowing recovery to keep pace with training stress.

Key message: intensity should support training, not dominate it.

Rule of thumb: If intensity is always the solution, it eventually becomes the problem.

Most ultra runners don’t lose races on the climbs—they lose them on the descents.

In this episode of The Trail Running Briefing, we break down why downhill running causes so much damage despite feeling easy at the time. You’ll learn how eccentric muscle loading silently destroys the quads, why this fatigue is delayed and deceptive, and why cardiovascular fitness alone won’t protect you late in an ultra.

We also cover the most common mistakes runners make in training avoiding downhills, underestimating their impact, and treating them as free speed and what actually works instead. From smarter downhill exposure to eccentric strength work and technique adjustments, this episode gives you a simple mental model to understand why so many races fall apart after the halfway point.

Key takeaway: If you don’t train your quads for the downhills, the race will.

Understand your training. Run better.

This episode explores a common frustration among runners: increasing training volume or intensity, yet feeling slower, heavier, and less fit. The key message is simple, fitness doesn’t come from training itself, but from recovering from training.

Using a clear mental model, the episode explains how training creates fatigue, and recovery is what allows adaptation and improvement. When training load increases without a matching increase in recovery, the body never fully adapts, leading to declining performance despite more effort.

The briefing highlights common mistakes runners make—adding more sessions, more vert, or more intensity—while neglecting sleep, fueling, truly easy runs, and recovery weeks. It then reframes recovery as an essential part of training, not an optional extra.

The episode ends with a memorable rule of thumb: You don’t get fitter by doing more. You get fitter by absorbing what you do.