Plain-English explainers on the machinery underneath your training — the physiology, the numbers on your watch, the words coaches throw around. Nothing gets graded here; that's what the checks are for. This is the part that makes you harder to fool in the first place.
The first explainers are being written now. Here's what's on the drawing board — and if you'd read one of these tomorrow, tell us on X. The ones people actually want jump the queue.
How to read a training study without getting fooled
Eight untrained students, three weeks, a treadmill — and somehow a headline about you. The handful of things to look at in any study (who, how many, how long, compared to what) so the next big finding can't sneak past you.
VO2max: what it tells you — and what it really doesn't
The most famous number in endurance sport, and the most misread. Why two athletes with the same VO2max can be minutes apart, and why your watch's estimate is a different animal from the lab version.
Thresholds, explained like a human being
LT1, LT2, FTP, "tempo", "sweet spot" — five names for two bends in one curve. The three-zone map that quietly sits underneath every zone system, and how to find yours without a lab.
Running economy: the quiet number that beats VO2max
Two engines, same size, very different fuel bills. What economy actually is, why it separates racers with identical fitness — and which parts of it you can train.
Why summer runs feel broken: heat, humidity and pace
It's not fitness you lost in July — it's physics. What heat does to your heart rate and pace, how much slower is normal, and what the dew point tells you that temperature alone doesn't.
What your watch actually measures
HRV, "training load", VO2max estimates, recovery scores — some of it is measured, a lot of it is modelled. Where each number comes from, and which ones deserve your attention.
Carbs, fat and the crossover: how fuelling actually works
Your body runs on a blend, and the mix shifts with intensity. The crossover concept in plain words — and why "fat-burning zone" means less than the gym poster suggests.
Why you slow down: what actually breaks at the end of a race
Legs, fuel, heat, brain — the four ways a race falls apart, and the science on which one is really in charge. Featuring the long-running fight about whether your limits live in your muscles or your head.
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