Everything we're working through, in one place. There are two kinds. A check takes one claim people keep repeating and puts it through the whole method — every source read twice, and two more readings that set out to break it. An explainer hands you the machinery underneath, so the next claim doesn't need checking by us before you can see it for what it is.
Carbs on the move: when, how much and which kind
The longer the effort, the more carbohydrate helps. Four sources give four ladders of grams per hour, and above about 90 grams nobody has yet shown a faster time.
Read the explainerFat, carbs and the fat-burning zone
You burn fat and carbohydrate at every effort. The share of fat is as high at rest as on the bike, the amount peaks at a moderate effort, and where that peak sits is different for everyone.
Read the explainerLab numbers, race numbers
A study finds four per cent. What reaches the finish line is usually less, and sometimes nothing at all — because part of the gap is arithmetic, part of it is that a capacity and a result are different things, and only the rest is the weather.
Read the explainerTraining zones, from scratch
Zones are agreements about how hard you are going, not laws of nature. What a zone is, why "zone 2" can mean three heart rates fifty beats apart, what each band contains, and how to find your own without a lab.
Read the explainerWhat your watch actually measures
A sports watch senses about four things and works out the rest. Which numbers come from a sensor, which from a formula, and which from a guess about you — heart rate, distance, calories, VO2max, training load, max heart rate, HRV and readiness.
Read the explainerVO2max: what it tells you (and what it doesn't)
A user's guide to the most-cited number in endurance sport: what it means, the three routes to a value, why two runners with the same VO2max can finish minutes apart, and what the mortality-tail actually says.
Read the explainerHow to read a training study
Seven questions that tell you how far a finding travels: who was in it, how many, how long, compared with what, what was measured, how big the difference was — and whether it would have been published if it had found nothing. No statistics needed.
Read the explainer“Carbon-plate shoes make you 4% faster.”
The famous 4% is now 2.75%, most of it never reaches your finishing time, and the plate turns out not to be the part doing the work — the shoe as a whole is. Read twice, by two people, against every source we could get hold of.
Read the deep-dive“Zone 2 is the base every engine needs.”
The most-repeated training advice of the decade. We'll look at what the polarised-training research really compared, whether the magic is the zone or simply the volume, and what happens if you have eight hours a week instead of twenty.
Why race-time predictors run fast
Almost every online predictor uses the same exponent. It is not the one its author gave for running, and for half of all marathon runners the prediction comes out ten minutes or more too quick.
Nothing in that corner yet.
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