Every season there's a new way to go faster. A shoe, a powder, a protocol, a number your watch has suddenly decided you should care about. Some of it does something. A lot of it has never really been tested. So we go and find out — including the times the answer is boring.
Everything on this site is either something to read or something to use. The reading comes in two kinds — a promise put through the wringer, or an explainer that hands you the machinery underneath — and every piece says on the front which one it is. The rest is calculators you can run yourself. No training plans, nothing about your knee — we're not your coach and definitely not your doctor.
"4% faster." "8 watts." "Recovered by morning." We take these one by one, read what has actually been measured, and write down plainly what came out of it. Next to those, the explainers: VO2max, thresholds, fuelling, heat, why you slow down. Filter by sport, topic or kind.
Browse the library →Pace converter, race predictor, heart-rate zones, climb times for the famous cols, an aero lab. Free, no login — and every tool says out loud where it bends, because that's kind of our whole thing.
Open the tools →Carbon-plated shoes make you 4% faster.
It's done → read the full write-up: the numbers, the caveats, and who it is for.
Explainer. A sports watch measures a handful of things and works out the rest: which numbers come from a sensor, which from a model, and which from a guess about you.
Read the explainer →Explainer. What the number measures, the three routes to a value, and how far a watch estimate can be off on you personally.
Read the explainer →Check. The famous number is 4%. Across fourteen studies the average is closer to 2.75%, and nearly all of it was measured on flat ground.
Read the check →Explainer. Seven questions that tell you how far a study travels: who was in it, how many, how long, compared with what, and would it have been published anyway.
Read the explainer →The six calculators, each showing its formula and where it stops being reliable: race pace · race-time predictor · heart-rate zones · climb times · aero watts · VO2max estimate.
Endurance media runs on gear. Test shoes that never go back, affiliate links, launch embargoes, a long weekend in Girona. It's not that those writers are liars — it's that you can never quite tell where the opinion ends and the arrangement begins.
So there's no arrangement. If a shoe is a marginal gain dressed up as a revolution, saying so costs us nothing.
One vote, no account — your browser just remembers you've voted. Whatever wins moves to the front of the queue; the full list lives on the library.
One thing at a time, dug into properly, reasoning out in the open. No schedule to keep up with, no filler. You can see what's in the queue right now.
No spam, we don't sell your address, and you can leave whenever you like.