Race autopsy

Drop in one race file — a .fit, or the .zip Garmin hands you. You get the race run again, segment by segment, against the 47,998 marathon finishers who came in around the time you did — and a named cause, or an honest gap where there is not one.

This is the one number a race file cannot contain: one race cannot establish a threshold. Given it, this page can measure how long you spent above it — which is the only thing here that can tell an over-paced race from an ordinary one. It is treated as stated, not measured, and every sentence resting on it says so.

A maximum heart rate will not do, and that is a measurement rather than a preference: a threshold sits somewhere between 85% and 92% of a maximum, which is about 14 beats at a max of 200 — wide enough to move this answer from most of the first half to almost none of it.

Without a training block behind it, five of the twelve failure modes cannot be tested and the page says which. Nothing is scored as absent.