ontrack lab

Field notes & experiments.

The running data we collect, turned into things you can read, play with and scroll through. Some pieces you interact with; some you just read. More arrive over time.

01
field note24 Jun 2026

An atlas of ultrarunning

Where the sport lives, where it's fastest, and how a fringe pursuit became a global phenomenon — mapped across six decades and 27,000 races.

02
field note20 Jun 2026

When do ultrarunners actually peak?

Across more than two and a half million ultra finishes, the age at which ultramarathoners are fastest is far later than the track would have you believe — right around 40 — and the decline on the far side is gentler than almost anyone admits.

03
field note17 Jun 2026

The world's fastest marathon courses

532,375 finisher results, 14 marathons, and the 38,539 runners who raced more than one, used to settle which courses actually make you fast, and which only look that way because fast people show up.

04
field note17 Jun 2026

The world's hardest ultras

Using 6.8 million ultramarathon results, we separate a course's real difficulty from the runners who show up — and the famous monster, UTMB, turns out to sit in the middle of the pack, while Hardrock and a handful of savage sky-races top the list.

05
field note14 Jun 2026

Britain's fastest tracks

Using every result on OpenTrack, we separate a track's genuine speed from the athletes who happen to race there. The venue matters most over distance, and the 10,000m shows exactly how the method can be fooled.

06
field note11 Jun 2026

Five million GPS points

Every GPS point my Garmin has recorded since 2014, drawn as the places I run, with a live view you can zoom all the way down to a single sample.