Why nobody ranks the top speed
The one number your watch shows big — the maximum instantaneous value — is the least reliable of all. GPS measures speed via the Doppler shift of the satellite signal, and a single reading can spike from shading, a flick of the wrist or spray on the case. That is why every serious speed discipline ranks averages over a duration or a distance: a half-second outlier disappears in the average, but the run still has to be ridden. The standard is the best 2-second average — short enough to reward one perfect run, long enough to filter measurement noise.
The disciplines: 2 s, 30 s, 500 m, nautical mile, alpha
The abbreviations ask different questions of the same run: the 2 s average measures the peak moment, the 30 s average whether you can hold the pace. 500 m and the nautical mile (1852 m) are the classic distance disciplines of speedsurfing — here the whole run counts, not the moment. Alpha 500 demands 500 m with a gybe in the middle, measuring what a slalom sailor can actually do. And avg 5×10 (the average of your five best 10-second runs, non-overlapping) rewards the consistent session over the one lucky hit.
Which watch is good enough? Almost any.
You no longer need a dedicated logger for solid numbers. A Garmin with our free Connect IQ app computes the disciplines on the watch and uploads the session automatically. A Polar connects via your account. And every other GPS watch or phone app — Apple Watch, Suunto, COROS, Garmin Connect, Strava — exports a FIT, GPX or TCX file from which all values can be computed. More important than the brand is the recording rate: one point per second is the basis for clean 2 s values. “Smart recording”, which stores a point only every few seconds, throws peaks away.
Why two devices show different numbers
The usual suspicion — “my watch is wrong” — mostly has a more innocent explanation: two devices do not measure the same thing. Speed comes from the Doppler signal and is very reliable even at low pace; distance, however, is sometimes summed from positions and sometimes integrated from speed — and the two drift apart. We measured it: the same session came out at 4.78 or 5.38 km depending on the method, eleven percent apart, both devices “correct”. Add presentation: a thinned track (one point every 10 s) cuts corners and systematically under-measures. If you compare numbers, compare the method — or use a platform that computes them the same way for everyone.
How do you spot a bogus number?
Three contradictions give it away: a 2 s value below the 30 s value (impossible — the shorter window always wins). A session average above the peak (impossible). Or a track that never touches water. A fair ranking checks exactly this automatically — we call it the trust score: implausible sessions drop out of the ranking, and the rider affected sees the reason. The leaderboard stays credible without anyone censoring by hand.
Frequently asked questions
Which GPS tracking app for windsurfing is free?
MyWaterSessions is completely free — tracking, per-spot rankings, session analysis and wind forecast, with no premium tier and no paywall. The Garmin watch app is free as well, and files from any other watch (FIT/GPX/TCX) can be uploaded at no cost.
Does GPS tracking for windsurfing work without a Garmin?
Yes. Any GPS watch or phone app that exports FIT, GPX or TCX works — Apple Watch, Suunto, COROS, Polar (also automatically via account link) or an export from Garmin Connect or Strava.
Why does my watch show a different distance than the analysis?
Because distance is computed two ways: from the GPS positions, or by summing up speed. The two can differ by around ten percent — especially at slow pace. The positions are the more reliable method.
What is a good windsurfing speed?
Planing starts around 15–20 km/h depending on gear. Ambitious freeriders reach 50–60 km/h as a 2-second average, slalom and speed sailors considerably more — the 500 m world record is above 98 km/h. More meaningful than any absolute number is the ranking at your own spot in comparable wind.
Is a phone enough instead of a watch?
For a logbook, yes; for speed measurement only partly: a phone usually sits in neoprene or a dry bag, damps the GPS signal and often records only every few seconds. A watch on the wrist recording once per second delivers the cleaner peaks.