How we analyze your ride
Your GPS track records where you went. Wind and equipment help us interpret what you were doing.
Reading your track
Foil Run looks for climbs, runs and turns in the route. You can open each one to see where it starts and ends, and how you rode it.
Your equipment helps put the movement in context. A parawing run, for example, can mix sailing, surfing and pumping.
What can GPS tell us?
Position and time let us measure speed and changes of direction. They cannot directly tell us what powered the movement. A fast, straight stretch might be sailing or a wave carrying you.
How we estimate wind
We start with weather near your ride or a saved wind direction. Weather models can miss local shifts on the water, so we use your climbs on both tacks to help refine the estimate.
We use the estimated direction to calculate sailing angles and VMG.
What if the wind shifted?
We look for changes in your sailing direction on both tacks, within and between climbs. If the headings on both tacks shift the same way, that can indicate a wind shift.
When there’s enough evidence, your angles and VMG use the estimated wind for that part of the ride.
How much should I trust it?
The estimate assumes you sail at roughly similar angles to the wind on port and starboard. If you point higher on one tack, perhaps because you don’t switch feet, the model can mistake that asymmetry for a different wind direction. That affects your angles and VMG too.
The numbers help you compare how you and your gear perform in similar conditions. Your technique and stance are part of the result.
If it disagrees with what you experienced, check the direction.
Is it the same as the Watch live VMG measurement?
The Watch calculates live VMG as you ride, using the data available at that moment. After the ride, track analysis uses a different algorithm with more powerful post-processing across the full recording. That’s why the final wind estimate and VMG can differ from what you saw on the Watch.
Peak speed · 5s
Your fastest five-second average across the recording.
Why might it be missing?
Gaps, sparse GPS points or apparent spikes can leave no reliable five-second window.
When something looks off
- The wind looks wrong
- Adjust wind for the whole session in Analyze, or open a climb or run to set its wind separately. Preview moves the map arrow; apply the change to update the results.
- A number is missing
- A dash means the measurement is unavailable. Missing wind or a gap in the recording can be the reason.
- The ride was different
- Open that part of the track and use Feedback to tell us what happened. A time or place helps us find it.