What happened?
Summary
A 1h50m road cycling session was not auto-detected. No workout was created on the Workouts screen — not even a partial or generic one. The heart-rate data for the window is present and correct in the app, so this looks like a detection failure, not a sync or capture problem.
Environment
- App version:
- Install: <APK from Releases / TestFlight>
- Platform: <Android 15 / iOS 18.x, device model>
- Band: WHOOP 4.0, firmware
- Official WHOOP app: not installed / not opened since pairing
- Band worn continuously, no disconnect or re-pair during the window
The session
Recorded independently on a GPS bike computer with a power meter:
|
|
| Date |
31 Jul 2026 |
| Start |
04:48 local (UTC+3) |
| End |
~06:38 local |
| Duration |
1:50:25 |
| Distance |
50.67 km |
| Avg speed |
27.5 km/h |
| Avg power |
117 W |
| Ascent |
79 m |
What OpenStrap recorded
The Heart screen for the same day shows a clear sustained elevation matching that window:
- Baseline before the ride: ~45–50 bpm
- Sustained through the ride: ~100–140 bpm
- Peak: 157 bpm
- Sleeping HR that night: 44 bpm (so ~3.5x resting at peak)
Expected
A cycling or generic workout covering roughly 04:48–06:38, with the HR trace attached.
Actual
Workouts screen is empty for 31 Jul.
Evidence attached
Happy to send the SQLite export for that day privately if useful.
Possible causes (speculation, not diagnosis)
- Low arm movement. Road cycling holds the wrist near-static on the bars even at high cardiovascular load. If detection gates on accelerometer variance before considering HR, steady-state cycling would be a systematic blind spot rather than a one-off miss.
- Proximity to the sleep window. The ride started at 04:48, shortly after waking. If the sleep/wake boundary for the day extends past 04:48, or the detector suppresses candidate windows near it, that would explain the miss independently of (1).
Steps to reproduce
Can reproduce on demand — I ride this route regularly.
App version
0.9.21
Platform
Android (APK)
Phone model and OS version
Pixel 9 pro
Which band?
WHOOP 4.0
Screenshots
Quick checks
What happened?
Summary
A 1h50m road cycling session was not auto-detected. No workout was created on the Workouts screen — not even a partial or generic one. The heart-rate data for the window is present and correct in the app, so this looks like a detection failure, not a sync or capture problem.
Environment
The session
Recorded independently on a GPS bike computer with a power meter:
What OpenStrap recorded
The Heart screen for the same day shows a clear sustained elevation matching that window:
Expected
A cycling or generic workout covering roughly 04:48–06:38, with the HR trace attached.
Actual
Workouts screen is empty for 31 Jul.
Evidence attached
Happy to send the SQLite export for that day privately if useful.
Possible causes (speculation, not diagnosis)
Steps to reproduce
Can reproduce on demand — I ride this route regularly.
App version
0.9.21
Platform
Android (APK)
Phone model and OS version
Pixel 9 pro
Which band?
WHOOP 4.0
Screenshots
Quick checks