heart rate monitoring during fitness+

When you use the Workout app, Apple Watch measures your heart rate continuously during the workout and for 3 minutes after the workout ends to determine a workout recovery rate. If you don't see your heart rate, check your settings. For more info, see:

Monitor your heart rate with Apple Watch - Apple Support

The first (and simplest) thing to try if something isn’t working right is to restart your Apple Watch and its paired iPhone. If necessary (device not responding), try a forced restart. Both methods can be found here:

How to restart your Apple Watch - Apple Support

Restart your iPhone - Apple Support

If that doesn't help, the next steps would be to unpair and pair your watch again and restore from the backup just created. This should result in no loss of data. It deletes all temp and corrupted files and re-indexes the file system.

Unpair and erase your Apple Watch - Apple Support

Set up your Apple Watch - Apple Support

I have the exactly same issue. Heart rate cannot track continuously when connected to fitness plus. If I open heart rate monitoring app or pause fitness plus, the measurement is restored. When I continue with fitness plus, it loses tracking again. When I work out alone without connecting to fitness+, there's no issue.

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