It seems like there is data missing for "runnig workouts" / "interval runs" in the Fitbit statistics.
When I remember correct there was a section on the bottom about the "Intervall splits".
I think it was called "Workout summary".
I found an old screenshot "fitbit-workout-summary-interal-run-present-but-broken.jpeg" of about a month ago.
There the functionality is broken - but the visualisation present.
This data is now missing.
I attached a screenshot "fitbit-workout-summary-interval-run-not-present.jpeg" that shows that the data is missing.
Furthermore this split data can also be visualized in Strava.
Currently this is also not the case. It looks like a regular run on Strava.
But I am not sure if this ever worked in combination Fitbit+Strava.
Other brands seem to use this capability of Strava.
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