You have to use your Garmin device for recording the activities, if you want to have the metrics like Training Status, Training Readiness, Recovery Time, etc. updated. Alternatively you can use a 3rd party app supporting the update of this metrics to Garmin. Currently, Tacx (actually Garmin's native app), Zwift, Rouvy, TrainerRoad, and Concept2 are compatible.
I expected that; however, that is strange. During the activity, I have a watch on my wrist; therefore, increased HR is registered, which should impact "recovery time." I also import workouts manually, so there is information like power or HR in Garmin Connect.
During the activity, I have a watch on my wrist; therefore, increased HR is registered, which should impact "recovery time."
Only activities, where all the necessary metrics is processed in real time (HR, HRV, breathing rate, Calories expenditure pace, power, ...) impact the metrics. It means you must log the activity with your Garmin device, and have all sensors connected to it. Or use a compatible 3rd party app able to deliver the full data in the activity file.
I also import workouts manually, so there is information like power or HR in Garmin Connect.
The power alone is not sufficient. The activity file must include the full set of all data required for the calculation, and the app must be certified by Garmin, and synced automatically from the compatible 3rd party app, in order that the imported data gets reparsed by the device, which then reprocesses it and adjusts the Training Status.
Read more details here: What Is the Training Status Feature on My Garmin Device? | Garmin Customer Support
Faccio pesi e utilizzo al polso l'orologio, registra tutto e sono presenti tutte le metriche, recupero, training readiness , load, status ecc senza app di terze parti
It is easy to calculate; you have all the data from the workout plus constantly measuring heart rate. TrainingPeaks or Strava don't have a problem with different sources of activities and provide indicators across them. I don't suspect Garmin of intellectual laziness; this is kind of stupid policy, I think.