That could just as easily be achieved by the method of locally recording on the SD card GP mentioned above without uploading who-knows-what about the device, your body, maybe even the surrounding area and other people to who-the-fuck-knows-where.

It can equally easily be recording exactly all of that data into some encrypted format on the SD card, which then gets uploaded to the manufacturer when opened with the proprietary application necessary to view the data.

The only difference is the choice over exactly when the data is uploaded, which in the US with its insurance system, results in no choice at all.

You mean "want". I'm sure if we let them, they'd try to convince us they also "need" to monitor our diet and exercise (and whatever else would incidentally be recorded) to make sure we're following doctor's recommendations on that.