I have had my vivoactive 4s for almost 2 months. In that time I've only gotten one reading of VO2max after a run. I've gone on numerous walks and nothing has been recorded. It shows that it has been updated but I'm unable to see any change or open up more details about my reading. I mainly train indoors and feel I've gotten fitter but my reading is not showing anything. I've seen here that there have been issues with the vo2 max but I wonder if it had improved since then.