Creating an activity that only shows time in heart rate zones and duration

Can anyone give me some tips for creating an activity that only shows the duration of the current exercise as well as time in heart rate zones?

The closest I could get to that 'perfect' activity of mine, was when I added a data field from IQ that enabled me to show time in heart rate zones to a 'Cardio'-based custom actvity. However, calories burned as well as aerobic/anaerobic training effect is still shown - can I somehow remove these data?

I don't care that much about the training effect, but the calories really annoy me.... I already removed them from data fields shown during the exercise, but they are still being recorded and tracked in the app. I even tried to delete my weight from the watch, but it was somehow only removed from the Connect-app and not from the watch itself.