- Edited
So, I have been leaving my right foot resting on the pedal at all times. I practice about one hour in a session, and I have never felt strain on that foot (ankle or heel) doing it that way.
I think I learned this somewhere (couldn't find the source now). I also doubt this is some kind of rigid rule. Experienced players probably would figure what works best from them on how to place that foot. On the other hand, I am not aware of any solid reason against doing so, which makes me wonder if this is a good habit to form early.
BTW The sustain pedal I have for my digital piano has fairly good resistance. And I have read that on acoustic piano it is possible to adjust the pedal tension so that just resting the full weight of the foot on the pedal (ankle on the floor of course) would not push it down.