Yup. Twice I have done 12 hours of pretty much solid walking, although some of it was pretty slow (fairly steep + around 11,500' and of course I had my pack) a

Yup. Twice I have done 12 hours of pretty much solid walking, although some of it was pretty slow (fairly steep + around 11,500' and of course I had my pack) and my Fitbit says I haven't broken 50k. I gathered nothing, stopped only to eat or because I had to catch my breath (5000' of climb).