I run ~ 8 hours per week (w/ GPS but no Glonass). I do not use navigation.
I ride/run an average of about 7 hours a week (all gps) with every second recording, glonass off, phone notifications w/ vibration on, a daily alarm I can't change thanks to Garmin, and backlight set to come on with button push, Third party watch face with seconds counting on the screen all the time, etc. I usually bank on having to charge mine once a week when it gets to about 25%