Try replacing some of the snacking with targeted, moderate intensity workouts that last from 5-10 minutes.
This sounds counterintuitive, but tasks that require you to stand or to sit still cause more fatigue when they aren't broken up with exercise because the exercise itself lowers "semi-resting" muscle tension and improves endurance.
Unfortunately, I canNOT make my muscles warm up enough to exercise first thing in the morning without risking injury. But prolonged standing after a short workout is WAY easier than before.
You may initially have more fatigue from simply being out of shape, but as your body adjusts, the muscular benefits don't decrease. Thank goodness!