Autophagy is just cellular cleanup, your body breaks down all the junk cells (possible precancerous mutations, etc...) because it doesn't have to focus on digestion, this is the benefit of extended fasting or combining light exercise with intermittent fasting.I don't know this a word....yet.
What about if you want to build muscle?
If your goal is muscle you just do your workouts during your eating window so you have the energy to lift heavy.