Your muscles will not disappear in a puff of smoke after one missed meal. However, it is true that you're running on stored reserves while fasting.
I would say it's best to avoid being totally sedentary while fasting. But I'd also advise against doing strenuous exercise. One would think this is just common sense.
My experience is that a 1-day fast (only water allowed) has very little, if any, impact on the muscular mass. Anything longer than that does have some impact, but it's pretty slow to manifest. Again, common sense?
I would say it's best to avoid being totally sedentary while fasting. But I'd also advise against doing strenuous exercise. One would think this is just common sense.
My experience is that a 1-day fast (only water allowed) has very little, if any, impact on the muscular mass. Anything longer than that does have some impact, but it's pretty slow to manifest. Again, common sense?