I want to spend as much time fasting as possible. Could I still put on muscle by just allowing myself a 2-3 hour eating window?
Nutrition is not a black or white proposition. It is more like a rainbow of possible opportunities and pathways, at the end of which, as long as you get it right, a nice reward, or even a 6-pack awaits you!
Food is not a church, although many nutritional evangelists seem to want to get you down on your knees to pray and make believe it is. Foodstuffs are not inherently Good or Evil, at least not without a proper context. Nor is Nutrition a science. At least not yet. There are still too many unknown variables and shaky hypotheses, too few concrete theories. But one of these days it is likely to be a science, as the mechanisms of genes become more explicated and the genome superhighway gets better sign-postings.
Too many questions about nutrition are framed in a wrong-headed, black or white, back-to-front manner. Question like: “am I a ______________(good, bad, evil. unhealthy…you fill in the space) person because I had a beer last night”, “will I be damned and on the fast lane to Food Hell if I eat_________ (donuts, gummy bears or non-organic bananas, etc) ?” “or will I shrink down to the dimensions of a pencil-neck-geek if I don’t like to eat T-bone steaks at least 3 times-a-day?”
Human nutrition comes in all the colours of a rainbow. It has many if-and-&-but” sorts of questions which apply. A multitude of points need to be taken into consideration when trying to figure out a best-practice strategy of organizing things.
Back to the point, a simple answer to your question is, yes you can. But the question which might be better asked is “is this the most optimal, efficient & efficacious way to eat for the particular goal that I want to achieve?”
If the main goal is to get leaner, the answer is “yes”. If the main goal is putting on as much muscle as possible in the least amount of time, the answer then is “probably not.”
Genetics has a great deal to do with how you respond to various nutrients and eating patterns. The issue here is probably going to be the size of the feeding or meal that will be necessary. A day’s worth of proteins, carbs, and fats are going to have to be wolfed down at a rather high rate of speed in order to climb through the window of eating opportunity that you’ve drawn for yourself.
If the “Seldom but Big” meal pattern happens to work for you, great. But do ensure that it is working and that you’re not simply making believe something is working. Keep a record of things. And, should it turn out to work…
…the proof’s in the pudding.