Hey TC ? I think it's possible but probably more difficult. There's a VERY interesting character out there by the name of Art Devany, who's 68 years old, 6-ft 205, about 7% fat, who can slam dunk a basketball. He's also a scientist. Here's his take on the question, should be good food for thought:
Thermodynamics and Muscle
In an earlier post on Mass I made the point that one can build muscle without being in positive caloric balance. I didn't claim that is the best way to gain muscle, but I think it is the best way to change your body composition to make a leaner and more muscular body. If you want to grow beyond that point, then a slight caloric excess is all that is required.
The problem is that most people have no idea what their energy expenditures are or what their intake is. Nor do I. So, in accordance with the rule athletes and body builders tend to follow "If a little is good, then a lot is even better", people eat too much trying to put on muscle. Most body builders I have seen over many years are too fat. Even pros may get smooth in the off season. And most of the young men I see these days in my gym who are body building are way too smooth.
Here is the most direct evidence you can find, better than some lab study. What do most people who eat more than they expend look like? We call them fat. Excess energy goes into fat after the muscle glycogen is restored (a trivial amount). Eating more protein doesn't mean that protein is what you get when the body is through with it. A lot of it will go into fat.
The hard thing is to gain muscle mass and maintain or improve your body composition as you do so. That is why it is important not to overeat on a long term basis.
Protein pools in the body are excreted as they turn over. The protein pool varies and its size is affected by protein intake, by cell turnover and loss, and by nutrient partitioning into body protein or fat. It has a lot of places to go and you certainly need plenty of it. It does not violate thermodynamic equilbrium to gain muscle as you lose fat. Working out and fasting promote GH which is protein sparing and directs resources to repair and maintenence. You have plenty of fat to fuel this process, even those of use who are lean have enough.
But, what about thermodynamic equilibrium?
We are always in it. You can't violate the laws of thermodynamics, whether you eat too much or too little. If you take in excess energy, you store the excess. The energy is still there and none is lost or destroyed. As you gain mass your energy expenditure rises. You continue to gain mass until you reach a fixed point body mass where intake and expenditure are equal again. No laws of thermodynamics are violated. But, you sure look bad at your new equilibrium state because a lot of the gain will be fat.
It takes a while to get there though. And much depends on how much excess energy goes into fat or muscle. You don't need a whole lot more muscle to burn the excess intake, but you need quite a lot of fat to carry around before your expenditures equal your intake. So, if you work out you will tend to partition the nutrients into more muscle than fat.
You do have to worry that continuous caloric excess brings other adaptations; you lose insulin sensitivity, which tends to shift nitrogen retention toward fat rather than muscle, you hit your liver with a lot of nitrogen or ammonia and it starts to adapt in ways not yet understood but can't be good. A lot of other things happen too. Long exposure to caloric excess is bound to affect many metabolic and thermoregulatory functions. It has to mess up your appetite. And to overeat systematically you can't eat enough bulk or roughage, you must eat calorically dense foods which we know to be unhealthful. Had enough? There is more I don't have time to think about.
Our human species never lived in a state of chronic excess caloric intake. Do you want to go against the adaptations that evolved in the long course of human life?
Suppose you continue to stay in excess caloric balance. Your body mass must continue to grow. You must then eat even more. But if you are always in excess as your mass increases, then you have to become fat and eventually obese.
Obesity is implied by the laws of thermodynamics; constant excess intake over a long period of time has only one equilibrium --- gross obesity. You can see it all around you.
I do agree that if you are going to gain muscle, you need protein in excess of what is required for maintenance and to cover losses. One way to do this is to burn fat, with favorable effects on your body composition. This takes GH from a hard work out or from fasting.
Another way to do this is to eat less carbohydrate (which some claim to be "protein-sparing" when it is not). Carbs release insulin and generate a mild shock to the body when glucose rises. The sugar is toxic and the body works hard to sequester and burn it. So, it doesn't burn fat. As your body becomes a carb burning machine, it burns less fat. When the sugar is gone from your blood stream, there is only one way to produce it: gluconeogenesis, the making of sugar from muscle protein. High carbs are muscle wasting, not protein sparing after you take first and second order effects into account.
The best way to do it is to alternate excess protein consumption with light fasting. Of course, you must work out as well. Intermittent excess protein intake is perfectly consistent with our evolutionary past and that is enough to put on plenty of muscle. Too much protein is toxic. Intermittency is protective because it lets you diversify your toxins (everything is economics).