You can eat more than you think

The fear under this is that getting lean means a life of hunger. The opposite is closer to the truth, and the mechanism is worth getting exactly right because almost everyone gets it wrong.

Here's what's wrong with the popular version, the gym-bro pitch that “muscle is a furnace, every pound burns 50 calories a day at rest, so build muscle and eat whatever you want.” The classic per-tissue figures put skeletal muscle at about 6 calories per pound per day at rest, not 50. Build 10 pounds of muscle, which is a year-plus of serious work, and you add roughly 60 calories a day to your resting burn, about half a banana. The muscle furnace is a space heater, not a furnace.

So why does a lean, trained body genuinely get to eat more? Throughput, not resting rate. A trained person moves more energy through the system every day: the training burns calories, recovery has a cost, and there's simply more total mass to maintain. And the real unlock is nutrient partitioning. Resistance training is the most powerful partitioning tool there is: trained muscle has elevated GLUT4 transporters and 2-to-3-fold greater insulin-stimulated glucose uptake, so the calories you eat get shuttled preferentially into muscle and into refilling glycogen rather than into fat. A trained person also holds a bigger glycogen tank, so there's more room for the carbs you eat before any spillover toward fat storage.

The honest version in one line: a lean, trained body can eat more not because muscle idles like a furnace, but because it moves more energy through the day and sends the food it eats to better places. That precision, getting eat-more right where everyone else overclaims, is the whole point. (One caution: eat-more is the destination, not the method. You get lean on a modest deficit first.)