Several years back, I trained this girl named Camille for an entire year. She was roughly 5’6” and 132lbs. She was already eating in a very healthy manner, so I told her to just keep eating the same way (around 1,600 calories and 110g protein per day).
Over the course of the year, her bodyweight never fluctuated more than a few pounds. She went from squatting 65lbs to 215lbs, deadlifting 65lbs to 275lbs, hip thrusting 95lbs to 365lbs, bench pressing 45lbs to 105lbs, and being able to perform 3 bodyweight chin-ups. Her physique improved markedly despite zero change in bodyweight, and she looked very lean and athletic. She put on her pants from before she started lifting, and there was a 4-inch gap in the waist, but the glute area was very tight.
When you recomp, you actually lose overall body volume because muscle takes up less space than fat at equal mass. Moreover, you add shape to the right areas and whittle off shape from the “problem” areas, which results in a much more aesthetically pleasing appearance.
This is what happens with many of my clients, and every few months, their body composition and physique improves. Obviously, if an individual is markedly overweight or underweight, they will be placed on a calorie deficit or surplus, respectively. But many can simply keep their calories the same (though typically increasing protein intake) while utilizing progressive overload on a variety of lifts in a variety of rep ranges, thus becoming stronger and fitter. I’ve demonstrated this over and over, even with advanced lifters (see my post on Nikki from November 26, 2018).
Bulking and cutting is a popular strategy. However, you do not always have to increase your calories to gain muscle, nor do you always have to decrease calories to lose fat. You can maintain caloric intake while training like a beast (recomping). It’s important to know about this option so you’re not under the false idea that you have to be fluctuating drastically in bodyweight to improve your body composition. You can also “gaintain” by eating at a very slight surplus and moving up in weight gradually over time, for example gaining 1-3 lbs/yr.