I feel like the word metabolism is often misunderstood. My metabolism is just the number of calories I need to maintain my weight. If I start being more active

I feel like the word metabolism is often misunderstood. My metabolism is just the number of calories I need to maintain my weight. If I start being more active my metabolism increases, if I become less active it decreases. So, metabolism is really just an expression of how active we are. Some athletes eat 5-10,000 calories a day just to maintain their weight. Hard working laborers also need a lot more calories than office workers. Meanwhile, people blame their metabolism as if it's just a trait they can't control like their height. You absolutely can increase your metabolism, just move more. This is also likely a big reason why many people gain weight in adulthood - in school we have weekly gym classes and we spend lots of time running around ad playing with friends etc. Then we grow up and our activity level plummets, but we don't adjust our diet to accommodate our much lower metabolism.