Are the body's primary and immediate source of energy

Carbohydrates are the body's primary and immediate source of energy. The foods rich in carbohydrates are the ones responsible for fueling up our bodies further during exercise, and that's why it must be burned as we take a lot of it on a daily basis in order to use it well.

Well if you pick a machine to work on and that's gonna be your exercise if you don't stick to that machine your muscle strength your muscle mass rather will change because you haven't been doing it you change something in your exercise routine which changes your body's form of dealing with things for example you might become weaker or stronger depending on what kind of exercises you do in whether or not the machine you picked actually your muscles grow.