The cessation of the pumping of the heart

Cardiac Arrest is the cessation of the pumping of the heart.

This will resulted in a sudden stop of effective blood circulation and make your body doesn't get enough oxygen supply that could lead to death if not given an immediate treatment

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.