One consequence of newton's third law of motion is that

One consequence is that all actions have an equal and an opposite reaction. Look at it this way, if you punch a wall you will break your hand. The force that you apply to the wall is applied back to your hand so if you punch it hard enough you will break your hand. If you break through then it is still applied to you but it's not enough to stop you or hurt you.

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.