Without our muscles, we couldn’t move. We couldn’t eat, we couldn’t talk, we couldn’t even breathe. Our heart would not work because the heart is a muscle, too.
All of these things require a movement. We control some of the muscles but some just keep going, like the heart, or the breathing process. Our stomach would not be able to digest the food we eat.
Did you know there are three types of muscles? Watch this video from Khan Academy to learn more.