muscle

Can you recognize me?  I come in many shapes and sizes but there is not just one of me I’m just one of three.  Well actually not flavors but 3 different types. I pump blood in the heart, Move food along in the intestines and make you walk, move and run when attached to your bones. 
First, I am skeletal muscle.  I attach to your bones.  Well, I am saying is that I am not the only one doing the work; I have a twin.  Well not really a twin but a pair.  You see if I use force to go in one direction my pair goes in the opposite way. 
My brother the cardiac muscle is a real heart ache. He is always moody because he lives in a really cramped and small place, THE HEART.  I look up to him because his job is so important.  He is so flexible, he stretches in almost every direction.  Did I mention he is a real body builder too!  Some of his strongest features are endurance and consistency.

Lastly, my sister is smooth muscle.  She hangs out around the digestive system.  Unfortunately, she is so wild you have no control over her. You see she is involuntary that our parents control her, or as you call them Mr. and Mrs. Nervous system.  She can go long periods maintaining tension and stretching.