Hold your hand out in front of you and look at it. Move the palm up, then down, and around. Then rotate it slowly from one side to the other. Read more http://achim.org/muscles/

2. MUSCLES

3. Hold your hand out in front of you and look at it. Move the
palm up, then down, and around. Then rotate it slowly from
one side to the other. There is hardly a movement that you
cannot do with it. Notice that those motions involve your
forearm and upper arm. From your shoulder down, all the
muscles and bones are working together with your hand as it
undergoes various movements. Place your left hand on your
right hand, as you move the right hand. Feel the bones and
muscles beneath the skin responding to the messages sent
from your mind. Look at your hand carefully as you move your
fingers in every possible way. Do it again, but this time with
your other hand on your wrist, and then your forearm. Rotate
your hand again, with your other hand on the forearm bones.
Feel the radius and ulna bones turning over on one another as
you do it.

4. Now, within your shoes, wiggle your toes.
Stand up and, with your hands on your hips, slowly walk
across the room. As you go feel the bones and muscles
moving in perfect coordination. Notice how your legs and
body do what is needed to keep you balanced as you walk.
What is this amazing machine called the human body! It is
astounding!
Your muscles are attached to your bones at exactly the right
places where they will give the best leverage. That took
thinking! Downstairs in your family workshop, make a couple
bones and several muscles, ligaments, tendons, and all the
rest, and then figure out the best place to locate the ends of
the muscles in order to obtain the best leverage. Oh, you say,
you don’t know how to make a muscle! Well, no one else can
either. That which intelligent human beings cannot do,
random actions of molecules are supposed to have
accomplished.