“But his bow abode in strength, and the arms of his hands were made strong by the hands of the mighty [God] of Jacob; (from thence [is] the shepherd, the stone of Israel:).” Genesis 49:24
Last month we learned about bones. We have bones in our arms and legs, but they cannot move and cannot make us move. Muscles supply movement. There are three types of muscles: skeletal, cardiac, and smooth. The body has about 700 skeletal muscles, comprising approximately 40 percent of our body weight. Thirty of these muscles are in our face, allowing us to smile, frown, and have many other expressions. Our Creator made cardiac (heart) muscle very strong so that our hearts would work for three-quarters of a century or more, resting only between beats. Smooth muscles, like cardiac muscles, are not attached to the skeleton and are found in blood vessels and in the digestive tract. The largest muscles are the gluteus maximus, located in each buttock. The smallest are the tiny arrector pili muscles that raise the hairs on your skin when you are cold.
Skeletal muscles are voluntary muscles. This means that we consciously will them to move. We wish to walk, or kick a ball, or turn the pages of this magazine and the muscles contract, making all of this and much, much more possible. Cardiac and smooth muscles are involuntary muscles. This is a really good idea, isn’t it? What if we had to consciously make our lungs expand and contract, even while sleeping? What if we had to will each beat of our heart, or control the movement of food through our digestive tracts? We could not do it! God is wondrous, maintaining every microscopic function of the body.
Could we live without muscles? One might think so. Do you have to have movement to live? That is the primary function of muscles, after all. Without them you would not be able to stand or walk or chew. But muscles do more than just move bones. Food makes its way through the body through the contraction of muscles. Otherwise you would chew your food and then be unable to swallow, and that would be the end of the food’s digestive journey! Think also of your blood. How does it flow to your head when you are standing? How does it flow to your feet when you are standing on your head? Why, muscles, of course. Breathing, speaking, and having the hairs rise on your arms when you are cold are all possible because of muscles.
Muscles work by pulling, never by pushing. Muscles contracting in pairs accomplish movement in multiple directions. Skeletal muscles are all attached to bones at each end of the muscles. For instance, the biceps muscle in your upper arm originates, or is attached, to the shoulder blade, and the other end is attached, or inserted, on the radius and ulna of the forearm, near the elbow. So imagine what happens when the muscle contracts, becoming shorter and fatter in appearance. If the biceps is attached to the shoulder and the forearm, what will happen? The elbow bends (the fulcrum of the lever) and the forearm is lifted.
Just like bones, muscles may be damaged. When someone says they have a “pulled” muscle, the muscle has been torn just like a bone may be broken. Our muscles are able to heal, although it takes longer than when our skin is damaged. Rest, fluids, and proper nutrition speed the healing process. Continuing to walk on a hurt leg, for instance, slows the healing process. Won’t it be wonderful in heaven when we don’t have to worry about injury anymore?
“Hast thou not known? hast thou not heard, [that] the everlasting God, the Lord, the Creator of the ends of the earth, fainteth not, neither is weary? [there is] no searching of his understanding. He giveth power to the faint; and to [them that have] no might he increaseth strength. Even the youths shall faint and be weary, and the young men shall utterly fall: But they that wait upon the Lord shall renew [their] strength; they shall mount up with wings as eagles; they shall run, and not be weary; [and] they shall walk, and not faint.” Isaiah 40:28–31.