Learning about muscles is interesting because you learn how your body moves. Your muscles are very complex. You need muscles for almost everything you do. When you walk, talk, move your eye, and even sit, your body uses your muscles. Life would be almost impossible if you didn't have muscles.

Body Parts

There are different kinds of muscles in the head including the chewing muscles connected to the jaw. All of the neck muscles are wide and strong. The muscles in the body's middle are wide and flat. They allow the upper arm to turn and bend.

The gluteus maximus forms the seat of your body. This muscle allows people to walk. The thigh is made up of two groups called quadriceps and biceps. The most important muscle in the thigh is in the back. The muscles in the foot are small. The Achilles Tendon is tied to the heel by tissue.

The head muscle of the shoulder is the deltoid. This muscle makes extension movements. The group of muscles in front of the arm are the biceps and in the back is the triceps. The muscles of the lower arm control hands and fingers. These muscles help rotate the hand, and bend and straiten fingers. The muscles in the hand are short, so they are not as strong as the arm.


All muscles have the ability to expand or contract, meaning that they change their size. Most muscles cannot stretch very much. Individual cells cannot contract for very long. Muscles can stay contracted for a very long time. If muscles work too long lactic acid builds up. There are two ways to get rid of it. You can burn it as energy, or save it for energy. If muscles contract they contract all or none. Every muscle has a specific job such as pumping blood, helping to carry food, or helping with breathing.

Muscles work in many different ways. Smooth muscles have one nucleus deep inside it. Skeletal muscles look like eyeliner. It has many nuclei found outside fiber. Muscles are like a relay race, contractions of one group of cells take over when another group stops. After the muscle contracts it must have time to recover before it can contract again.

Most muscles are made up of long cells. The fiber in the cell can be one foot long but are thinner than a hair. Each fiber contains thousands of tiny strands. These strands contain protein. Muscle fibers are bound together by a sheath. Blood vessels supply food for fibers.

Body muscles support the skeleton. They make up fifty percent of your body's weight. There are over 640 individual skeletal muscles. They cover the skeleton in layers to give it shape. The muscle nearest to the skin is the superficial muscle. Usually muscles are named in Latin. Muscles under a microscope look like tiny threads. Muscles need energy to live. This energy comes from food. Each fiber has tiny structures called mitochondria. This is where glucose is turned into ATP. ATP provides energy so muscles can move. During the process some energy is lost. If you exercise the body produces too much heat and the heat turns into sweat.

Muscle Diseases

There are many different diseases and one of them is Lou Gerhig's. This disease hurts the nervous system and makes it hard for this system to send messages to the muscles. This makes the muscles powerless.

Muscles may hurt during or after exercising. This pain goes away in a day or two. To make sure your muscles are healthy you should exercise several times a week. You should also get enough rest.

Many muscle injuries are caused by overuse. Any sudden movement can cause a muscle to tear. This causes pain and can cause bleeding. It takes a lot of time for strains and tears to heal. You can treat these things by getting a lot of rest. To prevent your muscles from getting hurt you should warm up before you exercise.

Muscular dystrophy cannot be treated. This happens when muscles stop working.


Muscles are a big part of your body. It is important that everyone knows how to take care of them. I liked learning about how muscles need energy that comes from food. Muscles are a great part of your body, so keep them that way by eating and exercising right.


Houghton, Gillian. Muscles. New York: Rosen Publishing Group, 2007.

Silverstein, Alvin. The Muscular System. NewJersey: Englewood Cliffs, 1972.

Walker, Richards. Muscles. Connecticut: Grolier Education, 2006.

Walker, Richards. The Body Muscles. Connecticut: Grolier Education, 2004.

If this helped you, please tell me. I wrote it for a science report and want some feed back. Hopefully you learned at least a little from it.