Muscle is one of the major components of human body. There are more than 650 muscles in our body. In fact, muscles amounts to approximately half of the total body weight of a human.
Muscles are made of fibers. These fibers provide flexibility (enable muscle to lengthen and shorten) and help the body in producing movements. Muscles are connected to bones with tendons.
Based on the functions these muscles perform and their location in the body muscles are classified in various categories. Skeletal muscles, smooth muscles and cardiac muscles are three main categories of muscles. Succeeding paragraphs will provide you brief description about each type of muscles.
- Skeletal Muscles : Skeletal muscles are also called as striated muscles. The main function of these muscles is to regulate bone movements. Presence of these muscles can be seen and felt. Tendons attach the skeletal muscles to bones. Skeletal muscles always come in pairs. The first one ensures bone movement in one direction while the other moves the bone in its original place-the other way. As you can move these muscles as per your wish through the nervous system, these muscles are called voluntary muscles. Skeletal muscles are capable of performing two forms of contractions – first the twitch (short single contractions) and the other one tetanus (long, sustained contraction).
- Smooth Muscles : These types of muscles are found in the internal body organs such as blood vessels, airways, digestive system, uterus and bladder. These muscles are capable of stretching and maintaining the tension of prolonged periods. These muscles have their own way of functioning. You do not have control over their movements and hence are known as involuntary muscles. They function at their own and you need not to issue any directions through your nervous system for their movements.
- Cardiac Muscles : These muscles are present only in the heart. As is known, heart functions without any directions from the nervous system. It is so because the heart muscles are involuntary in nature and have their own method of function. These muscles can stretch for limited time (just like smooth muscles do) and contract with the force of skeletal muscle. Cardiac muscles are twitch muscles (performing single short contraction).
Sprains, strains, charley horse (cramps) and repetitive stress injury are some of the most common forms of muscle injuries.
Muscles are important component of human body. Almost all actions of the body are regulated and controlled by muscles. Muscles provide shape and strength to our body. Important functions like breathing, blood circulation, digestion is performed by various organs only with the help of muscles.