Introduction to Muscular System:

Muscular System    Muscular System

The muscular system is the system of Human Body that provides motor power for all movements of body parts. The muscular system is composed of a special tissue called muscular tissue. Muscles have the ability to contract actively to provide the force for movements of body parts. Muscular system is an important system of human body because, without it, life will completely stop. Muscles produce not only those movements that are under the control of our will and that we can see and feel, but also those movements that are responsible for activities like breathing, digestion of food, pumping of blood etc.


Muscles are body tissues that provide the force for all body movements. They are made of special types of cells. For details of structure and types of muscles, please see the basic anatomy article

Types of muscles:

Muscles are basically of three types; Skeletal Muscles, Smooth Muscles, and Cardiac Muscles.
Skeletal Muscles:
Skeletal muscles form most of the human body weight. They are under the control of the human will and all body movements occurring by our will are produced by skeletal muscles. They are called skeletal muscles because they are almost always found attached to the skeleton and produce movements in different parts of the skeleton.
Smooth Muscles:
Smooth muscles form the soft body organs like stomach, intestine, blood vessels etc. They are not under the will of human beings and are responsible for unconscious body activities like digestion of food. They are called smooth muscles because when seen under the microscope, they do not have any striation in contrast to the other two types of muscles.
Cardiac Muscles:
Cardiac muscles are exclusively found in the human heart and nowhere else. They are extremely strong and powerful muscles. They are not under the control of human will and are involuntary. The pumping of blood by human heart is because of the force provided by the contraction of cardiac muscles.

Skeletal Muscle

Skeletal Muscle

Smooth Muscle (Stomach)

Smooth Muscle

Cardiac Muscle

Cardiac Muscle

Functions of Muscular System:

Muscular system has the following important functions in human body;

  1. MOVEMENTS OF BODY PARTS: Skeletal muscles are responsible for all voluntary movements of human body parts. They provide the force by contracting actively at the expense of energy. In other words, muscles are motors of body where chemical energy of food is converted into mechanical work.
  2. STABILITY AND POSTURE: Skeletal muscles stabilize human skeleton and give a proper posture to human beings. Some joints of human body are weak and they require the support of muscular system to achieve stability. Skeletal muscles are very important for such joints.
  3. HEAT PRODUCTION: A large share of the body’s energy is used by muscular system. As a result of high metabolic rate, muscles produce a great amount of heat in the body. Heat produced by muscles is very important in cold climates.
  4. CIRCULATION: Cardiac muscles provide the main force for the circulation of blood throughout human body. The regular pumping of heat keeps the blood in motion and nutrients are readily available to every tissue of human body.
  5. HELP IN  DIGESTION: Smooth muscles of organs like stomach and intestine help the digestive system in the process of digestion of food.

Muscular System Outline:

Components Muscles: Muscles are special type of tissues of human body that posess the ability of contraction and relaxation. They can contract actively thus producing force for different body movements.
Types of Muscle
Skeletal Muscle Striated, under voluntary control, found attached to the skeleton, produce major movements of body parts
Smooth Muscle Non striated, not under voluntary control, found in soft organs of body, responsible for processes like digestion of food etc.
Cardiac Muscle Striated, involuntary, present exclusively in heart, responsible for pumping activity of heart, very strong and tough
Functions Movements of body parts, Stability, and Posture, Heat production, Circulation, Help in Digestion