The functions of muscles are as follow:

  • It helps in the movement of the body.
  • It helps in the circulation of a blood throughout the body.
  • It helps in the digestions, respiration, and excretion of the body.
  • It helps to give the proper shape to the body.
  • It helps to store energy and produce heat to the body.

Voluntary muscles are the muscles which normally exist in the outer part of the body and controlled by an individual according to their will. When we make a movement of a body part it also moves according to our movement. The muscles of legs, hands, arms, neck, belly etc move together with bones.The voluntary muscles are thick and stronger in the middles part and thin and weaker in the ends of the parts. Such types of muscles are striated and stiffer.

Involuntary muscles are the muscles which cannot be moved according to our will and cannot be seen by the eyes. We cannot be controlled the involuntary muscles by our will. This types of muscles are softer and smooth then compared with voluntary muscles. The movement of the involuntary muscles is done by the nervous system of our body according to the requirement of a body, The muscles of kidney, digestive system, circulatory system etc have the involuntary muscles in our body.

Cardiac muscles are the muscles which are found only in the heart. These muscles are the involuntary muscles which are strong enough but are very flexible for extension and contraction. Cardiac muscles pump the blood so in this process huge amount of energy is needed. It takes the energy of our body and controlled by the nerve impulse. It is the most important muscles in the human body because if it stops working then human being left to breathe and die.