The contractile organ that can be found and is part of the body structure of any human or animal is known as muscle.. The human body has approximately 650 muscles, which are made up of muscle tissue, that is, they are surrounded by a connective tissue membrane known as fascia.
The muscles They are the organs of greater adaptability that man has, that is, its content and form are modified more than any other. For example, a severe atrophy of one of these can be returned quietly and thanks to physical training.
According to their nature or origin, we find three types of muscles, the striatum or skeletal that make up 40% of the human body, the smooth or visceral and the cardiac, the latter two being the ones that occupy the least proportion in the body, around 10%.
Striated muscles make up the skeletal muscles of the body and are controlled by will. Its contraction turns out to be much faster than that of the smooth ones, for example and therefore they suffer much faster than these the effects of fatigue. The contractile unit of these is called the sarcomere and is made up of different bands and lines.
On the other hand, the smooth muscles, which bear this name because their fibers do not have striations unlike the predecessors, are those that form the walls of the viscera and are not under the dominion and control of the will. The contraction in this type of muscle is much longer lasting and its function is very important, since most of these are located in the gastrointestinal tract.
And the cardiac muscle, as its name already allows us to glimpse, is present only in the heart, being its striated and modified nature and involuntary control. Its contraction will be regulated by the Autonomous Nervous System.
Among the main functions of the muscles we find the following: provide joint stability, provide protection, help in maintaining posture, production of movement, generation of mechanical energy by the transformation of chemical energy, inform us about the physiological state of our body, for example, at the behest of renal colic, the pain suffered by the smooth muscle associated with this function will be very important, it gives the body a sense of posture and its position in space thanks to the nerve endings that the muscle tissue has , provides heat and stimulates blood and lymphatic vessels.
