The muscles of the human body (the entire muscular system) are responsible for giving mobility to the body by connecting the nervous system with the bones of the skeleton. Being therefore the most important part of the motor system , its structure is very complex and can be divided into several classes according to the function they perform and their composition.
We will discover below what are the main muscles of the human body, where they are located and what functions they have .
- It may interest you: The 17 parts of the human body.
What are the muscles of the human body
The muscle is a contractile organ formed by skeletal tissue, blood vessels, tendons and nerves that allow its connection with the nervous system and its mobility . What allows the muscle to facilitate movement is its ability to contract and extend, which it performs through a complex physiological process.
The agonist muscles perform the contraction movement, at the same time that the antagonists extend. The synergist muscle collaborates with the main one in each movement, and the fixators immobilize the neighboring joints. Thus, in each action of our body, no matter how small, the muscles work in a perfectly coordinated way .
In addition to their most obvious function, that of facilitating movement, the muscles of the human body are transmitters of blood in the circulatory system and help the internal organs function.
How many muscles does the human body have?
The human body is made up of about 700 named muscles that make up 40% of our body structure. According to their structure and function we can distinguish three types of muscles: skeletal muscle tissue, visceral muscle and late muscle.
Skeletal muscle is known as voluntary muscle tissue because it consciously performs the contraction-extension movement. They are present in all actions and serve tomove the bones through the joints .
- To learn more: Skeletal muscle: what it is, types and functions.
The cardiac muscle is found only in the heart and is responsible for pumping blood throughout the body . It is considered an involuntary muscle because it does not perform the movement consciously.
Another type of muscle is the visceral muscle, so named because it is found in the viscera and has the function of, through contraction, sending substances to these organs . His movement is also unconscious.
20 muscles of the human body (and their location)
Next, we detail the muscles of the human body and their location. We also detail what function they perform:
1. Orbicularis oculi
It is a muscle of the face located in the eye socket that inserts into the orbicularis tendon to the tear duct.It is responsible for closing the eye and is activated when we laugh, producing the facial sensation of pleasant laughter.
2. Orbicularis lipis
It is a facial muscle located around the mouth and, in addition to being the one that allows the closing of the lips, it is also the one that facilitates the position of the mouth to kiss , for which it is also called “the kiss muscle.
It is a muscle of the head housed in the temporal cavity (sides of the skull). Its contraction allows the elevation of the lower jaw and its movement backwards , thus facilitating the chewing movement.
It is one of the main facilitating muscles of head movement. Located on both sides of the neck, it moves the craniovertebral joints producing chin elevation, lateral movements, and head rotation .
Tendinous muscle tissue responsible for respiration: when inhaling oxygen the muscle contracts to expand the chest cavity allowing air to enter the lungs. As you exhale, the diaphragm relaxes, allowing air to escape.
There is the internal oblique and the external oblique, both in the abdominals. The external ones repress the ribs and move the trunk to one side , while the internal ones produce the flexor movement of the abdomen.
7. Rectus abdominis anterior
This is a very important muscle because it allows the flexion of the spine and contributes to actions of vital importance such as childbirth or defecation . It also holds the abdominal viscera in place.
It is located in the posterior region of the neck and trunk and is important because it facilitates the elevation of the shoulder and the approach of the scapula to the spine . In addition, it collaborates in the rotation of the head.
9. Pectoralis minor
Thin and flat muscle located on both sides of the chest that allows the forward movement of the shoulders and collaborates in the expansion of the rib cage for the exercise of breathing.
10. Pectoralis major
This is located in the anterosuperior region of the thorax and its main function is to rotate the shoulder and flex and abduct it . Due to the composition of its fibers, it can facilitate inspiration when raising the arms.
It gets its name because it is delta-shaped, triangular, and is located in the shoulder. Made up of three parts, it allows extension, abduction and rotation of the shoulder in all directions. Helps the respiratory system.
12. Biceps brachii
It is a muscle of the arm located in its anterior part. Through contraction and coordinating its action with the triceps, it allows movement of the elbow joint.. It also affects shoulder movement.
13. Triceps brachii
It is a muscle located at the same height as the biceps but on the back of the arm. It is the main extensor of the arm in the elbow joint , and also fulfills a function of transmission of blood vessels.
Muscle of the forearm (there is the long radial and the radial) that acts by extending and abducting the hand . It has a slender, elongated shape that extends from the elbow to the base of the third metacarpal.
15. Rectus anterior
Also known as rectus femoris, it is one of the most important of the leg. It is located in the anterior part of the quadriceps and is traversed by the femoral nerve. Is hehip flexor and leg extensor muscle .
16. Quadriceps femoris
Of the muscles of the human body, this is the most voluminous and the one with the most power, since it is responsible for supporting the entire weight of our body. In addition, it activates the movement of our body when walking or running .
17. Vastus lateralis
It is a portion of the quadriceps that extends along the external face of the leg and its main function is to stimulate the movement of the knee in its extension modality. In short, it is the muscle that moves the leg away from the buttock .
Muscle of the anterior region of the thigh that extends with an elongated and very thin shape throughout the leg from the chain to the knee. Sartor means tailor in Latin, and is so called because it allows you to cross your legs like a tailor .
It is called the gastrocnemius muscle and is located in the back of the leg. It is a biarticular muscle because it affects two joints (knee and ankle) and produces plantar flexion of the foot and slightly of the leg.
20. Soleus Behind
the gastrocnemius extends a long thick muscle called the soleus, whose function is the elevation of the curtain, the plantar flexion and the extension of the foot . It is therefore essential for walking and running.
Unknown but important
muscles We have offered you a list of the most important and well-known muscles of the human body, but there are some more that, although they go unnoticed, fulfill important functions. These are the most important unknown muscles.
21. Serratus major
The most curious thing about this muscle is its shape: seen in profile it has the shape of a saw, and that’s where its name comes from. It is located in the upper lateral part of the thorax, and helps to maintain a solid point in the shoulder blade: it is an essential muscle for shoulder mobility . But also, what makes it especially important is that it helps breathing.
Although we have pointed out only the most important ones, the neck area is a mass of medium and small muscles that work like a perfect machine to facilitate the rotation of the neck or the functioning of the organs that help us swallow and breathe.
One of the most important is the splenius, located in the cervical area. It’s one of those muscles you don’t know you have until it hurts , and it allows for rotation, tilt, and extension movements of the neck.
23. Psoas iliaco
With this name, surely you have not heard it in your life. However, this muscle of the body is so important that it supports the upper part with the lower part of the body. It is located in the abdominal cavity and the anterior part of the thigh.
It has the quality of being one of the most powerful in the human body : the main flexor of the thigh and hip is in charge of flexing the body and producing the pulley movement, for example, when we sit up.
It is located at the back of the knee and is one of the great unsung heroes in the movement of walking, because it unlocks the patella, facilitating rotational movement and activation when running or walking.
When the flexion process begins, the popliteus produces a slight internal rotation of the tibia, producing, together with the femur, the function of a key that unlocks the patella.
25. Pelvic floor
The pelvic floor concentrates a large number of small flat muscles that are coordinated when we perform sexual activity. Among other functions, they keep the penis and clitoris erect, and that is why maintaining their toning prevents certain sexual dysfunctions .
In men, for example, some of these muscles regulate ejaculation, and can be toned to delay it and correct premature ejaculation problems.