Major Components of the Muscular System

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While muscles are often associated with brute strength, they play a crucial role in vital bodily functions. Muscles are essentially the propellers of all your body’s movements. From the twitch of an eye to a simple heartbeat, some of the most basic movements of the body would not be possible without muscles. Because of its sophisticated muscular system, the human body is capable of performing a plethora of complex movements. The efficacy of the muscular system is due to the harmonious function of its fundamental components.

Types of Muscles

You cannot see and do not have direct control over some types of muscles. Muscles are grouped into three categories: cardiac, smooth, and skeletal. The cardiac muscles are found in your heart. They are designed to be resistant to fatigue and work with consistency. Smooth muscle is found in your hollow organs such as your blood vessels and gastrointestinal tract. They are very flexible and are responsible for the contraction of the hollow organs. Because cardiac and smooth muscles are involuntary, you cannot control them directly. Your body performs these functions automatically. Skeletal muscle is the type of muscle that is attached to your bones. Unlike cardiac and smooth muscles, skeletal muscle is voluntary. It is the type of muscle that you can actually improve with proper nutrition and exercise. When people talk about muscles, they are usually referring to skeletal muscle.

Structure and Arrangement

As its name implies, skeletal muscle works in harmony with the bones to propel your body’s movements. Muscles work with bones through tendons. Tendons are bands of fibrous tissue that connects muscles to bones. They act as an intermediate between your muscles and bones. The Achilles tendon is a good example of this because it connects your gastrocnemius and soleus muscles to the heel. Ligaments connect different bones. They are primarily located at the joints. With the aid of tendons and ligaments, skeletal muscle works with bones to effectuate your body’s movements.

Movements and Mechanics:

Your muscles work together to trigger the fundamental movements of your body. Whenever you perform a basic movement, several muscle groups act together to support and provide stability. Muscles generally play one of the following roles during a basic movement: agonist, antagonist, synergist, and fixator. Agonist muscles are the “prime movers” or the cause of a specific movement. The antagonists are the muscles that have the ability to act in opposition to that movement. These are known as antagonistic pairs. The biceps brachii and triceps brachii are antagonistic pairs. Synergists work together to deliver a specific movement. For example, the brachioradialis works with the biceps brachii to flex the arm. Fixators are the wide range of muscles that help provide stability during a movement.

Locations and Basic Functions

Because muscles are found everywhere in the body, they trigger a variety of movements. The muscles of your face facilitate the display of various facial emotions such as anger, sadness, and joy. They also assist in food ingestion. Your back is primarily composed of the latissimus dorsi, trapezius, and rhomboid muscles. Some of their main roles are adduction and abduction—which are the movements of a limb toward and away from the body. The anterior part of the upper body consists of the pectoralis major, serratus anterior, rectus abdominis, and external oblique muscle. The anterior side of the thigh is made up of the quadriceps, and the posterior side is made up of the hamstrings. The quadriceps extend the legs, while the hamstrings flex them. The anterior part of your lower leg is composed of the tibialis anterior, and the posterior compartment is made up of the gastrocnemius and soleus muscles. The tibialis anterior raises your forefoot, while the gastrocnemius and soleus muscles raise your heel. Your arms are composed of the biceps brachii, triceps brachii, and other muscles found in the forearms. Their main roles are to flex and extend your arm.