Not only the muscles but also the role of the skeletal system is very important in human movement. Muscles and bones work together to aid in movement. The role of muscles in locomotion is mentioned below.
1. Flexor Muscles: Muscles that contract or bend a limb are called flexor muscles. The process of bending or contracting a part of a flexor muscle is called flexion. For example, the biceps muscle bends the elbows or fingers
2. Extensor Muscles: Muscles that stretch or spread a limb are called extensor muscles. The process of extending or spreading a part of an extensor muscle is called extension. For example, the triceps muscle extends the forearm.
3. Adductor muscle: The muscle that pulls any part of the body closer is called adductor muscle. The process of pulling an adductor muscle to a limb is called adduction. For example, the latissimus muscle pulls an organ closer.
4. Abductor muscle: The muscle that moves a part of the body away is called abductor muscle. Abduction is the movement of a part of the abductor muscle away. For example, the deltoid muscle moves an organ away.
5. Depressor muscle: The muscle that lowers any part of the body is called depressor muscle. The process by which a depressor muscle moves down a limb is called depression. For example, the mandibula muscle lowers the jaw.
6. Levator muscle: The muscle that raises any part of the body is called levator muscle. The process of raising a limb of the levator muscle is called levitation. For example, the masseter muscle raises the jaw. Gastrocnemius muscle of knee, soleus muscle of foot etc.
7. Rotator Muscle: The muscle that rotates any part of the body around or right-left is called rotator muscle. Rotation is the process of turning a part of the rotator cuff around or left and right. For example, the pronator muscle causes lateral rotation and the supinator muscle causes lateral rotation. The piriformis muscle helps rotate the femur.
8. Protractor Muscle: The muscle that extends a part of the body forward is called a protractor muscle.
9. Retractor Muscles: Muscles that extend a body part backwards are called retractor muscles.