Biceps

Location: The biceps is a muscle on the front part of the upper arm.

There is a short head and a long head which both work together as a single muscle.

Attachment: The biceps origin is located at the Scapula in the shoulder joint and inserts into the radius and ulna past the elbow joint by the biceps tendon.

Function: When the biceps contracts it pulls the forearm up.

Joint: The insertion is just past the elbow joint.

Joint Type: Hinge Joint

Triceps

Location: The triceps is a muscle on the back part of the upper arm.

There is a lateral, medial and long head that all work together as a connective immovable muscle.

Attachment: The triceps origin is at the humerus and the scapula and inserts into the ulna.

Function: Triceps are primarily responsible for extending the elbow.

Joint: The insertion is at the elbow joint.

Joint Type: Hinge Joint

Deltoids

Location: The deltoid is located on the upper most part of the arm and the top of the shoulder.

It is named after the Greek letter delta that is shaped like an equilateral triangle.

Attachment: The deltoids origin is at the clavicle and scapula and inserts into the humerus

Function: The major function of the scapula is that it lifts the whole arm

The anterior fibers flex and medially rotate the arm The lateral fibers abduct the arm The posterior fibers extends and laterally rotates the arm

Joint Type: Ball and Socket

Trapezius

Location: The trapezius is located on most of the upper back and the posterior of the neck.

There are two trapezius muscles a left and a right that are symmetrical and meet at the vertebral column

Attachment: The trapezius’ origin is at the occipital bone (cranium) and the cervical/thoracic vertebrae and inserts into the clavicle and scapula

Function: The major function of the trapezius is to raise the shoulders (shrugging)

It can also extend the head and neck

Joint: The insertion point is at the clavicle and scapula which form the shoulder joint.

Joint Type: Ball and Socket

Pectoralis Major

Location: The pectoralis major covers much of the front upper chest.

It is a large fan-shaped muscle.

Attachment: The pectoralis major’s origin is at the sternum and the cartilage of the second through the sixth rib. The insertion attaches to the clavicle and the humerus just below the shoulder.

Function: The major function of the pectoralis major is to move the shoulder and arm toward the chest.

Joint: The insertion point is just past the shoulder on the humerus.

Joint Type: Ball and Socket

Latissimus Dorsi

Location: The latissimus dorsi runs obliquely, laterally, and superiorly through the back and armpits.

The name means “broadest muscle of the back.” It is one of the widest muscles in the human body. The shape is triangular.

Attachment: The latissimus dorsi has origins at the thoracic and lumbar vertebrae, sacrum, pelvis and the four most inferior ribs and inserts into the back of the humerus.

Function: The major function of the latissimus dorsi is to pull the arm towards the back.

Joint: The insertion point is on the back of the humerus which lies below the shoulder.

Joint Type: Ball and Socket

Gluteus Maximus

Location: The gluteus maximus covers a large part of the buttocks.

The gluteus maximus is the strongest muscle in the body.

Attachment: The gluteus maximus has origin at the pelvis, sacrum and coccyx and inserts into the femur.

Function: The major function of the gluteus maximus is to straighten the leg and hip.

It is also used to raise the body from a seated position.

Joint: The insertion point is just past the hip on the femur.

Joint Type: Ball and Socket

Abdominals

Location: The abdominals are located between the ribs and the pelvis on the front of the body.

We have four main abdominal muscle groups; the transverse abdominis, the rectus abdominis, the external oblique muscles and the internal oblique muscles.

Attachment: The abdomen originates from the thoracic diaphragm and inserts into the pelvis and between the lumbar vertebrae and sacrum.

Function: The major function of the abdomen is to flex the trunk.

Helps hold organs in place by regulating internal abdominal pressure.

Hamstrings

Location: The hamstrings are located on the back of the upper leg.

The hamstrings are comprised of three separate muscles; the biceps femoris, the semitendinosus, and the semimembranosus.

Attachment: The hamstrings originate just underneath of the gluteus maximus on the pelvic bone and inserts into the tibia.

Function: The major function of the hamstrings is to bend the knee and to extend the hip (moving the leg backwards).

Joint: The insertion point is just past the knee on the tibia.

Joint Type: Hinge Joint

Quadriceps

Location: The quadriceps are located on the front of the upper leg (thigh).

The Latin word quadriceps means “four headed.” The four muscles are the; rectus femoris, vastus lateralis, vastus medialis, vastus intermedius.

Attachment: The vastus lateralis, medialis and intermedius originate from the femur and insert into the patella (knee). The rectus femoris originates from the pelvis and inserts into the patella.

Function: The major function of the quadriceps is to straighten the knee and raise the leg at the hip.

Joint: The insertion point is on the patella.

Joint Type: Hinge Joint

Sartorius

Location: The Sartorius muscle is located on the anterior region of the thigh.

The Sartorius muscle is the longest muscle in the entire body.

Attachment: The Sartorius originates at the pelvis where it then crosses the hip joint and thigh. It then runs down the interior of the knee and descends to insert on the inside of the tibia.

Function: The major function of the Sartorius is rotate the thigh at the hip. It also helps to flex the leg. These functions working together pulls the foot and ankle toward the knee of the opposite leg.

Joint: It works upon both the knee and the hip joints.

Joint Type: Ball and Socket and Hinge Joint

Gastrocnemius

Location: The gastrocnemius is located on the back of the lower leg (calf).

The gastrocnemius has two immovable ends (heads); the medial head and the lateral head.

Attachment: The gastrocnemius originates at the femur (one from the outside/lateral of the femur and the other from the center/medial of the femur. The bottom of the muscle inserts at the Achilles tendon which descends to the heel and inserts into the calcaneus.

Function: The gastrocnemius has the major function of raising you up on your toes.

Joint: The insertion is just past the ankle in the heel.

Joint Type: Hinge Joint

Anterior Tibialis

Location: The anterior tibialis is located on the front of the lower leg (shin).

The gastrocnemius has two immovable ends (heads); the medial head and the lateral head.

Attachment: The anterior tibialis originates at the tibia and runs down the shin and inserts at a tendon that crosses the ankle and attaches to the foot. In the foot the tendon inserts into the metatarsals.

Function: The major function of the anterior tibialis is that it pulls the foot up towards the lower leg.

Joint: Insertion is past the ankle on the foot.

Joint Type: Hinge Joint

Sternocleidomastoid

Location: The sternocleidomastoid is a long muscle on the side of the neck that extends from the thorax (chest) to the skull right behind the ear.

Attachment: The sternocleidomastoid originates at the inside part of the clavicle and inserts at the temporal bones (skull) mastoid process, located near the ear and base of the skull.

Function: The major function of the sternocleidomastoid is to flex the neck and to turn the head side to side.

The sternocleidomastoid also helps in forced inspiration while breathing.