Exercise Science PSE 4U

Exercise SciencePSE 4U

Muscle Groups of the:

1. Axilla

2. Scapular Region

3. Rotator Cuff

4. Arm

5. Forearm Flexors

6. Forearm Extensors

7. Gluteal Region

8. Thigh

9. Leg

10. Abdomen

11. Back

Group 1Muscles of the Axilla

Pectoralis Major Description: A large fan shaped muscle – covers upper portion of chest, forms anterior of axillary fold

Origin: Clavicle, sternum, and ribs 1-7

Insertion: Crest of greater tubercle of humerus

Action: Flexes, adducts and medially rotates arm

Group 1Muscles of the Axilla

Pectoralis Minor Description: A flat thin muscle directly beneath and obscured by the pectoralis major. Forms anterior wall of Axilla

Origin: Anterior surface of ribs 3-5

Insertion: Coracoid process of the scapula

Action: Depresses the scapula and elevates ribs 3-5

Group 1Muscles of the Axilla

Serratus Anterior Description: Forms medial wall of axilla. Serrated or sawtooth appearance. Lies deep to scapula and beneath & inferior to pectoral muscles on lateral rib C1

Origin: Outer surface of ribs1-9Insertion: Entire length of

vertebral border of the scapula

Action: Stabilizes, abducts and rotate the scapula upward

Group 1Muscles of the Axilla

Subscapularis Description: Forms part of posterior wall of axilla; a “rotator cuff” muscle

Origin: Subscapular fossaInsertion: Lesser tubercle

of the humerusAction: Extends and

medially rotates the arm, stabilizes shoulder joint.

Group 1Muscles of the Axilla

Teres Major Description: A thick rounded muscle found inferior to the teres minor. Helps form posterior wall of axilla

Origin: Axillary border of scapula

Insertion: Lesser tubercle of the humerus

Action: Adducts, extends and medially rotates the arm

Group 1Muscles of the Axilla

Latissimus Dorsi Description: A broad flat, triangular muscle of the lower back (lumbar region). Forms part of posterior wall of axilla

Origin: Spinous processes of T7-T12 and L1-L5, the sacrum, iliac crest, and ribs 10-12

Insertion: Intertubercular groove of the humerus

Action: Extends, adducts and medially rotates the arm; pulls shoulder inferiorly

Group 2Muscles of the Scapular Region

Trapezius Description: A flat triangular muscle, upper fibers run downward to scapula, middle fibers run horizontally to scapula, lower fibers run superiorly to scapula

Origin: Occipital bone, the ligamentum nuchae, and the spinous processes of C7-T12

Insertion: Lateral 1/3 of clavicle and the spine of the scapula

Action: Abducts and extends head, rotates and adducts scapula

Group 2Muscles of the Scapular Region

Levator Scapulae Description: Thick strap like muscle located at back & side of the neck, deep to trapezius;

Origin: Transverse processes of C1-C4

Insertion: Superior angle of scapula

Action: Elevates scapula, and rotates and abducts neck

Group 2Muscles of the Scapular Region

Rhomboid Major Description: A rectangular shaped muscle lying deep to trapezius and inferior to levator scapulae. Inferior to rhomboideus minor.

Origin: Spinous processes of T1-T4

Insertion: Inferior, vertebral border of the scapula

Action: Adducts, stabilizes and rotates the scapula

Group 2Muscles of the Scapular Region

Rhomboid Minor Description: A rectangular shaped muscle lying deep to trapezius and inferior to levator scapulae

Origin: Spinous processes of C6-C7

Insertion: Superior, vertebral border of the scapula

Action: Adducts, stabilizes and rotates the scapula

Group 2Muscles of the Scapular Region

Deltoid Description: Responsible for roundness of shoulder

Origin: Clavicle, acromion process, and spine of the scapula.

Insertion: Deltoid tuberosity of the humerus

Action: Abducts, flexes, extends medially, and laterally rotates the arm

Group 3Muscles of the Rotator Cuff

Consists of 4 musclesa) Supraspinatusb) Infraspinatusc) Teres Minord) Subscapularis (mnemonic S.I.T.S.

- they sit on the shoulder)

*If any of the rotator cuff muscles is damaged due to strain or badmechanics, the consequences are serious for arm/shoulder actions

Group 3Muscles of the Rotator Cuff

Supraspinatus Description: Named for its location on posterior aspect of scapula

Origin: Supraspinous fossa of the scapula

Insertion: Greater tubercle of the humerus by a common tendon with Infraspinatus and Teres Minor

Action: Abducts arm and stabilizes the shoulder

Group 3Muscles of the Rotator Cuff

Infraspinatus Description: Partially covered by deltoid & trapezius

Origin: Infraspinous fossa of the scapula

Insertion: Greater tubercle of the humerus by common tendon with Supraspinatus & Teres Minor.

Action: Extends, laterally rotates arm and stabilizes the shoulder

Group 3Muscles of the Rotator Cuff

Teres Minor Description: Small, elongated muscle that lies inferior to infraspinatus

Origin: Axillary border of the scapula.

Insertion: Greater tubercle of the humerus by common tendon with supraspinatus & infraspinatus

Action: Same action as infraspinatus muscle

(Extends, laterally rotates arm and stabilizes the shoulder)

Group 3Muscles of the Rotator Cuff Subscapularis Description: A large

triangular muscle, and the only muscle in the group located on the anterior surface of the scapula

Origin: Subscapular fossa of the scapula

Insertion: Lesser tubercle of the humerus

Action: Medially rotates humerus and stabilizes the shoulder.

Group 4Muscles of the Arm

Triceps Brachii Description: Large fleshy muscle and the only muscle of posterior compartment of the arm

Origin: Long head= Infraglenoid tuberosity of the scapula

Lateral and medial heads= posterior surface of humerus

Insertion: Olecranon process of the ulna

Action: Extends the forearm and arm, and adducts the arm

Group 4Muscles of the Arm

Coracobrachialis Description: A small cylindrical muscle.

Origin: Coracoid process of the scapula

Insertion: Medial shaft

of the humerus

Action: Flexion & adduction of the humerus

Group 4Muscles of the Arm

Brachialis Description: Strong muscle that is immediately deep to the biceps brachii

Origin: Anterior, distal humerus

Insertion: Coronoid Process of the ulna

Action: Flexion of the forearm

Group 4Muscles of the Arm

Anconeus Description: A short triangular muscle closely associated with distal end of triceps

Origin: Lateral epicondyle of the humerus

Insertion: Olecranon process of the ulna

Action: Extends the forearm

Group 5Forearm Flexors

Pronator Teres Description: A two headed muscle

Origin: Medial epicondyle of the humerus and the coronoid process of the ulna

Insertion: Middle shaft of the radius

Action: Pronates and weakly flexes the forearm

Group 5Forearm Flexors

Flexor Carpi Radialis Description: Runs diagonally across the forearm; midway, its fleshy belly is replaced by a flat tendon that becomes cordlike at wrist

Origin: Medial epicondyle of the humerus

Insertion: 2nd and third meta carpals

Action: Flexes & abducts the hand; aids in flexion and pronation of forearm. Powerful flexor of wrist

Group 5Forearm Flexors

Flexor Carpi Ulnaris Description: Most medial muscle of this group; two headed

Origin: Medial epicondyle of humerus; olecranon process; posterior surface of ulna

Insertion: Pisiform, hamate & 5th metacarpal

Action: Flexes & adducts the hand; powerful flexor of wrist

Group 7Muscles of the Gluteal Region

Gluteus Maximus Description: Largest and strongest, most superficial of gluteal muscles; forms bulk of buttock mass; fibers are thick & coarse.

Origin: Lateral surface of ilium, sacrum and coccyx

Insertion: Lateral condyle of tibia by lateral fascia and gluteal tuberosity of the femur

Action: Extends, abducts, and laterally rotates the thigh

Group 7Muscles of the Gluteal Region

Gluteus Medius Description: Thick muscle largely covered by gluteus maximus and sits on top of gluteus minimus

Origin: Outer ilium, between the posterior & the anterior gluteal lines

Insertion: Greater trochanter of the femur

Action: Abducts & medially (internal) rotates the thigh

Group 7Muscles of the Gluteal Region

Gluteus Minimus Description: Smallest and deepest of the gluteus muscles

Origin: Outer (external) ilium, between the anterior and the inferior gluteal lines

Insertion: Greater trochanter of the femur

Action: Abducts and medially (internally) rotates the thigh; same action as the gluteus medius

Group 7Muscles of the Gluteal Region

Sartorius Description: A superficial anterior muscle of the thigh. It derives its name from the latin word sartor meaning “to mend”.

Origin: Anterior superior iliac spine

Insertion: Medial surface of the tibia

Action: The sartorius acts across two joints: Flexes and laterally rotates the hip and flexes the knee

Group 7Muscles of the Gluteal Region

Quadratus Femoris: Description: Short thick muscle; most inferior of lateral rotator muscles, extends laterally from pelvis

Origin: Ischial TuberosityInsertion: Shaft of the femur

just below the greater trochanter

Action: Laterally rotates the thigh and stabilizes hip joint

Group 8Muscles of the Thigh Anterior Compartment

SartoriusDescription: A superficial

anterior muscle of the thigh. It derives its name from the latin word sartor meaning “to mend”.

Origin: Anterior superior iliac spine

Insertion: Medial surface of the tibia

Action: The sartorius acts across two joints: Flexes and laterally rotates the hip and flexes the knee

Group 8Muscles of the Thigh Anterior Compartment

IIiopsoasDescription: A composite of

two closely related muscles: iIiacus and psoas major

Origin: Psoas major – the transverse processes and bodies of T12 and L1-L5

IIiacus – iliac fossa and sacrum

Insertion: Lesser trochanter of femur

Action: Flex the thigh; flex the trunk on the femur

Group 8Muscles of the Thigh

Rectus Femoris Description: Superficial, straight muscle of the anterior thigh; longest head and only muscle of the group to cross the hip joint

Origin: Anterior inferior iliac spine

Insertion: Tibial tuberosity, via the patella and the patellar ligament

Action: Extends the leg (knee) and flexes the thigh

Group 8Muscles of the Thigh

Vastus Lateralis Description: Forms lateral aspect of thigh

Origin: Greater trochanter and the lateral lip of the linea aspera of the femur

Insertion: Tibial tuberosity, via the patella and the patellar ligament

Action: Extend the leg (knee)

Group 8Muscles of the Thigh

Vastus Medialis Description: Forms inferomedial aspect of thigh

Origin: Medial lip of the linea aspera of the femur

Insertion: Tibial tuberosity, via the patella and the patellar ligament

Action: Extends the leg (knee)

Group 8Muscles of the Thigh

Vastus Intermedius Description: Lies between vastus lateralis and vastus medialis on anterior thigh

Origin: Anterior, lateral shaft of the femur

Insertion: Tibial tuberosity, via the patella and the patellar ligament

Action: Extend the leg (knee)

Group 8Muscles of the Thigh

Pectineus Description: Short flat muscle; overlies adductor brevis on proximal thigh

Origin: Superior ramus of the pubis

Insertion: Posterior femur just below the lesser trochanter

Action: Adducts and laterally rotates the thigh

Group 8Muscles of the Thigh

Adductor Longus Description: Most anterior of adductor muscles

Origin: Crest and the symphysis of the pubis

Insertion: Middle 1/3 of the linea aspera of the femur

Action: Adducts and laterally rotates the thigh

Group 8Muscles of the Thigh

Adductor Brevis Description: Largely concealed by adductor longus and pectineus

Origin: Inferior ramus of the pubis

Insertion: Upper part of the linea aspera of the femur

Action: Adducts and laterally rotates the thigh (femur)

Group 8Muscles of the Thigh

Adductor Magnus Description: A triangular muscle with a broad insertion; a composite muscle that is part adductor and part hamstring in action

Origin: Inferior ramus of the pubis and the ischium

Insertion: Most of the length of the linea aspera, and the adductor tubercle of the femur

Action: Adducts, flexes, extends and laterally rotates the thigh

Group 8Muscles of the Thigh

Gracilis Description: Long, thin, superficial muscle of the medial thigh

Origin: Symphysis pubis and the pubic arch

Insertion: Proximal portion medial tibia just below the condyle

Action: Adducts the thigh and flexes the leg

Group 8Muscles of the Thigh

Biceps FemorisL.H. S.H.

Description: Most lateral muscle of the group; arises from two heads

Origin: Long head-ischial tuberosity

Short head-distal linea aspera

Insertion: Head of fibula, and the lateral condyle of the tibia

Action: Flexes and laterally rotates the leg (knee), long head extends thigh

Group 8Muscles of the Thigh

Semitendinosus Description: Lies medial to biceps femoris, quite fleshy; its slendedr tendon begins about 2/3 way down the thigh

Origin: Ischial TuberosityInsertion: Medial, proximal end

of the tibiaAction: Extends thigh, flexes

and medially rotates leg

Group 8Muscles of the Thigh

Semimembranosus Description: Deep to semitendinosus

Origin: Ischial tuberosity

Insertion: Medial, proximal end of the tibia

Action: Extends thigh, flexes and medially rotates leg

Group 9Muscles of the Leg

Anterior CompartmentTibialis Anterior

Description: Superficial muscle of anterior leg; laterally parallels sharp anterior margin of tibia

Origin: Lateral tibiaInsertion: Medial cuneiform &

first metatarsalAction: Dorsiflexes & inverts

the foot

Group 9Muscles of the Leg

Anterior CompartmentExtensor Digitorum Longus

Description: On anterolateral surface of leg; lateral to tibialis anterior

Origin: Lateral condyle of the tibia, proximal shaft of the fibula

Insertion: Dorsal surface of the phalanges of digits 2-5

Action: Dorsiflexes & everts the foot; extends digits 2-5

Group 9Muscles of the Leg

Anterior CompartmentExtensor Hallucis Longus Description: Deep to

extensor digitorum longus & tibialis anterior; narrow origin

Origin: Medial shaft of fibula, and interosseous membrane

Insertion: Distal phalanx of the hallux (1st digit)

Action: Dorsiflexes & inverts foot; extends the hallux

Group 9 Muscles of the Leg

Superior CompartmentGastrocnemius: Description: Superficial

muscle of pair; two prominent bellies that form proximal curve of calf

Origin: Medial & lateral condyles of the femur

Insertion: CalcaneusAction: Flexes the leg and

plantar flexes the foot

Group 9Muscles of the Leg

Posterior CompartmentSoleus

Description: Deep to gastronemius on posterior surface of calf

Origin: Posterior fibula and tibia

Insertion: CalcaneusAction: Plantar flexes the foot

and important during walking, running & dancing

Group 9: Muscles of the LegPosterior Compartment – Deep

MusclesPopliteus:

Description: Thin, triangular muscle at posterior knee; passes downward & medially to tibial surface

Origin: Lateral condyle of the femur

Insertion: Proximal portion of the tibia

Action: Flexes the leg & rotates it medially to unlock knee from full extension when flexion begins

Group 10Muscles of the Abdominal WallExternal Abdominal

Oblique:Description: Largest & most

external of the abdominal oblique muscles; fibers run downward & medially; aponeurosis turns under inferiorly forming inguinal ligament

Origin: External surface of ribs 5-12 (fleshy strips)

Insertion: Linea alba, iliac crest and inguinal ligament

Action: Compresses the abdomino pelvis cavity and laterally rotates; aids in lateral flexion

Group 10Muscles of the Abdominal wall

Internal Abdominal Oblique: Description: Fibers fan upward & forward and run at right angles to those of external oblique (which it underlies)

Origin: Inguinal ligament and iliac crest

Insertion: Linea alba and inferior 4 ribs

Action: same as external abdominal oblique

Group 10Muscles of the Abdominal Wall

Transversus Abdominis: Description: Deepest (innermost) muscle of abdominal wall; fibers run horizontally

Origin: Inguinal ligament, iliac crest, lumbodorsal fascia and ribs 7-12

Insertion: Linea alba, and pubic crest

Action: Compresses the abdomen and laterally rotates trunk

Group 10 Muscles of the Abdominal Wall

Rectus Abdominis: Description: Medial superficial muscle pair; is located on each side of a tendinous line (linea alba) extending from xiphoid process of sternum to the pubis; segmented by three reinforcing tendinous intersections horizontally which give the abs the classic washboard appearance

Origin: Pubic Crest and symphysis pubis

Insertion: Xiphoid process & cartlidges of ribs 5-7

Action: Compresses the abdomen and flexes lumbar vertebrae

Group 11Muscles of the Back

Erector Spinae Muscle Spinalis:

Description: Most medial muscle column of erector spinae

Origin: Spinous process of the upper lumbar, lower thoracic, and 7th cervical vertebrae

Insertion: Spinous processes of the upper thoracic & the cervical vertebrae

Action: Extends the vertebral column

Group 11Muscles of the Back

Erector Spinae Muscle Longissimus: Description: Intermediate tripartite

muscle group of erector spinae; mainly pass between transverse processes of the vertebrae

Origin: Transverse processes of the lumbar, thoracic & lower cervical vertebrae

Insertion: Transverse processes of the vertebrae above the vertebra of origin, and the mastoid process of temporal bone (capitis)

Action: Extend the vertebral column & head; acting on oneside bend it laterally; capitis extends the head & turns face towards same side (bend laterally)

Group 11Muscles of the Back

Erector Spinae Muscle Ilio Costalis:

Description: Most lateral muscle group of erector spinae muscles; extend from pelvis to neck

Origin: Crest of the sacrum; spinous processes of the lumbar & lower thoracic vertebrae; iliac crests; angles of the ribs

Insertion: Angles of the ribs; transverse processes of the cervical vertebrae

Action: Extend the vertebral column & acting on one side, bend it laterally maintain erect posture