exercise science pse 4u
DESCRIPTION
Muscle Groups of the: 1. Axilla 2. Scapular Region 3. Rotator Cuff 4. Arm 5. Forearm Flexors. Forearm Extensors Gluteal Region Thigh Leg Abdomen Back. Exercise Science PSE 4U. Pectoralis Major. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/1.jpg)
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
![Page 2: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/2.jpg)
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
![Page 3: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/3.jpg)
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
![Page 4: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/4.jpg)
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
![Page 5: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/5.jpg)
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.
![Page 6: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/6.jpg)
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
![Page 7: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/7.jpg)
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
![Page 8: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/8.jpg)
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
![Page 9: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/9.jpg)
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
![Page 10: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/10.jpg)
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
![Page 11: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/11.jpg)
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
![Page 12: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/12.jpg)
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
![Page 13: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/13.jpg)
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
![Page 14: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/14.jpg)
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
![Page 15: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/15.jpg)
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
![Page 16: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/16.jpg)
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)
![Page 17: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/17.jpg)
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.
![Page 18: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/18.jpg)
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
![Page 19: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/19.jpg)
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
![Page 20: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/20.jpg)
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
![Page 21: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/21.jpg)
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
![Page 22: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/22.jpg)
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
![Page 23: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/23.jpg)
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
![Page 24: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/24.jpg)
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
![Page 25: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/25.jpg)
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
![Page 26: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/26.jpg)
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
![Page 27: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/27.jpg)
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
![Page 28: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/28.jpg)
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
![Page 29: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/29.jpg)
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
![Page 30: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/30.jpg)
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
![Page 31: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/31.jpg)
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
![Page 32: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/32.jpg)
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
![Page 33: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/33.jpg)
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)
![Page 34: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/34.jpg)
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)
![Page 35: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/35.jpg)
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)
![Page 36: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/36.jpg)
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
![Page 37: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/37.jpg)
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
![Page 38: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/38.jpg)
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)
![Page 39: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/39.jpg)
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
![Page 40: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/40.jpg)
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
![Page 41: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/41.jpg)
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
![Page 42: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/42.jpg)
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
![Page 43: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/43.jpg)
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
![Page 44: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/44.jpg)
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
![Page 45: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/45.jpg)
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
![Page 46: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/46.jpg)
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
![Page 47: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/47.jpg)
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
![Page 48: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/48.jpg)
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
![Page 49: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/49.jpg)
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
![Page 50: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/50.jpg)
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
![Page 51: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/51.jpg)
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
![Page 52: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/52.jpg)
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
![Page 53: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/53.jpg)
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
![Page 54: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/54.jpg)
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
![Page 55: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/55.jpg)
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)
![Page 56: Exercise Science PSE 4U](https://reader037.vdocument.in/reader037/viewer/2022102619/56814532550346895db1faec/html5/thumbnails/56.jpg)
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