1. Anatomy-Muscular System
Skeletal Muscle Characteristics &
Function

2. Introduction How many skeletal muscles can you identify?
What is a concentric contraction?
Eccentric contraction?
Isometric contraction?

3. Objectives Students will be able to:
Identify skeletal muscles, their attachments & action

4. Terminology
Dorsiflexion
Upward bending of the foot
Pulling toes up

5. Terminology Plantar Flexion Downward bending of the foot Pointing toes
Dancers primarily plantarflex

6. Terminology Protraction Retraction Anteriorly rounded shoulders
Squeeze scapula's together

7. Terminology Adduction Abduction Add back to the body
Away from the body/midline

8. Terminology Flexion Extension
Decreasing the angle of the joint; to bend
Extension
Increasing the angle of the joint; to straighten

9. Terminology
Inversion
Toes moving inward
Eversion
Toes moving outward

10. Face Masseter Origin Zygomatic arch Insertion Mandible Action
Closes the jaw
Raises the mandible

11. Masseter
The Chewing Muscle!
How would we CONTRACT this muscle?

12. Neck Muscle Sternocleidomastoid Origin Sternum (near manubrium)
Sterno – Sternum
Cleido – Clavicle
Mastoid – Mastoid Process
Origin
Sternum (near manubrium)
Clavicle (medial end)
Insertion
Mastoid Process

13. Sternocleidomastoid Action Bilaterally, Flex Cervical
Unilaterally, rotation to opposite side

14. Abdominals Rectus Abdominis Origin Pubis Insertion Xiphoid process
Costal cartilage (5-7)

15. Rectus Abdominus Action Compresses/stabilizes abdominal cavity
Flexion of trunk

16. Upper Extremity Muscles
Trapezius
Origin
Occipital
Spinous process C7-T12
Insertion
Lateral clavicle
Scapular spine

17. Trapezius What exercises could someone do to work their traps? Action
Elevation
Depression
Retraction
Stabilizes scapula
What exercises could someone do to work their traps?
Shrugs
Upright Row
Scap Retraction with bands

18. Upper Extremity Latissimus Dorsi Origin Spinous process T6-S5
Iliac crest
Insertion
Medial humerus

19. Latissimus Dorsi
Action
shoulder
Adduction of humerus

20. Upper Extremity Pectoralis Major Origin Medial clavicle Sternum
Costal cartilage (1-6)
Insertion
Proximal Humerus

21. Pectoralis Major
Action
Flexion
Adduction of humerus

22. Upper Extremity Deltoid - Anterior Origin Lateral clavicle Insertion
Deltoid tuberosity of humerus

23. Anterior Deltoid
Action
Flexion
Horizontal adduction of humerus

24. Upper Extremity Deltoid - Middle Origin Acromion process Insertion
Deltoid tuberosity of humerus

25. Middle Deltoid
Action
Abduction of humerus to 90 degrees

26. Upper Extremity Deltoid - Posterior Origin Scapular spine Insertion
Deltoid tuberosity of humerus

27. Posterior Deltoid
Action
Extension
Horizontal abduction of humerus

28. Flash Card Time! On one side: Name
Make Flash Cards for the following:
Masseter
Sternocleidomastoid
Rectus Abdominus
Trapezius
Latissimus Dorsi
Pectoralis Major
Deltoid
Anterior
Middle
Posterior
On one side: Name
On opposite side: Origin, Insertion & Action

29. Muscles of the Shoulder
The muscles of the shoulder run from the scapula to the humerus/forearm
What anatomical movements can the shoulder perform?
What muscle groups do you know?

30. Rotator Cuff Muscles
They originate on the scapula & insert on the humeral head
They hold the head of the humerus IN the Glenoid Fossa of the Scapula.
Keep shoulder in socket.
4 Muscles make up the Rotator Cuff:
Supraspinatus
Infraspinatus
Teres Minor
Subscapularis

31. Supraspinatus Origin: Insertion Action Supraspinous Fossa of Scapula
Greater Tubercle of Humerus
Action
Abduction of humerus
Stabilize head of humerus

32. Supraspinatus in Action!
Laying a ball up in basketball
Jumping Jack
Abduction of shoulder

33. Infraspinatus What view is this picture? Origin
Infraspinous fossa of scapula
Insertion
Greater tubercle of humerus
Action
Lateral rotation of humerus
Or External Rotation
Stabilize head of humerus
What view is this picture?

34. Infraspinatus in Action!

35. Teres Minor Origin Lateral boarder of scapula Insertion
Greater tubercle of humerus
Action
Lateral rotation of humerus
External Rotation
Stabilize head of humerus

36. Teres Minor in Action!
Much like the Infraspinatus…working on lateral rotation exercises enhances this muscle
What other sports would need to strengthen their teres minor?

37. Subscapularis Origin Subscapular fossa of scapula Insertion
Lesser tubercle of humerus
Action
Medial rotation of humerus
Internal rotation
Stabilize head of humerus

38. Actions of Rotator Cuff
Abduction
External Rotation
External rotation
Internal Rotation
Supraspinatus
Infraspinatus
Teres minor
Subscapularis

39. Biceps Brachii Origin Short Head-coracoid process
Long Head-supraglenoid tubercle of scapula
Insertion
Radial tuberosity
Action
Flexion of elbow

40. Biceps in Action Discuss: Eccentrically Contract
Concentrically Contract
Isometrically Contract

41. Triceps Brachii Origin Long Head Lateral Head Medial Head Insertion
Infraglenoid tubercle of scapula
Lateral Head
Posterior humerus
Medial Head
Insertion
Olecranon process of ulna
Action
Extension of elbow

42. Triceps In Action!

43. Skeletal Muscle On one side: Name
Make Flash Cards for the following:
Supraspinatus
Infraspinatus
Teres Minor
Subscapularis
Biceps Brachii
Triceps Brachii
On one side: Name
On opposite side: Origin, Insertion & Action

44. Muscles of the Thigh
The muscles of the thigh run from the hip to the knee
What movements can the hip and knee joint perform?
What muscles/muscle group do you know?

45. Gluteus Maximus Origin Posterior sacrum & ilium Insertion
Gluteal tuberosity of femur
Action
Extension of femur/hip
External Rotation of hip

46. Glute Strength Squats are known to help build glute strength…
What other exercises would concentrically contract this muscle?

47. Hamstrings Biceps Femoris Origin Long head-ischial tuberosity
Short head-posterior femur
Insertion
Head of fibula
Action
Extension of hip
Flexion of the knee

48. Hamstrings Semitendinosus Origin Ischial tuberosity Insertion
Anterior tibia
Action
Extension of hip
Flexion of the knee

49. Hamstrings Semimembranosus Origin Ischial tuberosity Insertion
Posterior medial tibia
Action
Extension of hip
Flexion of the knee

50. Hamstrings O: Ischial tuberosity I: Fibula & Tibia
A: Flex knee Extend hip
Semitendinosus
Biceps Femoris
Semimembranosus

51. Hamstrings
Biceps Femoris
Semitendinosus
Semimembranosus

52. Quadriceps Rectus Femoris Origin Anterior inferior iliac spine (AIIS)
Insertion
Tibial tuberosity
Action
Extension of the knee
Hip flexion

53. Quadriceps Vastus Lateralis Origin Lateral Femur Insertion
Tibial tuberosity
Action
Extension of the knee

54. Quadriceps Vastus Medialis Origin Medial Femur Insertion
Tibial tuberosity
Action
Extension of the knee

55. Quadriceps Vastus Intermedius Origin Anterior femur Insertion
Tibial tuberosity
Action
Extension of the knee

56. Lower Extremity Rectus Femoris Vastus Lateralis Vastus Medialis
Vastus Intermedius

57. Skeletal Muscle Quads On one side: Name
Make Flash Cards for the following:
Gluteus Maximus
Hamstrings
Biceps Femoris
Semitendinosus
Semimembranosus
Quads
Rectus Femoris
Vastus Lateralis
Vastus Medialis
Vastus Intermedialis
On one side: Name
On opposite side: Origin, Insertion & Action

58. Final Chapter! Today will be the muscles of the low leg
This last group of muscles is the end of this muscle segment.
So far we have identified:
Face and Neck
Shoulders and Back
Abs and Glutes
Hamstrings and Quads
Today will be the muscles of the low leg
What is one muscle group that you already know?
Calf Muscles
Why do you think they call them the calves?
I have no idea!!

59. Lower Extremity Tibialis Anterior Origin Lateral condyle of tibia
Insertion
Plantar surface of 1st metatarsal
Action
Dorsiflexion
Recall….what does this mean?
Inversion of ankle

60. Dorsiflexion & Inversion
Pointing toes out:
EVERSION
Pulling toes up:
DORSIFLEXION
Pointing toes down:
Plantarflexion
Pointing toes in:
Inversion

61. Lower Extremity Peroneus Longus Origin Proximal fibula Insertion
Plantar surface of 1st metatarsal
Action
Eversion of ankle

62. Lower Extremity Peroneus Brevis Origin Distal middle ½ fibula
Insertion
Base of 5th metatarsal
Action
Eversion of ankle

63. Eversion Exercises A commonly used rehab tool are resistance bands
Eversion exercises strengthen the Peroneus Longus and Peroneus Brevis

64. Lower Extremity Soleus Origin Upper tibia Posterior fibula Insertion
Calcaneus (Heel Bone)
Action
Plantarflexion of ankle

65. Lower Extremity Gastrocnemius Origin
Medial head-medial epicondyle of femur
Lateral head-lateral epicondyle of femur
Insertion
Calcaneus (Heel Bone)
Action
Plantarflexion of ankle
This muscle is SUPERFICIAL to the Soleus

66. Gastrocnemius vs. Soleus
To isolate the SOLEUS
To isolate the GASTROC

67. Skeletal Muscle On one side: Name
Make Flash Cards for the following:
Tibialis Anterior
Peroneus Longus
Peroneus Brevis
Soleus
Gastrocnemius
On one side: Name
On opposite side: Origin, Insertion & Action

68. Skeletal Muscle List of muscles learned
Name
Origin, Insertion & Action
Masseter
Sternocleidomastoid
Rectus Abdominus
Trapezius
Latissimus Dorsi
Pectoralis Major
Deltoid
Anterior
Middle
Posterior
Supraspinatus
Infraspinatus
Teres Minor
Subscapularis
Biceps Brachii
Triceps Brachii
Tibialis Anterior
Peroneus Longus
Peroneus Brevis
Soleus
Gastrocnemius
Gluteus Maximus
Hamstrings
Biceps Femoris
Semitendinosus
Semimembranosus
Quads
Rectus Femoris
Vastus Lateralis
Vastus Medialis
Vastus Intermedialis

69. Skeletal Muscle