If all the muscles in the body could pull in one direction, in one giant movement, the force would = 25 tonnes. 1 tonne

1. Quick Facts! • If all the muscles in the body could pull in one direction, in one giant movement, the force would = 25 tonnes. • 1 tonne = 907.18 kg = 2240 lbs • The average person’s muscles do daily work that amounts to loading 24,000 lbs on to a 4 foot high shelf. • To cause movement, both ends of each muscle must be attached to bone: What are the 2 types of attachments?

2. Origin and Insertion • Origin • Insertion • Function • Action / Movement • What the muscle does when activated

3. Principles of Muscle Action • A tendon crossing front will produce extension (knee) • A tendon crossing back will produce flexion (knee) • A tendon crossing lateral side of the ankle will produces eversion (while one passing medially (medial malleoulus) produces inversiion • Whichever end offers less resistance will usually move

4. Antagonistic Pairs • Skeletal muscles are arranged in opposing pairs • Since a muscle cannot expand, another muscle is required to move the bone in the opposite direction to stretch the first muscle • Agonist Muscle • Antagonist Muscle • See Table 3.3 in your text • Fixator

5. Fixator – • Eg. Teres major connects the scapula to the humerus • In order for the Teres major to do adduction, the Rhomboids must fixate the scapula • Another common example, the abdominals fixate the pevis to allow contraction of hip flexors (walking / running) Synergist – • Eg – grip of fingers – grip strength is increased when wrist is fixed in extension • The more you flex your wrist, the weaker your grip becomes!

6. These are the Muscles that you are required to Learn: Upper Body Muscles – 42 (colour grouped) Lower Body Muscles – 23 (colour grouped)

7. Work Time ! Using the textbook pages 46 – 63, fill in your workbook or a spreadsheet to identify the origin, insertion, & movement / function of the given muscles. You should also colour in the appropriate diagram in your workbooks

8. Face Muscles

9. Various functions of the facial muscles: • Keeping food in the mouth • Allowing you to chew • Allowing you to form words • Tongue • Function:

10. Facial Muscles

11. Neck Muscles

12. Neck Muscles • There are muscles posterior, lateral and anterior to the neck or cervical region • These muscles:

13. Sternocleidomastoids • The most important anterior pair of muscles Sternocleidomastoid

14. Os Coxae Sacrum Erector Spinae muscles • When someone faints, these muscles no longer function and the body falls face forward to the ground • The erector spinae muscles also overlap each other in upper, middle and lower segments allowing one segment to fixate allowing segmental control of vertebral column (activities like dance and gymnastics) Erector spinae

15. Muscles of the Abdomen

16. Muscles of Thoracic Cage • The Diaphragm • Intercostal Muscles

17. Normal anatomy of the diaphragm. Drawing shows the central tendon (arrow) and the crura attachments to vertebral columns (arrowheads). IVC= aperture for the inferior vena cava.

18. Thoracic Cage

19. External Obliques Transversus Abdominis Internal Obliques Obliques • External oblique • Internal oblique • Transversus abdominus • Functions: • Rotation of the abdomen • Allow the development of a pregnant uterus

20. Rectus Abdominis Rectus Abdominus • Strengthening of the abdominal muscles is a very important part of back therapy, because the abdominals act to support the back.

21. Muscles of the Shoulder

22. Muscles that affect the Shoulder joint fall into 4 categories: • They have origins on the Scapula http://www.youtube.com/watch?v=twWWa7F5qxU&feature=related

23. 1) – Muscles that act on the Humerus 2 Largest Superficial muscles • Anterior • Posterior

24. 2) Muscles that Anchor the Scapula to Axial Skeleton These 6 muscles link the scapula to the axial skeleton: • The actions of these muscles is determined by the direction of travel of the fibres – the scapula will then move accordingly

25. 3) Rotator Cuff Muscles Muscles of the Rotator Cuff • They essentially wrap around the shoulder joint to hold it in place • “S.I.T.S.” – acronym that explains how they sit on the shoulder girdle– as well as to name the muscles

26. 4) Scapular Muscles that Move the Humerus • All these muscles have origins on the scapula and act to move the humerus

27. Quick Review...

28. Review ! 5 1 6 2 7 3 8 4 .

29. Review ! 9 10 13 14 11 15

30. Create a chart / table that groups muscles according to their MOVEMENT! It will help you with the actions of the muscles! Suggestion!

31. Muscles of the Arm: a) b)

32. Muscles of the Arm • The muscles in this section control movement of the forearm and can be divided into 2 groups: • They are involved in three joints:

33. Anterior Compartment: Posterior Compartment

34. b) Supination and Pronation of the Forearm- - What do notice about the insertion of all pronators and supinators? Why is that?

35. Muscles of the Forearm, Wrist and Hand

36. Forearm muscles act on the elbow, wrist and digits (fingers) • Generally speaking…. • Helpful when applying the names of forearm muscles to what they bones they move…

37. Applying your knowledge of anatomical terms (and the pictures) – what do these muscles do?

38. Muscles of the Hip

39. Posterior Muscles • Gluteals • Include 3 muscles: • Gluteus maximus • Gluteus medius • Gluteus minimus Gluteus Medius Gluteus Minimus Gluteus Maximus

40. Muscles of the Hip1)Anterior Hip Compartment • Iliopsoas

41.  2) Medial Compartment of Thigh Adductors: • Medial muscle • Superior, but below Longus • Most inferior Pectineus Adductor Brevis Adductor Longus Adductor Magnus

42. Thigh Muscles

43. Quadriceps • Quadriceps • no origin on femur • Only 2 joint quadricep • Name describes their location Rectus Femoris Vastus Lateralis Sartorius Vastus Intermedius Vastus Medialis

44. Posterior Compartment of Thigh • Hamstrings • Has an origin on femur Long Head of Biceps Femoris Semitendinosis Short Head of Biceps Femoris Semimembranosis

45. Lower Leg Muscles

46. Lower Leg Muscles • They can be organized into 3 compartments: • Note the “mirror-like” similarity between muscles of anterior and posterior compartments Common Actions

47. Lower Leg Compartments NOTE: Here is an example of how muscles cross the axis of the joint will influence their actions. For example: Tib. Ant crosses in front of ankle – dorsiflex. Peroneus Longus Tibialis Anterior Gastrocnemius Peroneus Brevis Soleus Calcaneal Tendon

48. Lateral Compartment - FYI • Proximally attach to the lateral surface of the tibia • Distally attach to the foot • Movement: Peroneus Longus Peroneus Brevis

49. That’s All the Muscles you are required to know!

50. Review Questions - 1