1. Muscular System
Muscles

2. Review Define the following words: Inferior Superior Proximal Distal
Deep
Superficial
Medial
Lateral

3. Golden Rule of Skeletal Muscle Activity
With few exception, all muscles cross at least one joint
Typically, the bulk of muscles lies proximal to the joint crossed
All muscles have at least two attachments to muscle: the origin and the insertion
Muscles can only pull, they can never push
During contraction, the muscle insertion moves towards the origin

4. Insertion: attachment to the moveable bone
Origin: the part of the muscle that is attached to the immovable or less moveable bone
Insertion: attachment to the moveable bone
The insertion point will always move toward the origin when muscles contract
Many muscles have interchangeable origins and insertions

5. Body Movements They come in mostly opposite pairs
Be ready to move with me!

6. Body movements Flexion: decreases the angle of the joint
Extension: increases the angle of the two bones or parts of the body

7. Body movements
Rotation: movement of the bone around its longitudinal axis
Prime example: shaking your head “no”

8. Body movements Abduction: moving the limb away from the midline
Think about the word: if someone abducts you, they are taking you away from home
Adduction: movement of a limb towards the body midline

9. Body movements
Circumduction: a combo of flexion, extension, abduction, and adduction
The whole limb outlines a cone

10. Body movements
Dorsiflexion or plantar flexion: up and down movements of the foot
Lifting the foot towards your shin = dorsiflexion
Pointing your toe = plantar flexion

11. Body movements Inversion: turning the sole of your foot medially
Eversion: turning the sole of your foot laterally

12. Body movements Supination: palm faces anteriorly
Like you are holding a cup of soup
Pronation: palm faces posteriorly
Like you are dribbling a ball like a “pro” W/NBA player

13. Body movements
Opposition: thumb touches the tips of your other fingers
Remember: the opposable thumb is one of the things that separates us from monkeys

14. Muscles to know We will focus on agonist pairs
This means that they oppose each other
Ie one will flex and the other will extend
Let’s start from the head down!

15. Head/neck-Anterior Sternocleidomastoid
Flex your neck when both sides contract
Rotate your neck when one side contracts

16. Head/neck-posterior Trapezius Extend the head Adduct the shoulders
Work to have your shoulder blades touch

17. Chest/shoulder
Pectoralis major
Adducts and flexes the arm

18. Chest/shoulder
Deltoid
Arm abduction

19. Trunk-anterior
Rectus abdominis
Flex the vertebral column

20. Trunk-posterior
Erector spinae
Back extensors
Very deep to the spine

21. Upper limb-anterior
Biceps brachii
Flexion of the forearm

22. Upper limb-posterior
Triceps brachii
Extension of the forearm

23. hips
Gluteus maximus
Hip extensor

24. Thigh-anterior Quadriceps group Rectus femoris Vastus medialis
Vastus intermedius
Vastus lateralis
Flex the hips
Extend knee

25. Thigh-posterior Hamstrings Biceps femoris Semimembranosus
Semitendinosus
Flex the knee

26. Leg-anterior
Tibialis anterior
Dorsiflex and invert the foot

27. Leg-posterior
Gastrocnemius and soleus
Plantar flexion