1. Chapter 10 The Muscular System

2. Muscles and Body Movements
Muscles are attached
to at least two points
Origin – attachment to
an immoveable bone
Insertion – attachment
to a movable bone

3. Effects of Exercise on Muscle
Results of increased muscle use
Increase in muscle size
Increase in muscle strength
Increase in muscle efficiency
Muscle becomes more fatigue resistant

4. Types of Ordinary Body Movements
Flexion
Extension
Rotation
Abduction
Circumduction

5. Body Movements

6. Special Movements Dorsifelxion Plantar flexion Inversion Eversion
Supination
Pronation
Opposition

7. Types of Muscles
Prime mover – muscle with the major responsibility for a certain movement
Antagonist – muscle that opposes or reverses a prime mover
Synergist – muscle that aids a prime mover in a movement and helps prevent rotation
Fixator – stabilizes the origin of a prime mover

8. Naming of Skeletal Muscles
Direction of muscle fibers
Example: rectus (straight)
Relative size of the muscle
Example: maximus (largest)

9. Naming of Skeletal Muscles
Location of the muscle
Example: many muscles are named for bones (e.g., temporalis)
Number of origins
Example: triceps (three heads)

10. Naming of Skeletal Muscles
Location of the muscles origin and insertion
Example: sterno (on the sternum)
Shape of the muscle
Example: trapezoid (triangular)
Action of the muscle
Example: flexor and extensor (flexes or extends a bone)

11. Head and Neck Muscles Orbicularis oculi (25) Zygomaticus (25)
Orbicularis oris (25)
Mentalis (25)
Masseter (25)
Temporalis (25)
Sternocleidomastoid (26)

12. Green= sternocleidomastoid
Important for muscle in rotation, flexion, and extension of the head.

13. Deep Trunk and Arm Muscles
Plate A: sternocleidomastoid (26), trapezius (31), deltoid (33), latissimus dorsi (33)
Plate B; Erector spinae (27) a) iliocstalis (27), b) longissimus (27), c) spinalis (27)
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

15. Trunk Muscles
Plate a: deltoid(33), pectoralis major (33), biceps (34), brachialis (34), brachioradialis (34)
Plate b: rectus abdominis (28), transversus abd. (28), internal oblique (28), external obl. (28)
Slide 6.39
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

17. Iliopsoas:
Psoas major
Iliacus
Play a role in hip joint flexion and balancing the torso during sitting.

18. Deep Trunk and Arm Muscles
Plate A: sternocleidomastoid (26), trapezius (31), deltoid (33), latissimus dorsi (33)
Plate B; Erector spinae (27) a) iliocstalis (27), b) longissimus (27), c) spinalis (27)
Slide 6.40
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

24. Muscles of the Pelvis, Hip, and Thigh
Iliopsoas (41)
a) iliacus
b) psoas major
Sartorius (41)
Quadriceps femoris (41)
a) rectus femoris
b) vastus lateralis
c) vastus medialis
d) vastus intermedius
located under rect. Fem.
Adductor Group (40)
a) adductor magnus
b) adductor longus
c) adductor brevis

25. Muscles of the Lower Leg
Plate B:
Gastrocnemius (43)
Soleus (43)
Slide 6.42

28. Superficial Muscles: Anterior
Orbicularis oris vastus medialis
Pectoralis major tibialis anterior
External oblique tensor fascia lata
Sternocleidomastoid rectus abdominus
Biceps brachii
Deltoid transversus abdominus
Vastus lateralis
Frontalis
Rectus femoris
Sartorius
Gracilis
Adductor group
Peroneus longus
Temporalis
Orbicularis oculi
Zygomaticus
Masseter
Slide 6.43

29. Superficial Muscles: Posterior
Gluteus maximus
Gluteus medius
Gluteus minimus (under maximus)
Adductor muscles
Gastrocnemius
Soleus
Latissimus dorsi
Deltoid
Semitendinosus
semimembranosus
Trapezius
Biceps femoris
Triceps brachii
External oblique
Slide 6.44