1. MUSCULAR SYSTEM  How many muscles?  How many type of muscles?  How Do Muscles Work?  What is the function of the Muscular System?  Location and action of muscles? 

2. MUSCULAR SYSTEM  There is a total of 434 muscles in the body  Makes up 40-55% of the total bodyweight  Distributed in pairs on the R @ L sides of the body  75 muscle pairs are responsible for body movements and posture  Remaining muscles are used for activities like eye control and swallowing

3. MUSCULAR SYSTEM  Types of Muscles  Smooth- Muscles that act on the lining of the body’s passageways and hollow internal organs. * Found in the digestive tract, urinary bladder, the lining of the blood vessels, and passageways to the lungs. Smooth muscles are involuntary muscles.  Cardiac-type of striated muscle that forms the wall of the heart. * Involuntary muscles responsible for the contraction of your heart. The heart contracts rhythmically about 100,00 times each day to pump blood throughout your body * Involuntary muscles responsible for the contraction of your heart. The heart contracts rhythmically about 100,00 times each day to pump blood throughout your body

4. MUSCULAR SYSTEM  Skeletal-muscles that attached to bone that cause body movements * Voluntary muscles that work together to perform opposite actions to produce a movement. * Voluntary muscles that work together to perform opposite actions to produce a movement.  Flexor-muscle that close a joint  Extensor-muscle that opens a joint

5. MUSCULAR SYSTEM  Attached to Bones  When muscles shorten pulls the two attached sites together  Can be viewed as an actual chain between bones  No ability to push bones only pull them together  Bone-Tendon-Muscle-Tendon-Bone

6. MUSCULAR SYSTEM Muscular Attachment  Location  More proximal attachments  More stable end of attachment  Insertion  More Distal  Typically attaches to the bone that moves  Frequently has a long tendon as its attachment

7. MUSCULAR SYSTEM  Muscles pull equally on both attachment sites  Which bones remain stationary depends on purpose of movement and stability provided by other muscles

8. MUSCLES OF THE ARM Biceps Brachii  Location: anterior side of humerus  2 parts  Long Head  Short Head  Action: Flexes the forearm at the elbow when supinated.  Supinated- rotation of the forearm and hand so the palm faces forward or upward and the radius lies parallel to the ulna

9. MUSCLES OF THE ARM Triceps Brachii  Location: Posterior side of Humerus  3 parts  Long Head  Lateral Head  Medial Head  Action: extends the forearm at the elbow

10. BACK MUSCULATURE Trapezius  Location: Base of Neck to middle of the back/shoulder blades  Action: elevates scapula, retracts scapula Latissimus Dorsi  Location: Upper back below and to the sides of the shoulder blades (scapula)  Action: adduction and extension of humerus  Adduction: the lateral movement of a limb towards the midline of the body

11. BACK MUSCULATURE Rhomboid Major  Location: upper back between shoulder blades (scapula)  Action: Adduction of the scapula Erector Spinae Muscles Location: on either side of the spine Action: extends torso

12. CHEST MUSCULATURE Pectoralis Major  Location: covers most of the rib cage  Action: adducts humerus, flexion of the arm from extension

13. Shoulder Musculature Deltoids  Location: cover shoulders  Action: abducts arm, Flexion (anterior portion), extension (posterior portion)  Abduction: The movement of a limb away from the midline of the body  Anterior- toward the front  Posterior- toward the rear

14. Shoulder Musculature Rotator Cuff Supraspinatus, Infraspinatus,Teres Minor Supraspinatus, Infraspinatus,Teres Minor  Location: surround head of humerus  Action: externally rotate upper arm Subscapularis  Location: surround head of the humerus  Action: internally rotate upper arm

15. GLUTEAL MUSCULATURE Tensor Fascia Lata  Location: Lateral portion of the femur  Action: hip flexion, abduction Gluteus Maximus  Location: outer rim of ilium  Insertion: IT Band (primary insertion), gluteal tuberosity femur  Action: powerful extensor of hip

16. THIGH MUSCULATURE Semitendinous, Semimembranosus, Bicep Femoris  Location: Posterior side of leg  Action: Flexor at the knee, extends hip Adductor Magnus Location: medial side of thigh Action: adducts and extends the thigh

17. THIGH MUSCULATURE Rectus Femoris  Location: Front of the thigh  Action: extends knee, flexes hip Vastus Lateralis, intermedius, medialis  Location: Front of the thigh  Action: extends knee

18. Lower Leg Musculature Gastrocnemius Location: behind the shin (Tibia, Fibula) Action: plantar flex the ankle

19. ABDOMINAL MUSCLES Oblique (love Handles)  Location: Lateral side of abdomen  Action: lateral flexion or rotation Tranverse Abdominus  Location: deep in front of abdomen  Action: Tenses abdominal wall and compresses abdominal contents Rectus Abdominus  Location: on surface of abdomen (six pack)  Action: flexes thoracic and lumbar spine against resistance, tenses abdominal wall

20. Muscle Properties  Extensibility-Can be lengthened or stretched  Elasticity- will return to its original shape when lengthened or stretched  When stretched it absorbs energy and enhances the development of force  Contractility/Irritability- unique property possessed by muscle tissue only

21. Muscle Properties  Has the ability to:  Be irritated in response to nerve stimulus,  Contracts or develops tension in response to nerve stimulus  Conduct the electrical signals from the stimulus effect  When motor neuron fire it stimulates muscle fibers

22. Force Relationships  Gravity  Body works in the following ways:  Opposing gravity (upward)  With the direction of gravity (downward)  Perpendicular to gravity (sideways)  The same muscles will be used when movement occurs in all three situations

23. Force Relationships  However they will be used differently:  When opposing muscle shortens when going with lengthens or relaxes  When going across gravity does not effect the movement in same way  Other external forces will though  Tug of war vs extending arm

24. Muscle during Tension development  Muscle Actions  Auxotonic- muscle action in which both tension and speed change during the movement  Concentric-Action in which the proximal and distal muscle attachment move towards each other (shortening)  Eccentric- Action in which the proximal and distal muscle attachment move away from each other (lengthening)

25. Understanding Muscular Problems  Bruises- discolored skin that appears after an injury, usually caused by a blow or direct contact to the skin. Injury causes a blood vessel beneath the skin to rupture.  Strains/Sprains- results when muscles are stretched or partially torn from overextertion.  Tendinitis- inflammation of the tendon, oeruse or natural ageing. Treatment includes ultrasound or anti-inflammatory medication.

26. Understanding Muscular Problems  Hernia-when an organ or tissue protrudes through an area of weak muscle. Commonly occur in the abdomen region from lifting a heavy object. Surgery is usually recommended.  Muscular Dystrophy- an inherited disorder in which skeletal muscle fibers ate progressively destroyed. No cure but with early detection muscle weakness can be delayed through exercise program.