1. MUSCULAR SYSTEM Nearly half our weight comes from muscle tissue.
There are 650 different muscles in the human body.

2. THREE MAIN FUNCTIONS Responsible for all body movement.
Responsible for body form and shape (posture)
Responsible for body heat and maintaining body temperature.

3. MUSCLE TYPES
SKELETAL
TYPES OF MUSCLES
SMOOTH
CARDIAC

4. Skeletal Muscle Attached to bone VOLUNTARY
Contract quickly, fatigue easily, can’t maintain contraction for long period of time

5. Cardiac Muscle Found only in the heart Involuntary
Creates it’s own stimulus
Cells are fused – when one contracts, they all contract

6. Cardiac Muscle Review of Cardiac Muscle
What is the pacemaker of the heart called?
SA node
What are they vessels that provide O2 to the heart called?
Coronary arteries
When the heart is deprived of O2, what happens? MI

7. Cardiac Muscle
What is the chest pain felt when the heart is deprived of O2?
Angina
What do we call beats that are originated outside of the SA node?
Ectopic beats/arrhythmias
What is the deadliest arrhythmia?
Ventricular fibrillation

8. Smooth Muscle Visceral (organ) muscle
Found in walls of digestive system, uterus and blood vessels
INVOLUNTARY= Autonomic Nervous
System
Act slowly, do not tire easily, can remain contracted for long time

9. SPHINCTER
special circular muscles in openings between the esophagus and stomach
What are they called????
Cardiac sphincter pyloric sphincter
Also found at anus, urethra and mouth.

10. CHARACTERISTICS OF MUSCLES
CONTRACTIBILITY – the ability of a muscle to reduce the distance between the parts of its contents or the space it surrounds.
Unique to muscle tissue
EXCITEABILITY (IRRITABILITY) – the ability to respond to certain stimuli by producing impulses.
Only muscle and nervous tissue have this ability

11. CHARACTERISTICS OF MUSCLES
EXTENSIBILITY – the ability to be stretched.
ELASTICITY – ability of muscle to return to its original length when relaxing.

12. Contraction of Muscle Tissue
Muscle contraction occurs as a result of 2 events:
1. “myoneural stimulation” stimulation of the muscle nerve
2. contraction of the muscle
MOTOR UNIT – a motor neuron plus all the muscle fibers it stimulates.

14. MUSCLES *Zygomaticus smile
*Sternocleidomastoid flexes and rotates the head
Allows us to turn our heads from side to side, nod
*Pectoralis Major flexes upper arm
Abduct/adduct arm across the chest

15. also a site for an “IM” injection
MUSCLES
Deltoid abducts and extends upper arm
also a site for an “IM” injection
Intramuscular
Biceps flexes lower arm

16. MUSCLES Rectus Abdominis allows you to -bend forward at the waist
“rectus” means straight
-compresses abdominal area
“6 pack”
Sartorius flexes and rotates the thigh
makes an “S” across the femur

17. MUSCLES Tibialis anterior flexes the foot
-allows us to walk on our heels
“Quads” group rectus femoris
-extends the lower leg

18. MUSCLES External abdominal obliques
-allow us to bend side to side at the waist
-use the obliques, diaphragm and the intercostal muscles to breathe

19. MUSCLES Trapezius major muscles of upper back
-pulls shoulders back, extends the head
Triceps extends the lower arm
Latissimus dorsi major muscles of lower back
-most of all back movements

20. MUSCLES Gluteus medius triangle shaped muscle on hip area IM site
Gluteus Maximus “butt cheeks”
-extends and rotates the femur
outward

21. MUSCLES “Hamstring” group Semitendinosus
-flexes, extends and abducts the thigh
Gastrocnemius “calf muscle”
-flexes lower leg
-points toes, allows us to walk on our tiptoes
Achille’s Tendon anchors the gastrocnemius to the calcaneus
-if it is cut or damaged, we can’t walk

22. MOVEMENT Muscles move bones by pulling on them. Muscles never push!!!!
Muscles must be attached to bones for leverage.
Tendons attach muscles to bones
Ligaments attach bones to bones

23. Muscle Attachments Both ends of a muscle are attached to bones
Insertion: moves the bone.
Origin:  does not move or is less movable.
Movement occurs at the joint between the insertion and origin.
STUCK FINGER ACTIVITY********

24. MOVEMENT
Groups of muscles usually contract to produce a single movement.
Muscles are arranged in pairs in the body.
i.e. Biceps and triceps

25. MOVEMENT produce a movement opposite to that of the prime movers.
PRIME MOVER - muscle whose contraction is mainly responsible for producing a given movement.
ANTAGONIST - muscle whose actions
produce a movement opposite to that of the prime movers.
i.e. biceps- are the prime movers to flex the lower arm
triceps would be the antagonist to extend the lower arm

26. Sources of Energy and Heat
When muscles work they produce heat
Muscles major energy source is ATP
As a muscle works ATP is released in the form of heat

27. Sources of Energy and Heat
During exercise the muscles use up their supply of O2
Lack of O2 causes incomplete oxidation of glucose
The byproduct of this incomplete oxidation is a buildup of
LACTIC ACID

28. Sources of Energy and Heat
The accumulation of the lactic acid in the muscle causes
MUSCLE FATIGUE
or cramping
When exercise is finished, you have to breathe in enough O2 for the muscles to complete the oxidation process
Then respirations will return to normal

29. Muscle Contractions
MUSCLE TONE - When muscles are slightly contracted and ready to pull.
ISOTONIC CONTRACTION - When muscles contract and shorten. (Walk, talk, etc.)
ISOMETRIC CONTRACTION - When the tension in a muscle increases but the muscle does not shorten. (exercises such as tensing the abdominal muscles.)

30. Muscle Size Muscle atrophy muscles become weak, shrink cause deformity
Muscle hypertrophy muscle fiber increases in size

31. Muscle Size

32. Muscle Size

33. Disorders and Related Terminology
STRAIN
tear in the muscle resulting from excessive use.
Bleeding inside the muscle can result in pain and swelling.
Ice packs will help stop bleeding and reduce swelling.

34. Disorders and Related Terminology
MUSCLE SPASM (cramp)
sustained contraction of the muscle, usually because of overuse.
MYALGIA
Muscle pain

35. Disorders and Related Terminology
HERNIA
Organs can protrude through a weak muscle.
A hiatal hernia occurs when the stomach pushes through the diaphragm.

36. HERNIA
Abdominal Hernia
Inguinal Hernia

37. Disorders and Related Terminology
FLAT FEET (TALIPES)
Weakening of leg muscles that support the arch
Downward pressure on the foot eventually flattens out the arches.
Condition can be helped by exercise, massage and corrective shoes.

38. FLAT FEET (TALIPES)

39. Disorders and Related Terminology
TETANUS (lockjaw)
Infectious disease
Continuous spasms of voluntary muscles.
Enters the body through puncture wound.
Prevented by vaccine.

40. Disorders and Related Terminology
TORTICOLLIS
inflammation of the trapezius and/or sternocleidomastoid muscle.
“crick” in the neck
Treated with physical therapy and anti-inflammatory medications.

41. Disorders and Related Terminology
MUSCULAR DYSTROPHY
Group of diseases in which muscle cells deteriorate.
Most common is Duchenne Muscular Dystrophy,
Characterized by progressive weakness and eventual death
Diaphragm is effected

42. RECREATIONAL INJURIES
TENNIS ELBOW
Tendon that connects arm muscle to elbow becomes inflamed due to overuse.
Treated with RICE.

43. TENNIS ELBOW

44. RECREATIONAL INJURIES
SHIN SPLINTS
Injury to the muscle /tendon in the front of the shin. (tibialis anterior muscle)
Caused by jogging.
Choose correct running shoes with proper arch support.

45. SHIN SPLINTS

46. RECREATIONAL INJURIES
ROTATOR CUFF DISEASE
Inflammation of tendons around shoulder joint.
Due to repetitive overhead swinging. (baseball pitcher)
Treated with rest and physical therapy. (RICE)

47. ROTATOR CUFF DISEASE

48. CONTRACTURE Tightening or shortening of a muscle.
Commonly seen in patients who cannot exercise a muscle due to paralysis.
TENDONITIS
Inflammation of a tendon

49. CUMULATIVE TRAUMA DISORDERS
Also called repetitive motion disorders
Caused by repeated muscle use, such as using a keyboard.
Prevented by varying tasks and ergonomically designed devices.

50. CUMULATIVE TRAUMA DISORDERS
ERGONOMICS
Study of the application of biology and engineering to the relationship between workers and their environment.
INTRAMUSCULAR INJECTION
medication injected into skeletal muscle
usually the deltoid in the arm, or gluteus medius in the buttocks.