1. Movement Analysis

2. Neuromuscular Function:
I. The Motor Unit:

4. II. The Structure of Muscle Tissue:

10. III. The Role of Neurotransmitters in stimulating skeletal muscle contraction:
A. Acetylcholine (Ach): increases the post-synaptic membrane’s permeability to sodium and potassium ions spreading the impulse over the entire muscle fiber.

13. B. Cholinesterase: enzyme that breaks down Ach repolarizing the muscle fiber to await another nerve impulse.

14. IV. Skeletal Muscle Contraction:

16. A. The sliding filament theory:
Steps of a muscle contraction:
*Ca++ are released by the sarcoplasmic reticulum.
*Ca++ binds to troponin preventing the blocking action of tropomyosin.

17. Sliding filament cont.
*myosin heads can now attach to active sites on the actin filament.
*using ATP, the myosin heads pulls on the actin filament.
*myosin head releases the actin when a new ATP is formed.

20. V. Types of Muscle Fibers:
Slow Twitch: (type 1)
*smaller in diameter
*reddish color
*use aerobic resp. for ATP supply
*contain more mitochondria
*fire slowly, but take long to fatigue.

21. B. Fast Twitch: used for short explosive movements, stop and go sports.
Type IIA:
*large diameter
*white in color
*less mitochondria
*uses both anaerobic and aerobic energy transfer
Type IIB:
*same physical characteristics as Type IIA, but strictly uses the glycolytic anaerobic system.

22. Joint and Movement Type
Types of Joint Movement:
Abduction: movement away from the body’s center.
Adduction: movement towards the body’s center.

23. 3. Circumduction: making circular movements.
4. Dorsiflexion: movement of the ankle elevating the sole. (digging in the heel)
5. Plantar flexion: extending the ankle and elevating the heel. (standing on tiptoes)

24. 6. Elevation: occurs when a structure moves in a superior (towards head) manner. Ex. Closing your mouth/elevating the shoulders.
7. Depression: movement is inferior (towards feet). Ex. opening your mouth/lowering the shoulders

25. 8. Extension: movement that increases the angle between articulating elements opening the joint.
9. Flexion: decreases the angle between articulating elements and closes the joint.

26. 10. Pronation: rotating the palm down.
11. Supination: rotating the palm up.
12. Rotation: turning the body around a longitudinal axis.

27. 13. Inversion: when the ankle rolls outward.
14. Eversion: ankle roles inward.

29. B. Types of Muscle Contraction:
Isotonic: describes concentric and eccentric muscle actions.
Concentric: muscle is shortened during contraction.
Eccentric: muscle is contracting while lengthening.

30. 2. Isometric: muscle generates force without changing length. Ex
2. Isometric: muscle generates force without changing length. Ex. Hand grip and plank position.
3. Isokinetic: the speed of movement is fixed and the resistance varies with the force exerted.
*requires special equipment!

31. C. Reciprocal Inhibition: describes muscles on one side of a joint relaxing while the other side is contracting. (antagonistic pairs)
Agonist: muscle that causes the movement.
Antagonist: muscle that works opposite the agonist to return the joint to its initial position.

32. D. Delayed Onset Muscle Soreness: (DOMS)
The pain and stiffness felt in muscles several hours to days after unaccustomed or strenuous exercise.
*brought on by eccentric contractions of the muscle causing pressure at the nerve endings.

33. Biomechanics: the science concerned with the internal and external forces acting on the human body and the effects they produce on the body.
Force: a pushing or pulling action that causes a change of state (rest/motion) of a body.
*proportional to mass x acceleration
*measured in Newtons (N)

34. b. Speed: describes the rate at which a body moves from one location to another.
*obtained by dividing the distance traveled by the time taken.
*speed is described in terms of magnitude (amount) which makes it a scalar quantity.

35. c. Distance vs. Displacement
Distance: the length of a path a body follows.
Displacement: the length of a straight line joining the start and finish points.

36. d. Velocity: the rate at which a body moves from one location to another with both magnitude and direction making it a vector quantity.
*obtained by dividing the displacement by the time taken.

37. e. Acceleration: is defined as the rate at which velocity changes over time and the ability to change ones speed from either a static position or a moving state.
* Final velocity – initial velocity/time

38. f. Momentum: is a vector describing a “quantity of motion” and is the product of mass and velocity.
*an athlete can increase their momentum by either increasing their mass or velocity.

39. g. Impulse: the effect of force over time
g. Impulse: the effect of force over time. Calculated as the product of force and time.

40. h. Center of mass: the point at which the body is balanced in all directions.
*a change in body position can change the position of the center of mass within or outside the body.

41. The Fosbury Flop!
*notice how the center of gravity is located outside the jumper’s body.

42. Examples of the center of gravity outside the body.

44. Levers: rigid structures hinged at one point (fulcrum) to which forces are applied to two other points (effort and load)
1. First Class Lever:
The fulcrum lies between the effort and load.
Ex. Triceps extension and picking the chin up from the chest.

45. 2. Second Class Lever: the fulcrum lies at one end with the effort at the other and the load in the middle. Ex. Standing heel raise

46. 3. Third Class Levers: the effort lies between the load and the fulcrum. Ex. Biceps curl swinging a bat.

47. Types of Levers

48. Newton’s Laws of Motion in Sport
1. First Law: a body in motion/rest will remain in motion/rest in a straight line unless acted upon by another force. Also known as inertia.

49. 2. Second Law: the rate of change of momentum of a body is proportional to the force causing it and the change takes place in the direction in which the force acts. (F= M A)

50. 3. Third Law: For every action there is an equal and opposite reaction
3. Third Law: For every action there is an equal and opposite reaction. (every force involves the interaction of two objects)