Exam 1

Question 1

Concentric
Eccentric
Isokinetic
(ICE)

Answer 1

C: Shorting of the muscle
E: Lengthens the muscle
I: The speed of the joint

Question 2

Mitochondrion

Answer 2

the powerhouse of the cell and T-Tubule - Passage contracts the outside muscle fiber.

Question 3

Myosin
Actin
S1 Head

Answer 3

M: thick filament
A: thin filament
S1: attachs to actin and active site for ATP. (ATP binding site to power muscle contraction when ATP is hydrolyzed).

Question 4

Troponin

Tropomyosin

Answer 4

Tin: a 3 component protein that is associated with each actin-tropomyosin complex
Tsin: a rod shaped protein acttached to actin in a regular repeating sequence

Question 5

How do you train Fast Twitch (type 2) muscle fibers/motor unit

Answer 5

is primarily trained by sprint distances like anaerobic activity: heavy weight lifting, jump rope, sprint, etc. (Muscle strength)

Question 6

Where does force come from?

Answer 6

Central Nervous System

The chemical signal (action potential) from the brain down the spinal cord that nerves/neurons, activating the contraction of muscle force

Question 7

Fatigue

Answer 7

When the muscle force drops below what you expected to create. It’s when the muscle can’t maintain the force

Question 8

Muscle strength

Answer 8

Is the capacity of a muscle to exert maximal force ONCE against resistance

Question 9

Muscle endurance

Answer 9

Is the capacity of a muscle to exert sub-maximal force repeatedly.

Question 10

Force/Velocity Curve

Answer 10

With an increase in the velocity of contraction, there is a decline in force.

Question 11

Length/Tension

Answer 11

Length of muscle at which it can generate the greatest force retention. Change in muscle length altered actin-myosin interaction, influencing the tension.

Question 12

Muscle Soreness (what is it?) + Eccentric Contraction Process

Answer 12

Lengthening muscle to create an eccentric contraction, which damages the microfibers/sarcomeres in muscle resulting to soreness.

Question 13

What is the Nervous System (CNS) and how does it work?

Answer 13

The system provides rapid communication (wiring) between the brain and the different tissues (muscle) and organs of the body. The brain takes all the information and emits a proper response from the peripheral nerves into the tissues and organs of the body.

Question 14

Functional parts of the CNS (2 parts)

Answer 14

Somatic - all the nerves that leave CNS and go into skeletal muscle

Autonomic - involuntary movements with two different responses of parasympathetic and sympathetic

Question 15

What are the two Autonomic responses? And One example of each

Answer 15

Parasympathetic - rest and digest system (slow responses) ex. Breathing at rest
Sympathetic - the excite response (flight or fight response) ex. Increase HR

Question 16

Nerves

Answer 16

Specialized cells that conduct action potentials along their axon

Question 17

Synapse

Answer 17

Connection between nerve(s) and target tissues membrane, ex. Muscle fiber

Question 18

Receptors

Answer 18

Specific protein located on the membrane of the target tissue that binds to the neurotransmitter released by the nerve to promote an impulse.

Question 19

Motor cortex

Answer 19

a localized region of the outer layers of the brain responsible for the origin of neural processing of complex voluntary movement

Question 20

Cerebellum

Answer 20

located at the base of the posterior region of the brain, the cerebellum refines motor patterns from the motor cortex, and “stores” more-simple or “well trained” motor patterns.

Question 21

Action Potential: rapid depolarization of nerve membrane

Answer 21

membrane is depolarized, and positive ions (Na/Ca) rush into cell, making it transiently positive.

Question 22

The Neuromuscular Junction

Answer 22

As the impulse, as axon goes along the length of that nerve cell. It’s voltage is changed to more positive. It is deeply depolarized and so that goes along the outside of the neuron and gets to the synapse.

Question 23

Henneman’s Size Principle - Process of Motor Unit Recruitment

Answer 23

The pattern of motor unit recruitment that’s fast-twitch or slow-twitch which is altered by the size of cell body that has to be activated or depolarized

Question 24

maximal motor unit recruitment

synchronous recruitment of motor units

Answer 24

Your brain has to work extremely hard to revoke any kind of contraction that’s high force, it has to recruit a lot of motor units and the action potential to surpass the threshold of excitation, because remember fast twitch fibers require a greater a deep depolarization then slow twitch.

Question 25

Hypertrophy

Answer 25

the increased size (cross sectional area) of skeletal muscle fibers.

• Increases in muscle size occur mainly from hypertrophy
• Hypertrophy is greater for resistance than endurance exercise

Question 26

Hyperplasia

Answer 26

the increase in the numbers of muscle fibers within a muscle.
- Hyperplasia probably occurs, but only at a small level

Question 27

Excitation-contraction coupling

Answer 27

is the physiological process of converting an electrical stimulus to a mechanical response. It is the link (transduction) between the action potential generated in the sarcolemma and the start of a muscle contraction.

Question 28

Process of Muscle Contraction

Answer 28

1. muscle contraction represents the ATP demand of exercise
2. depolarization of the sarcolemma of the myofibrils of the motor unit promotes contraction
3. release of Ca from sarcoplasmic reticulum due to action potential, Ca binds to troponin and causes conformational change in actin-tropomyosin complex to open up binding to S1 heads
4. **as long as Ca is available, you have contraction cycling
5. removal of Ca into SR by active transport = muscle relaxation↓ [Ca] = fatigue

Question 29

Sliding Filament Theory

Answer 29

the mechanism that allows muscles to contract

Question 30

How do you train Slow Twitch (type 1) muscle fibers/motor unit

Answer 30

is primarily trained by long distances like aerobic activity: cardio machines, running, swimming, hiking, cycling, etc. (Muscle endurance)