❌The Neuromuscular System

Question 1

What does the autonomic nervous system do?

Answer 1

Regulates the function of our internal organs such as the heart and also controls controls some of our skeletal muscles within the body.

It works involuntary.

Question 2

What controls the movement of muscles?

Answer 2

The brain via nerves

Question 3

What is the neuromuscular system?

Answer 3

Where the nervous system and the muscles work together to allow movement.

Question 4

What is the peripheral nervous system.

Answer 4

The sympathetic and parasympathetic nervous system.

Their role is to transmit information from the brain to parts of the body that need to adjust what they are doing to prepare for exercise.

Question 5

What is the sympathetic nervous system?

Answer 5

Prepares the body for exercise and is often referred to as the ‘fight or flight response’.

Question 6

What is the parasympathetic nervous system?

Answer 6

Has the opposite effect of the sympathetic system and relaxes the body and slows down many high energy functions.
It is often explained by the phrase ‘rest and relax’.

Question 7

What does aerobic mean?

Answer 7

Literally means ‘with oxygen’ so it refers to exercise that is low to medium intensity where the oxygen demand of the muscles can be met.

Question 8

What does anaerobic mean?

Answer 8

Means ‘without oxygen’ and refers to exercise at a high intensity such as sprinting, where the demand for oxygen by the muscles is so high that it cannot be met.

Question 9

What are the types of muscle fibre?

Answer 9

Slow oxidative (type I) (also known as slow twitch)
Fast oxidative glycolytic (type IIa)
Fast glycolytic (type IIb)

Question 10

What performer will have more slow twitch fibres?

Answer 10

Endurance athlete

Question 11

What performer will have more fast twitch fibres?

Answer 11

Sprinter

Question 12

What are slow twitch fibres?

Answer 12

These fibres have slower contraction speed than fast twitch fibres and are better adapted to lower intensity exercise such as long-distance running.
They produce most of their energy aerobically (using oxygen) and therefore have specific characteristics that allow them to use oxygen more effectively.

Question 13

What are fast twitch fibres?

Answer 13

These fibres have a much faster contraction speed and can generate a greater force of contraction.
However, they do fatigue very quickly and are used for short, intense bursts of effort.
They produce most their energy anaerobically

Question 14

What is a motor unit?

Answer 14

A motor neurone and it’s muscle fibres.

Question 15

What are motor neurones?

Answer 15

Nerve cells which transmit the brains instructions as electrical impulses to the muscles.

Question 16

What is a neuromuscular junction?

Answer 16

Where the motor neurone and the muscle fibre meet.

Question 17

How many muscle fibre types are found in a motor unit?

Answer 17

Only one type can be found in one particular motor unit.

Question 18

What is the all or none law?

Answer 18

Where a sequence of impulses has to be of sufficient intensity to stimulate all of the muscle fibres in a motor unit in order for them to contract. If not, none of them contract.

Question 19

What is the threshold?

Answer 19

Minimum amount of stimulation.

Question 20

How does a contraction occur?

Answer 20

Muscles fibres work with the nervous system so that a contraction can occur.
The motor neurone transmits the nerve impulses to the muscle fibre.
Each motor neurone has branches that end in the neuromuscular junction on the muscle fibre.

Question 21

What type of muscle fibres do motor units contain?

Answer 21

Either slow twitch or fast twitch

Question 22

When does the brain recruit slow twitch motor units?

Answer 22

For low intensity activity such as jogging or long-distance swimming.

Question 23

When does the brain recruit fast twitch motor units?

Answer 23

If a greater force of contraction is needed.

For activities such as sprinting or power lifting.

Question 24

How do you increase the strength of contraction?

Answer 24

Wave summation

Spatial summation

Question 25

What is wave summation?

Answer 25

Where there is a repeated nerve impulse with no time to relax so a smooth, sustained contraction occurs, rather than twitches.

Question 26

What is a tetanic contraction?

Answer 26

A sustained muscle contraction caused by a series of fast repeating stimuli.

Question 27

What is spatial summation?

Answer 27

When the strength of a contraction changes by altering the number and size of the muscles motor units.

Question 28

What does PNF stand for?

Answer 28

Proprioceptive neuromuscular facilitation.

Question 29

What is PNF?

Answer 29

Its an advanced stretching technique.

Flexibility training

Question 30

What’s the most practical PNF technique?

Answer 30

CRAC technique.

Contract-relax-antagonist-contract.

Question 31

What are muscle spindles?

Answer 31

They detect how far and how fast a muscle is being stretched and produce the stretch reflex.

Question 32

What are golgi tendon organs?

Answer 32

These are activated when there is tension in a muscle.

Question 33

What are muscle spindles and golgi tendon organs?

Answer 33

Proprioceptors

Question 34

What triggers the stretch reflex?

Answer 34

Muscle spindles provide information (excitory signals) to the central nervous system about how fast and how far a muscle is being stretched. The CNS then sends an impulse back to the muscle telling it to contract, which triggers the stretch reflex.

Question 35

What does the stretch reflex do?

Answer 35

This reflex action that causes the muscle to contract to prevent over-stretching reduces the risk of injury.

Question 36

Where are golgi tendon organs found?

Answer 36

Between the muscle fibre and tendon

Question 37

Where are muscle spindles found?

Answer 37

Lie between skeletal muscle fibres.

Question 38

How do golgi tendons work?

Answer 38

When a muscle is contracted isometrically in PNF, they sense the increase in muscle tension and send inhibitory signals to the brain which allows the antagonist muscle to relax and lengthen.
This is known as autogenic inhibition.

Question 39

How is a PNF stretch performed?

Answer 39

1 – a partner helps you to perform a passive stretch
2 – hold the stretch for 10-12 seconds
3 – perform as isometric contraction
4 – relax and allow the muscle to lengthen during another passive stretch
5 – repeat this process 3 times.