The Neuromuscular System

Question 1

What is the function of the autonomic nervous system?

Answer 1

To regulate the function of our internal organs and to control our skeletal muscles.

Question 2

How does the autonomic nervous system work?

Answer 2

It works autonomously.

Question 3

What are the types of muscle fibres?

Answer 3

Slow oxidative (type 1)

Fast oxidative glycolytic (type 11a)

Fast glycolytic (type 11x)

Question 4

What is the function of slow-twitch fibres (type 1)?

Answer 4

These muscle fibres have slow contraction speed and are better adapted for low-intensity exercise like long-distance running. These produce their energy aerobically.

Question 5

What is the function of fast-twitch fibres (type 11)?

Answer 5

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

Question 6

What is the function of fast oxidative glycolytic fibres (type 11a)?

Answer 6

these muscle fibres are more resistant to fatigue and are used in events such as 1500m where long bursts of energy are required.

Question 7

What is the function of fast glycolytic fibres (type 11x)?

Answer 7

These muscle fibres fatigue much quicker than type 11a and are used for high explosive events such as 100m where a quick short burst of energy is needed.

Question 8

What is hypertrophy?

Answer 8

Where the muscle has become bigger and stronger.

Question 9

What is a motor unit?

Answer 9

A motor neurone and its muscle fibres.

Question 10

What is a motor neurone?

Answer 10

A nerve cell which transmits the brain’s instructions as electrical impulses to the muscles.

Question 11

What is a neuromuscular junction?

Answer 11

Where the motor neurone and the muscle fibre meet.

Question 12

What is the all or none law?

Answer 12

Once the motor neurone stimulates the muscle fibres and either all of them will contract or none of them will contract. It is not possible for a motor unit to partially contract.

Question 13

How can the strength of contraction be increased?

Answer 13

Wave summation and spatial summation.

Question 14

What is wave summation?

Answer 14

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

Question 15

What is the spatial summation?

Answer 15

When the size of contraction changes by altering the number and size of the muscle’s motor units.

Question 16

What is proprioceptive neuromuscular facilitation (PNF)

Answer 16

This is an advanced stretching technique, it is considered as one of the most effective forms of flexibility training.

Question 17

What are the names of the mechanisms that help regulate muscle action in PNF training?

Answer 17

Muscle spindles

Golgi tendon organs

Question 18

What is the role of muscle fibres in PNF training?

Answer 18

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

Question 19

What is the role of the Golgi tendon organs in PNF training?

Answer 19

These are activated when there is tension in a muscle.