The Neuromuscular System

Question 1

Describe the slow twitch muscle fibres (type 1)

Answer 1

Contracts against low resistances for extended periods of time
Equipped to resist fatigue and sustain activity at low-moderate intensity
E.g. endurance events

Question 2

Describe the fast oxidate glycolytic muscle fibres (type 2a)

Answer 2

Share both type 1 and type 2 characteristics.
Useful for a range of intensity and durations will prefer this due to there versatility
E.g. Game sports

Question 3

Describe the fast glycolytic muscle fibres (type 2b)

Answer 3

Greatest amount of anaerobic capabilities. Can generate high amounts of force very quickly.
Not good for aerobic respiration as limited capillary network and mitochondria count

Question 4

Describe motor units

Answer 4

A motor unit is described as a single motor neurone and all of the muscle fibres. A motor unit can contain anywhere between 10 and thousands of muscle fibres. Muscles that produce large powerful movements contain motor units with large numbers of fibres.

Question 5

Describe the all of none law

Answer 5

Means a fibre can be contracting it not contracting, no middle ground.
To alter the contractile force, the CND will need to innervate different combination of of motor units that equal required level of force for movement

Question 6

What is the spatial summation theory

Answer 6

If initial impulse wasn’t good enough to innervate a more unit, this can begin leading to an eventful contraction.
It’s the additive effect of new impulses arriving at the neuromuscular junction, building the strength of the action