#5.3 u3aos2 - acute muscular responses to exercise

Question 1

acute response
3 marks

Answer 1

short term
lasts only for the duration of the activity
and duration of the recovery

Question 2

what are the three acute physiological responses to exercise
3 marks

Answer 2

respiratory
cardiovascular
muscular

Question 3

muscular
2 marks

Answer 3

the body system responsible for producing movement
by contracting muscles

Question 4

what are the six muscular responses to exercise?
6 marks

Answer 4

• increased motor unit recruitment
• increased used of fuels and energy substrates (decreased fuel stores)
• increased muscle temperature
• increased blod flow to working muscles
• increased arteriovenous oxygen difference (avO2 difference)
• increased enzyme activity

Question 5

motor unit
2 mark

Answer 5

a single motor neuron
and all the muscles fibres it can sitmulate

Question 6

motor neuron
2 marks

Answer 6

a nerve cell
that carries motor signals/info away from CNS towards the muscles.

Question 7

why does motor unit recruitment need to increase?
2 marks

Answer 7

when physical activity increases
the amount of force developed by the working muscles need to increase too.

Question 8

how does increased motor unit recruitment increase performance?
4 marks

Answer 8

the brain either:
- increases the amount of motor units recruited
increased motor units recruited = increases amount of force production by the muscles in the body.

• increases the frequency of messages sent to the motor neuron.
  increased frequency = increased repitition of muscle contractions, leading to more frequent and more force production.