Exercise pt 1

Question 1

What are the changes in BF during exercise?

Answer 1

Active skeletal muscle and heart muscle
Brain
Skin
GIT, kidneys and other organs

Question 2

Active skeletal muscle and heart muscle

Answer 2

Increased BF
Locally controlled arteriolar vasodilation (active hyperaemia)
Reinforced by epinephrine in these tissues

Question 3

Brains

Answer 3

Blood flow increases by 25-30%

Question 4

Skin

Answer 4

BF Increase with prolonged exercise
Hypothalamic temperature control = skin Arterioles vasodilatory
Heat generated by skeletal muscle is lost to the environment
Norepinephrine - a1 receptors - generalised vasoconstriction
Epinephrine - a1 and b2 receptors
Activation of b2 receptors causes vasodilation

Question 5

GIT, kidneys and other organs

Answer 5

BF decreases

Sympathetically induced arteriolar vasoconstriction Via a1 receptors

Question 6

What are the proposed causes of increased ventilation?

Answer 6

Proprioception
Increased body temperature
Adrenaline
Cerebral cortex

Question 7

Proprioception

Answer 7

Afferent impulses sent to chemoreceptors

Joint and muscle receptors stimulated during exercise

Question 8

Increased body temperature

Answer 8

Stimulate RCC

Body temperature rises during exercise

Question 9

Adrenaline

Answer 9

Cause an increase in sympathetic activity - increase in epinephrine
Adrenal medullary hormone stimulate RCC to increase ventilation

Question 10

Cerebral cortex

Answer 10

Feed-forward regulatory mechanism

Motor region of brain increases ventilation and circulation