lecture 8 Flashcards
1
Q
resting SV values during exercise
A
untrained: 70mls
trained: 100mls
2
Q
exercise SV values:
A
untrained: 110mls
trained: 180mls
3
Q
Mechanisms to increase SV during exercise
A
1- increased blood back to the heart
2- normal ventricular filling, followed by a forceful contraction
3- training adaptations
4
Q
factors which have an intropic effect
A
1- autonomic NS activity
2- hormones
3- change in ion concentrations
5
Q
Response to prelonged exercise
A
Cardiovascular drift
- SV volume gradually decreases (due to overheating)
- HR increases due to SV decreasing. Maintain cardiac output
- blood flow directed to skin to decrease heat
6
Q
Cardiac ouput
A
the amount of blood pumped by the heart (L/min)
= HR x SV
7
Q
Q during exercise
A
increases to match the need for increased oxygen supply
- resting: Q = 5-6L/min
- Sedentary: Q = 20-22L/min
- Athlete: Q = 35-40L/min
8
Q
HR response to exercise
A
rapid, due to the anticipatory response increase stimulated by a centeral command
- parasympathetic decreases
- sympathetic increases
9
Q
what is HR controlled by during exercise
A
catecholamine release
