1. Acute Cardiovascular responses
All of these responses are aimed at getting more blood, oxygen & fuels to working muscles and speed up removal of wastes.
↑ Stroke Volume (ml of blood pumped out of the left ventricle per beat)
↑ Heart Rate (beats per minute)
↑ Cardiac Output (litres per minute) = SV x HR
Robert Malpeli - Balwyn High School 2010

2. Robert Malpeli - Balwyn High School 2010

3. Robert Malpeli - Balwyn High School 2010
↑ Blood pressure (mainly systolic)
↑ Venous return to heart (assisted by muscle pump, respiratory pump and venoconstriction – still approx 4% but 5 times as much blood compared to rest)
↓ Blood volume (plasma loss)
↑ Blood directed towards working muscles (vasoconstriction of arterioles supplying inactive muscles reduces blood flow here and vasodilation of arterioles supplying muscles increases blood flow here)
Robert Malpeli - Balwyn High School 2010

4. Acute Muscular responses
↑ Increased blood flow to working muscles
↑Motor unit / fibre recruitment
↓ Fuel stores (PC, ATP, glycogen, triglycerides)
↑Lactate production (then ↑ H+ if not removed)
↑ Muscle temperature
↑ Oxygen Consumption
Robert Malpeli - Balwyn High School 2010

5. Robert Malpeli - Balwyn High School 2010
↑ Arteriovenous oxygen difference (a-vO2 diff)
The greater the extraction of oxygen by working muscles, the greater the a-vO2 diff
Robert Malpeli - Balwyn High School 2010

6. Robert Malpeli - Balwyn High School 2010