Constant pressure is required to pump blood through the circulatory system. This ensures the delivery of oxygen and nutrients to and the removal of carbon dioxide and waste products from tissues. Positive pressure is created by forceful contraction of the left ventricle of the heart, measured as systole. It is maintained during relaxation of the ventricle by closure of the aortic valve and recoil of arteries, measured as diastole.
Mean arterial pressure (MAP) is a useful measure of the adequacy of tissue perfusion. It is not a simple average of systolic and diastolic blood pressures. This is because diastole continues for twice as long as systole. MAP can be reasonably approximated using the equation:
In this experiment, you will
- Obtain graphical representation of blood pressure.
- Compare changes in systolic, diastolic, and mean arterial pressures with exercise.
- Use blood pressure readings and pulse to infer changes in cardiac output and peripheral vascular resistance with exercise.