Exercise and The Cardiovascular System - GCSE Physical Education (PE) Revision

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During exercise the cardiovascular system works harder to maintain bodily temperature. It also ensures sufficient oxygen delivery to the muscles in order to support aerobic respiration.
Cardiac Output

This is a measure of the volume of blood being pumped per minute. Calculating the cardiac output of an individual is easy; simply multiply the heart rate (no. of heart beats per minute) by the stroke volume (amount of blood pumped by each ventricle on each heartbeat). Then you are left with the cardiac output!

The stroke volume differs from person to person, but the average healthy man will have a stroke volume of 70ml.

Pressure

Blood pressure is, simply, the pressure of the blood against the walls of the vessels. Blood pressure decreases as it travels through the body’s circuit. This is why arteries have a thicker vessel wall than veins, in order to deal with the larger pressure.

This is measured by a sphygmomanometer (sfig-mo-mano-meter) and has two different readings. One for the pressure in arteries when the left ventricle pushes blood out to the body (systolic pressure), and another reading for the pressure of blood in the arteries when this ventricle relaxes (diastolic pressure).