PULSE RATE

Pulse rate is the number of times the heart beats per minute. It is essentially the same as heart rate and can be measured at points like the wrist or neck. In a healthy individual, the average resting heart rate is about 70 beats per minute. Heart rate can rise or fall depending on the body’s oxygen demands. Key factors influencing this include physical activity, altitude, and environmental temperature.

STROKE VOLUME

Stroke volume is the amount of blood pumped out by the left ventricle with each heartbeat. In other words, every time the heart contracts, a certain volume of blood is ejected into the circulation, and this quantity is the stroke volume. Stroke volume generally remains fairly constant, typically about 70 milliliters per beat.

CARDIAC OUTPUT

Cardiac output refers to the amount of blood the left ventricle pumps into the aorta each minute. It is calculated by multiplying stroke volume by heart rate (pulse rate). In a healthy individual, the average resting heart rate is about 70 beats per minute, and since stroke volume generally remains fairly constant, cardiac output increases in proportion to the heart rate. However, there is a limit to how effective this is—at around 180 beats per minute, the heart does not have enough time to fill properly, causing cardiac output to decrease. At rest, the average cardiac output is approximately 5 to 5.5 litres per minute.

Note: Metabolic rate is the rate at which the body uses energy to maintain its functions and carry out activities.