Q:

What is "stroke volume" in medicine?

A:

Quick Answer

Stroke volume is the amount of blood, expressed in milliliters per stroke, that the heart's left ventricle pumps with each contraction. According to Charles Sturt University, total stroke volume is variable, and trained athletes are sometimes able to achieve a stroke volume that is double that of an untrained person.

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Full Answer

Each time the left ventricle contracts, it pushes blood from its interior space through the aorta and out into the body. The amount pumped with each stroke varies depending on the size of the heart, the efficiency with which the left ventricle refills after emptying and the force of the contraction. Regular exercise causes an enlargement of the heart and a strengthening of the cardiac muscle, according to Charles Sturt University. This permits an increase in the total volume the heart is able to pump and reduces the resting heart rate of trained individuals. Calculating the stroke volume is an important step in determining the total cardiac output. An individual's total cardiac output is expressed as the product of the average heart rate multiplied by stroke volume. This gives a figure for how much blood is pumped through the heart every minute and, therefore, how efficiently the cardiovascular system is working to deliver oxygen to the rest of the body.

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