How is blood flow related to lung function during exercise?

Blood vessels are dilated to increase the amount of oxygen carried in the blood, and the lungs work harder to meet the body's oxygen demands.
   
Blood volume increases during exercise, making the body more efficient, so it is not necessary for the lungs to work as hard.
   
The lungs determine the speed at which the heart pumps, so blood flows at a level that accommodates oxygen absorption in the muscles.
 
The lungs expand and contract, which increases the rate of blood flow so the muscles can

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How is blood flow related to lung function during exercise?

The way that this two are related is the during exercise your heart starts to pump much faster increasing the blood flow for a faster exchange of oxygen. This happens since your muscles require more oxygen therefore you start breathing faster to put more oxygen in your blood which is then circulated throughout your body.

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