We talked about blood pressure, and changes
in blood pressure with exercise, and now we want to talk a little bit about the oxygen
delivery system, and how your body gets accustomed to exercise, and why this is important. As
you exercise; your body becomes more efficient at delivering oxygen to the tissues. This
represents a red blood cell, and on each red blood cell there are typically four oxygen
molecules. Your hearts job is to deliver those red blood cells to the tissues needed to create
energy. This basically represents that red blood cell, and as you exercise the tissues
become more efficient at utilizing these oxygen molecules, and the tissues also become more
efficient at creating energy from these molecules. That’s important for cardiovascular function.
As you can see in this model, there are blood vessels going to the heart, and the heart
also needs to become more efficient at utilizing these oxygen molecules, because if it doesn’t
have oxygen those tissues will starve and die, just like any other tissue of the body.
As you exercise more, your heart, and all the other tissues of your body become more
efficient at utilizing the oxygen for creating energy. We’re not quite sure of the exact
mechanism of how this works, but we do know that with exercise you get more efficient
at utilizing the oxygen. That’s why athletes have lower heart rates. Their heart doesn’t
have to work as hard to deliver that blood and oxygen to the tissues, because their tissues
have become more efficient at converting oxygen into energy.