If you use them more as in exercise your lungs will get used to inflating more when you breathe and they will transfer more oxygen into your bloodstream so your heart wont need o send as much blood to your muscles for respiration.
it it healthy
When you are exercising your heart rate goes up, because your heart is pumping faster.
Like any muscle, your heart works best with routine exercise. Being active also reduces stress, lowers your cholesterol, and helps you lose weight. Before you start exercising, talk with your health care provider.
exercising,walking,eating.......
Exercising
To compensate for the body requiring more oxygen because of exercising
i actually just saiyin that you can search the resting heart rate and maybe it'll show the exercising one
They are in fact closely linked, even more so than the brain is linked to other parts of the body.
Your Heart
Aside from taking medication there are many ways to help your heart. Some big one's are not smoking, exercising daily, and maintaining a healthy diet/weight. Regular checkup's are also critical.
Of course exersizing increases heart rate
Well the heart is a muscle meaning that when you use the muscle it will get stronger.