Why does your heart rate change depending on what you do?

Hi! Here's your answer!

"Simply put, when it is hot, the body must move more blood to the skin to cool it while also maintaining blood flow to the muscles. The only way to do both of these things is to increase overall blood flow, which means that the heart must beat faster. ... Another important factor affecting exercise heart rate is age."

Hope this helps, and feel free to ask me anything else!

-Edge

answer; i believe that the correct answer is (participation);