2006-09-06 02:20:11 · 4 answers · asked by Anonymous in Education & Reference ➔ Other - Education
Your muscles require more oxygen when working hard...you breathe heavily & your heart pumps harder & faster to get the oxygen to your muscles.
2006-09-06 02:23:04 · answer #1 · answered by fairly smart 7 · 0⤊ 0⤋
Running increases the need for your cardiovascular system to channel oxygen to the muscles being used. As with all types of excersize, muscles use oxygen, which it turn creates a by-product commonly known as lactic acid. As the intensity or time increases for usage, the heart must beat faster in order to compensate for the lack of oxygen which is being replaced by the lactic acid. In turn, your breathing increases also due to a higher demand of oxygen needed in the bloodstream.
2006-09-06 02:34:09 · answer #2 · answered by Grbrthrxs 1 · 0⤊ 0⤋
To get that blood/oxygen to your muscles and carry away impurities.
2006-09-06 02:25:51 · answer #3 · answered by HoneyBearCub 7 · 0⤊ 0⤋
Simply put, it has to work harder to meet the tissues' oxygen demands.
2006-09-06 02:43:51 · answer #4 · answered by ? 6 · 0⤊ 0⤋