AP BIOLOGY

Detailed explanation-1: -When you exercise and your muscles work harder, your body uses more oxygen and produces more carbon dioxide. To cope with this extra demand, your breathing has to increase from about 15 times a minute (12 litres of air) when you are resting, up to about 40–60 times a minute (100 litres of air) during exercise.

Detailed explanation-2: -Your blood picks up oxygen as it travels through your lungs and delivers it to the muscles you’re using. As your level of activity increases, your breathing rate increases to bring more air (oxygen) into your lungs so that your lungs can pump more oxygen into your blood and out to your muscles.

Detailed explanation-3: -During vigorous exercising, more ATP is required for cellular respiration. Hence the breathing rate increases during vigorous exercising.