By-Products of Aerobic Exercise

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According to the American Sports Medicine Institute, aerobic exercise includes activities that are done continuously for at least 15 to 20 minutes and at an intensity of 70 to 90 percent of your maximal heart rate. This includes workouts like jogging, swimming and biking. The energy process that occurs during aerobic exercise to provide your body with the fuel it needs also creates a couple of by-products.

Energy Process During Aerobic Exercise

For your body to participate in aerobic activities, it must efficiently provide your working tissues with oxygen. Oxygen is an essential component during the process when your body converts fat and glucose, which you’ve received by eating food, to a usable energy source that your tissues can then use. This usable energy source is called adenosine trisphophate, or ATP. Throughout the process of creating ATP, your body also creates a couple of by-products, which it must then effectively get rid of to keep the process going.


The two by-products created during the energy process of aerobic activities are carbon dioxide and water. Three products are created during ATP conversion, including Acetyll-CoA, which is a form of acetic acid, as well as water and carbon dioxide. The Acetyll-CoA then goes on to finalize the conversion of ATP, but the water and carbon dioxide provide no additional function.

Getting Rid of By-Products

Both the water and carbon dioxide molecules enter your blood stream. The water remains and increases blood volume. Carbon dioxide molecules, however, eventually travel up to your lungs and are then expelled from your body when you exhale. Just as your effectiveness at breathing in oxygen and delivering it to tissues makes a significant impact on your athletic performance, so does your ability to get rid of carbon dioxide and water from the ATP conversion site. As you consistently participate in aerobic activities, your body will become more effective at getting rid of the by-products.


If you increase your exercise intensity to a level where your heart is beating faster than 90 percent of your maximum heart rate, your aerobic system will no longer able to keep up with the energy demand of your tissues. Therefore, it will begin the anaerobic respiration process to get your tissues the ATP they need more quickly. The anaerobic system is significantly faster than the aerobic system because it doesn’t require the presence of oxygen, but it has a limitation on the amount of ATP it can create.