There are two main forms of respiration that are used during exercise. These are known as aerobic and anaerobic respiration. First of all, respiration has to do with whether or not there is enough oxygen present during exercise. If there is enough oxygen present, then this is known as aerobic respiration; if not, then this is known as anaerobic respiration.
During the process of aerobic respiration, the oxygen in the cells produce carbon dioxide, water, and energy (ATP). The carbon dioxide leaves the body as one exhales, the water as sweat and urine, and the energy is what allows a person to keep exercising for an extended amount of time. When the body is engaged in aerobic respirations, each molecule of glucose produces 38 molecules of ATP. That’s a lot of energy!
This is one place where aerobic and anaerobic respirations differ. When oxygen is not as abundantly available, and there is not enough to produce the amount of energy (ATP) to sustain a long period of exercise, this is known as anaerobic respiration. In this type of respiration, the cells do not have enough oxygen, and end up producing a considerably lesser amount of energy (ATP). In fact, each molecule of glucose produces about 2 molecules of ATP during anaerobic respirations. Also, instead of producing a lot of carbon dioxide and water, anaerobic respirations produce lactic acid. This lactic acid can build up in muscles and cause soreness.
There are many different exercises that use mostly one or the other of these two types of respirations. Exercises that require endurance, and energy being produced for an extended period of time use aerobic respirations. Some examples of these are: running/jogging, swimming, riding a bike, etc. On the other hand, exercises that are usually more physically intense, and cannot be continued for a very long time, usually involve anaerobic respirations. This is because there is not enough Oxygen in the cells to produce the needed energy to continue these exercises for very long. Some of these exercises include: weight lifting, intense sports, sprinting, etc.
Regardless of how different both of these types of respirations are, they still both produce ATP; one (aerobic) just produces more energy (ATP) than the other (anaerobic). Also, most of the time, a person does not just use one or the other type of respiration when they are exercising. Some sports and exercises require aerobic respirations, while also demanding times of anaerobic respirations.