As we all know, any kind of exercise requires that you use some form of energy. When you think of aerobic and anaerobic exercises, you should really think of them in the mind frame of the presence of oxygen. In aerobic exercises, your body is using oxygen to create energy (Callaway, 2011). In anaerobic exercises, your body is using everything but oxygen to create energy (Callaway, 2011). Strictly speaking, the terms "aerobic" and "anaerobic" refer to the presence and absence of oxygen, respectively. Most of our cells prefer to get their energy by using oxygen to fuel metabolism. During exercise with adequate fuel and oxygen (i.e., aerobic), muscle cells can contract repeatedly without fatigue. During anaerobic or non-oxygen conditions (i.e., higher intensity exercise), muscle cells must rely on other reactions that do not require oxygen to fuel muscle contraction. This anaerobic metabolism in the cells produces waste molecules that can impair muscle contractions.
The problem with the terms "aerobic" and "anaerobic" when applied to exercise is that we actually never swit ch from total aerobic to total anaerobic metabolic conditions. In reality, the more intensely we exercise, the greater the need for anaerobic energy production. Consequently, it is best to view the