Oxygen debt is a term used to describe exertion which causes an increase in lactic acid production. A trained athlete is able to increase the oxygen consumption in their muscles to a greater degree than non-athletes. Thus a trained athlete will have a lesser degree of oxygen debt for an activity that they have trained for in comparison to a non-athlete. The increased production of lactic acid (and hence lowering of pH) leads to eventual termination of a particular activity.
Last reviewed 01/2018