Oxygen debt is a certain amount of oxygen required by muscle cells to oxidize lactic acid produced as a result of anaerobic respiration, to
During some strenuous muscular activity, the oxygen is not supplied to the muscles as fast as it is needed. So, the muscles cells start to carry out anaerobic respiration along with aerobic respiration building an oxygen dept . Thus in the absence of oxygen, there is incomplete broken down of glucose into lactic acid.
Lactic acid is something that causes muscles' soreness and fatigue. So, it must not reside in muscles for longer time. Thus, oxygen dept must be repaid.
Thus, at the end of the activity, when there is enough oxygen; lactic acid is oxidized to