ANATOMY

Detailed explanation-1: -The lactic acid needs to be oxidised to carbon dioxide and water later. The creation of lactic acid (which needs oxygen to be broken down) generates an oxygen debt that needs to be repaid after the exercise stops.

Detailed explanation-2: -During anaerobic respiration, lactic acid is produced. This happens when the demand for energy is more and supply of oxygen is less, mainly during heavy exercise. The lactic acid thus formed is broken down by the supply of oxygen.

Detailed explanation-3: -However, if insufficient oxygen reaches muscles but exercise continues, the muscle cells use anaerobic respiration to transfer energy. From the equation, you can see that incomplete oxidation of glucose takes place and lactic acid is produced. The lactic acid builds up and causes an oxygen debt.

Detailed explanation-4: -The amount of oxygen required to remove the lactic acid, and replace the body’s reserves of oxygen, is called the oxygen debt. When someone who has been exercising pays back an oxygen debt, it can take from a few hours for normal exercise, to several days after a marathon.

Detailed explanation-5: -Oxygen debt is a natural, temporary process. When we perform intense exercise, glucose (a sugar that comes from carbohydrates) is broken down to provide energy to our muscles, which produces lactic acid as a result. Oxygen is then used to break down the unwanted lactic acid into carbon dioxide and water.