What is meant by oxygen debt?

Oxygen debt refers to the amount of oxygen required to restore the body to its pre-exercise state after intense physical activity. During strenuous exercise, the body may rely on anaerobic metabolism, leading to the accumulation of lactic acid and a temporary deficit in oxygen. After the exercise concludes, the body requires additional oxygen to metabolize the accumulated lactic acid and replenish energy stores, which creates the "debt." Essentially, it highlights the body's need to recover and return to homeostasis.