Definitions for "Oxygen debt"
the way we pay back oxygen deficit built up during anaerobic exercise, once exercise stops.
depletion of oxygen stored in the tissues and red blood cells due to a burst of exercise. Oxygen is restored after the exercise is completed. Although the other tissues can accumulate an oxygen debt, it is essential for the brain to maintain its oxygen supply (New Scientist). WBD, L-Z, p 1489, 1979.
Meaning "out of breath". It's a deficiency of oxygen in working muscleswhen performing exercise that is so demanding the cardiovascular system cannot deliver oxygen fastenough to the muscles to support aerobic metabolism. The debt must be repaid by rapid breathing afterthe activity slows down or stop. Oxygen debt leads to anaerobic metabolism, which leads to lactic-acidbuildup and muscle fatigue.
The amount of oxygen needed to recover from physical activity.
cumulative deficiency of oxygen that developes in the body during periods of intense activity and must bemade good when the body activity returns to normal level. In patients with severe pulmonary insufficiency, climbing a step or two can be considered 'intense activity'.
Keywords:  inducing, heavy, thus, greater, demand
A state where the energy demand is greater than what can be provided by oxygen thus inducing heavy breathing to consume more oxygen