Question

What type of respiration takes place in human muscles during vigorous physical exercise? Give reason for your answer.

Answer 1

During vigorous exercise, your muscles demand energy faster than your circulatory system can supply oxygen, creating a temporary oxygen deficit. To maintain rapid energy production under these low-oxygen conditions, muscle cells switch to an emergency anaerobic pathway that partially breaks down glucose without oxygen. This process converts pyruvate into lactic acid, yielding a quick but limited amount of energy (2 ATP per glucose). The accumulation of lactic acid alters muscle pH, resulting in temporary fatigue and painful cramps until oxygen delivery is fully restored.