Question

why do we get muscle cramps after heavy exercise

Answer 1

due to anaerobic respiration or collection of lactic acid after a long exercise or physical activity.

Answer 2

when an aerobic respiration takes place in our muscles and glucose is converted into lactic acid because of the lack of oxygen. Muscle cramps are caused. They can be relived by hot water bath or massage because this increases the blood circulation which increases the supply of oxygen.
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