Question

A person reached a specific distance once on feet on once by running in which situation his legs pain why?

Answer 1

while running his legs pain because carbondioxide will increases in his leg muscles

Answer 2

His leg muscles will pain while he is running, because lactic acid builds up, and they also  get stretched, and so do the leg muscles, which causes pain. Your legs may hurt after a day or two after running, because they are making the adjustment to your new activity.

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