Yesterday, when Eric returned home from jogging, he was breathing heavily, sweating profusely, and complained that his legs ached and felt weak. He took a drink of Gatorade and took it easy until he could “catch his breath”.

He is come to clinic today to ask you the following questions to explain what happened to him:

A. Why was he breathing heavily (hint–mention what ATP harvesting pathway his working muscles had been using that lead to such heavy breathing)

B. Why were his muscles so sore and feeling weak (hint- mention what metabolic product(s) could account for this).