The blood vessels dilate to increase the "blood traffic" through the lungs to carry more oxygen to the muscle. The lungs work harder (faster respiratory rate) to increase the rate of oxygen/carbon dioxide exchange in the lungs.
There are four _______ in planning an exercise program.
Answer: Out of all the options that are presented above the one that completes the statement and makes it true is variables. Therefore: There are four variables in planning an exercise program. Frequency, mode, intensity, and duration.
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Answer:
the temperature rise becoming a fever that are caused by chemicals called pyrogen falling the bloodstream to fight off infections