Answer: During vigorous exercise your breathing rate increases in order to intake more oxygen
Explanation: during vigorous exercise / activity the body needs more oxygen in order to produce energy so your breathing rate increases in order to reach the demand of more intake of oxygen , and your muscles work harder due to an increase in oxygen demand and how much oxygen the muscles take from the blood during vigorous exercises , BUT during rest we have normal rate of oxygen intake because your body is at rest at that moment .
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