when blood passes through cold muscles, oxygen in the blood can’t detach itself from its hemoglobin very easily. it’s as if the oxygen says, “it’s too cold in there. i’m staying right here in the blood with my hemoglobin buddy.” as muscle temperature rises, oxygen breaks away from the hemoglobin more rapidly and more completely. if you plunge into an activity without warming up, your “cold” muscles are, in effect, short of oxygen for the first few minutes. you’ve probably experienced this although you may not have understood it. there may have been days when you hadn’t had time to warm up, and the first ten minutes of jogging got you out of breath. essentially it’s because ______________________.

① your muscles lacked oxygen -정답

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