Why do
your heartrate change?

Your heart rate or rhythm can change when you are under stress or having pain. Your heart may beat faster when you have an illness or a fever. Hard physical exercise usually increases your heart rate, which can sometimes cause changes in your heart rhythm.

Your heart rate or rhythm can change when you are under stress or having pain. Your heart may beat faster when you have an illness or a fever. Hard physical exercise usually increases your heart rate, which can sometimes cause changes in your heart rhythm.

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