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B2 1 Interpreting data on breathing rate and heart rate

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Answers to interpretig breathing and heart rate

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Cardiovascular System: Control of Heart Rate

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Therefore a 20-year-old person will have a maximal heart rate of about 200 beats/min, and this will decrease to about 170 beats/min when the person is 50 years of age. This maximal heart rate is genetically determined and cannot be modified by exercise training or by external factors.