Question
I've read articles about heart rates of active and inactive people, but they seem to have major flaws. One claimed that because active peoples' resting rate is so much lower their total heart beats per day is much less. The calculation used a higher rate for an exercise period of 40 minutes per day, and a lower rate for the rest of the day.
This seems to forget that heart rate doesn't switch from high to low without a transition. Also, active and inactive people do other things during the day that raise their heart rates.
How important is the heart rate of people who exercise?
Answer
The article's conclusion is correct although any estimates can only be approximations. The average person circulates about 4.9 liters (nearly five quarts) of blood per minute. With each beat your heart pumps about 70 milliliters (half a cup) of blood.
With a resting heart rate of 70 beats per minute, you circulate 70 times 70, which is 4,900 milliliters (4.9.liters) per minute.
If you are aerobically fit, your heart becomes more efficient. Say it can pump 85 milliliters per beat. You can now circulate the same volume of blood with only 58 beats per minute (58 times 85 is 4,930 milliliters).
When you stress a body system and let it recover, it grows stronger. If you stress your heart with exercise, during recovery it grows stronger. A stronger heart muscle can pump more blood with each beat, and pump the same amount of blood per minute by working less hard, that is by slowing down.
The well-conditioned person not only has a lower resting heart rate, they have a lower heart rate for all their activities, compared to someone who is unfit. If a fit person is sitting down reading and then gets up and climbs a flight of stairs, their heart rate increases. But it will still be lower than that of someone who is out of shape who does the same thing.
It is true that the exerciser will have a period of increased heart rate while they are working out. But no matter how fit you are, you spend most of each 24 hours not exercising.
During this time your heart will be slower than that of an inactive person, and this is what makes the difference. Overall then, the active person has fewer heart beats per day than an inactive person.
Learn more ways to use your heart rate monitor to improve fitness.