Ajax Bay
Guru
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The formula: 220-age as a useful estimate for HRmax is widely discredited btw (even its originator disavowed it for use in fit people).
The widely (mis)-used common formula was devised in 1970 by Dr. William Haskell, then a young physician in the US federal Public Health Service and his mentor, Dr. Samuel Fox, who led the service's program on heart disease. They were trying to determine how strenuously heart disease patients could exercise.
In preparation for a medical meeting, Dr. Haskell culled data from about 10 published studies in which people of different ages had been tested to find their maximum heart rates. The subjects were never meant to be a representative sample of the population, said Dr. Haskell, who is now a professor of medicine at Stanford. Most were under 55 and some were smokers or had heart disease. On an airplane traveling to the meeting, Dr. Haskell pulled out his data and showed them to Dr. Fox. ''We drew a line through the points and I said, 'Gee, if you extrapolate that out it looks like at age 20, the heart rate maximum is 200 and at age 40 it's 180 and at age 60 it's 160,'' Dr. Haskell said. At that point, Dr. Fox suggested a formula: maximum heart rate equals 220 minus age.
But, exercise physiologists said, these data, like virtually all exercise data, had limitations. They relied on volunteers who most likely were not representative of the general population. ''It's whoever came in the door,''. . . . .it was clear from the scattered data points that maximum heart rates could vary widely from the formula. ''If it says 150, it could be 180 and it could be 120".
But the formula quickly entered the medical literature. Even though it was almost always presented as an average maximum rate, the absolute numbers took on an air of received wisdom in part, medical scientists said, because the time was right . . . . there was a desire for a simple formula to estimate maximum heart rates. Soon, there was a worldwide heart-rate monitor industry, led by Polar Electro Inc, of Oulu, Finland, selling more than 750,000 monitors a year in the USA and citing the ''220 minus your age'' formula as a guide for training. The formula became increasingly entrenched, used to make graphs that are posted on the walls of health clubs and in cardiology treadmill rooms, prescribed in information for heart patients and inscribed in textbooks.
The widely (mis)-used common formula was devised in 1970 by Dr. William Haskell, then a young physician in the US federal Public Health Service and his mentor, Dr. Samuel Fox, who led the service's program on heart disease. They were trying to determine how strenuously heart disease patients could exercise.
In preparation for a medical meeting, Dr. Haskell culled data from about 10 published studies in which people of different ages had been tested to find their maximum heart rates. The subjects were never meant to be a representative sample of the population, said Dr. Haskell, who is now a professor of medicine at Stanford. Most were under 55 and some were smokers or had heart disease. On an airplane traveling to the meeting, Dr. Haskell pulled out his data and showed them to Dr. Fox. ''We drew a line through the points and I said, 'Gee, if you extrapolate that out it looks like at age 20, the heart rate maximum is 200 and at age 40 it's 180 and at age 60 it's 160,'' Dr. Haskell said. At that point, Dr. Fox suggested a formula: maximum heart rate equals 220 minus age.
But, exercise physiologists said, these data, like virtually all exercise data, had limitations. They relied on volunteers who most likely were not representative of the general population. ''It's whoever came in the door,''. . . . .it was clear from the scattered data points that maximum heart rates could vary widely from the formula. ''If it says 150, it could be 180 and it could be 120".
But the formula quickly entered the medical literature. Even though it was almost always presented as an average maximum rate, the absolute numbers took on an air of received wisdom in part, medical scientists said, because the time was right . . . . there was a desire for a simple formula to estimate maximum heart rates. Soon, there was a worldwide heart-rate monitor industry, led by Polar Electro Inc, of Oulu, Finland, selling more than 750,000 monitors a year in the USA and citing the ''220 minus your age'' formula as a guide for training. The formula became increasingly entrenched, used to make graphs that are posted on the walls of health clubs and in cardiology treadmill rooms, prescribed in information for heart patients and inscribed in textbooks.
