What Should Your Maximal Exercise Heart Rate Be?: The Importance Of Using The Right Age-Predicted HRmax Formula

A reader who runs 5Ks posted a question recently which indicated concern that his heart rate during intense exercise was much higher than his age-predicted heart rate.  He writes

I’m 65, exhaustion HRmax is 188, HRave for 5k is usually 152-154 and interval HRmax is usually 175-179 depending on how hard I push”

He wondered if he should be concerned about being a “high-beater.”

This prompted the skeptical cardiologist to examine the literature on age-predicted maximal heart rate which led to the shocking discovery that the wrong formula is being utilized by most exercise trainers and hospitals.

First , some background.

The peak heart rate achieved with maximal exertion or HRmax has long been known to decline with aging for reasons that are unclear.

The HR achieved with exercise divided by the HRmax x 100 (percentage HRmax) is widely used in clinical medicine and physiology as a basis for prescribing exercise intensity in cardiac rehab programs, disease prevention programs and fitness clinics.

During stress tests we seek to have patients exercise at least until  their heart rate gets to at 85% of HRmax.

The Traditional Formula For HRmax

The formula that is widely used for HRmax is

HRmax = 220-age

It appears to have originated from flawed studies in the early 1970s. These studies included subjects with cardiovascular disease, smokers and patients on cardiac medications.

The Improved HRmax Formula

Tanaka, et al in 2001 performed a meta-analysis of previous data on HRmax along with accumulating data in their own lab. This was the first study to examine healthy, unmedicated, nonsmokers. In addition each subject achieved a verified maximal level of effort as documented by metabolic stress testing.

Their analysis obtained the regression equation (which I term the Tanaka equation)

HRmax = 208-(0.7 x age) 

Below is the graph of the laboratory measurements from which the regression equation was obtained.

Relation between maximal heart rate (HRmax) and age obtained from the prospective, laboratory-based study.(Tanaka, et al)

This graph shows how  inaccurate the traditional equation is, especially in older  individuals like my reader:

Regression lines depicting the relation between maximal heart rate (HRmax) and age obtained from the results derived from our equation (208 − 0.7 × age) (solid linewith 95% confidence interval), as compared with the results derived from the traditional 220 − age equation (dashed line). Maximal heart rates predicted by traditional and current equations, as well as the differences between the two equations, are shown in the table format at the top.(from Tanaka, et al)

The traditional equation in comparison to the Tanaka equation  overestimates HRmaxin young adults, intersects with the present equation at age 40 years and then increasingly underestimates HRmaxwith further increases in age. For example, at age 70 years, the difference between the two equations is ∼10 beats/min. Considering the wide range of individual subject values around the regression line for HRmax(SD ∼10 beats/min), the underestimation of HRmaxcould be >20 beats/min for some older adults.

There are likely lots of perfectly healthy individuals in their sixties and seventies then who have heart rates at maximal exertion that exceed by 10 to 20 beats per minute the HR max predicted by the traditional formula.

This is due to a combination of the inaccuracy of the traditional formula and the wide variation in normal HR max at any given age (standard deviation (SD) of approximately 10 beats/min.)

Thus, my reader at age 65 would have a HRmax predicted by the Tanaka equation as

208-0.7 x 65=162

If we allow for a 10 BPM range of normality above and below 162 BPM we reach 172 BPM which gets close to  but doesn’t reach the reader’s 188 BPM.

If you examine the scatterplot of the Tanaka data you can see that several of the points for age 65 reach into the 180s so chances are my reader is still within normal limits

The Bottom Line on HRmax

The widely used traditional formula for predicting HR max is inaccurate.

Athletes, trainers, physicians and hospitals should switch to using the superior Tanaka HR max formula.

Individuals should keep in mind that there is a wide range of HR response to exercise in normals and variations of 10 BPM above and below the predicted response are common and of no concern.

Chronotropically Yours


Addendum. The 220-age formula is so heavily etched into my brain that I used 220 instead of 208 when I initially calculated the predicted max HR for my reader. this has been corrected.Thanks to Chris Sivewright for pointing this out.

6 thoughts on “What Should Your Maximal Exercise Heart Rate Be?: The Importance Of Using The Right Age-Predicted HRmax Formula”

  1. Is it true that well-trained masters athletes in many instances have low maximum heart rates — significantly lower than the Tanaka calculation?

    1. In the Tanaka paper they note
      “Moreover, consistent with the present findings, gender (14)and habitual physical activity (16)do not appear to influence intrinsic heart rate in humans. These results collectively suggest that a decrease in HRmaxwith age may primarily be due to the reduction in intrinsic heart rate.”

  2. This post sparked lots of comments from my Facebook group Running after 60. Some preferred the HR max=220-(age/2) was a better formula. Others felt Tanaka underestimated HR for well trained runners. There was also citation from Larisa Dannis’ racer story. She used the MAF method (Phil maffetone’s 189 formula).
    What are your thoughts for us 60+ athletes

  3. Thanks – Great reference paper. I couldn’t access one, or understand the second paper Tanaka, et. al used for “the rate of decline in HRmax observed in the present study is very similar to that reported previously for intrinsic heart rate determined after cardiac autonomic blockade (-0.6 -0.8 beats/min per year) “

    Using Tanaka HRmax(55) for the year I did the HRmax=188 tests puts me +18 bpm over the mean. If I use Tanaka HRmax(65) + 18 bpm for a prediction of my HRmax today, it comes to 181. Using -0.7 beats/min per year for 10 years after the measured 188, also would predict HRmax now of 181.

    Using this HRmax of 181, seeing 174-179 in my tough intervals would be 94%-98% of my HRreserve (HRrest: 55), which sounds like I might be pushing just a little too hard. (The exercise HRmax seen appears dependent on the outside temperature and inversely related to how rested I am. Florida had the hottest February on record.)

    Hopefully, my goal of regaining the ability to run 5k is achievable. My time was always “poor”, but five years ago I was doing it until a bad tennis injury knocked me off my feet.

    Thanks for all your informative posts – keep them coming.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s