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.

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

**The traditional equation in comparison to the Tanaka equation overestimates HR _{max}in young adults, intersects with the present equation at age 40 years and then increasingly underestimates HR_{max}with 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 HR_{max}(SD ∼10 beats/min), the underestimation of HR_{max}could 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

-ACP

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.

Is the calculation any different for women? This article suggested it is. https://well.blogs.nytimes.com/2010/07/05/recalibrated-formula-eases-womens-workouts/

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

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.”

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

I just wish everyone would read the Tanaka graph above properly and come to the most obvious conclusion.

The important point to take away from this is……

THERE IS HUGE VARIATION BETWEEN INDIVIDUALS OF THE SAME AGE,

..more than enough that least 50% of the population can’t train to HR zones based on any formula for HRmax, unless you do a test you can’t work out if you’re typical or atypical for your age.

The most accessible way to work out your HRmax is to go and do some representative exercises, like a flat out Parkrun or 5x1k intervals, that will give you a real number you can use to back calculate your HRmax from.. i.e. exercises that normally ellicit 90% or 95% of HRmax.

Personally I’m 45, my Max HR is around 193, I’ve certainly seen 190 a few times in sprints at the end of 5ks

Thanks Derek for your thoughts and comments, I concur that we all need to assess our MaxHR individually. I will pass your comments on to the facebook group (it was quite a discussion). Sandi

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.

Great post! There is a third formula that works more accurately for me.

The third calculation uses a formula developed by Dr. Dan Heil after studying 1500 walkers at the University of Massachusetts. This formula calculates MHR using the additional factor of body weight. For men only there is a constant value of 4.5 added to the final result. The formula looks like this for men. Leave off the addition of 4.5 for women:

211.415 – (0.5 * age) – (0.05 * weight in lbs) + 4.5

I found formulas at this website: http://nowlin.com/heartrate.htm

Thanks for explaining the flaws of the 220-age formula