Is my heart rate dangerous?

I just finished my latest race, and I’m happy with the result. In fact, I reached a new personal best in every metric. I follow a structured training plan and it has really paid off.

However, on the last event my heart rate averaged 181bpm for the 22 minutes of the race, and peaked at 196bpm. At 40yrs old I’m wondering if it is dangerous to push myself that hard. Does anyone know a good resource to investigate this topic?

Thanks for your help.

This is a discussion to have with your doctor preferably with a referral to a sports doctor. There are a lot of variables.


It’s high if you are fit and have good cardio. No matter your age and health issues. However, if you were hammering up hill- did it drop after hammer time? If HR drops efficiently after exertion- then that is a good thing. For me I recognize when I get into proper fit levels and cardio/legs working well- I recover quicker (HR).

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People I know who’ve had heart issues experience an anomalously rapidly elevated HR which doesn’t quickly come back down after a maximal effort is over. It’s where the heart isn’t being properly regulated. If the HR slowly increases, then comes back down, that’s normal. But I’m not a doctor so don’t listen to me.

Everyone has a different maximal HR. The old crusty formulas, especially the one with a slope of 1 BPM/year (ask yourself why would it happen to be exactly 1 bpm/year), are crap.


I have the same concerns - my last race I spent 52 minutes in Heart Rate zone 5.
Yes, I felt like I was working really hard - trying to stay with the bunch.
The races I have done are all pretty similar in terms of spending most time in Heart rate zone 5 - is that normal for these races? or is it a reflection of my fitness (or rather lack of fitness).

Did you set the zones as default or use your known maximum heartrate? Barring any medical conditions extended time in zone 5 should be really hard.
As the others above have mentioned maximum heart rate is highly variable between people at the same age, and can shift a bit as you gain fitness, so you really need to define your own zones.
Any underlying medical conditions however complicate this (and how HRMs read your HR in some cases) so if you have any concerns, and/or things have changed over time, talk to your doctor.


I’m 50 today. Triathlete/runner in my 30’s.

Please don’t extrapolate my story to your body/heart. The electrical system is too complicated.

In my 30’s, I’d race at 205/206 bpm. I asked my physician about it. There were no concerns.

Jump forward to 49…I received an emergent pacemaker.

It’s hard to know if there were electrical issues with my heart in my 30’s. It sure would have been interesting, however, to have been evaluated by a cardiac stress test.

I doubt it would have changed trajectory in health or exercise, but sure would have been insightful.

Not much in the way of answers - but you could ask your physician about the usefulness of a stress test given your health/training questions.

Best of luck! Great job training!

Thanks for the reply. My max heart rate is about 185 - racing on zwift and FTP tests seem to prove that. I think, because I was only just hanging on to the bunch i was effectively doing an all out effort for the entire race duration. In fact most of my races are like that - I guess thats life at the low w/kg end of C grade. It would be nice to race where I can do more than just hang in there. Its crazy the category grading - after 2 DNFs in D and one mid-back pack finish I was “upgraded” to C due to my power… go figure. Maybe my heart is telling me to drop back to D.

Hi Everyone,

I came across a GCN video on this subject today, which I found very useful:

As a result, I’m going to get a check up from a sports cardiologist at some point. Seems like the sensible thing to do.


Great video! Thank you.

Hope your visit goes well.

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This is a complicated question.
I will address 2 questions.

  1. is a fast HR safe.
  2. why we think it is fast based upon heart rate zones.

One reason it is complicated is the previously recognized heart rate zones based on age are very inaccurate.
(220-age) may be a good start for a rough estimate of what your max heart rate is but it’s usefulness ends there.

Your max heart rate is what you measured your heart rate to be.
Whether that is safe or not depends on the circumstance and not the number.
The “circumstance” is - is your heart rate still coupled to your power output.

People who have a tachyarrhythmia (fast pulse due to a conduction issue in the heart) are short of breath and feel weak, frequently even at rest.
If, on your bike, when you put out a hard effort and your pulse goes up, that’s good and normal.
As referenced above, when you back off, your pulse should come down.
Your still coupled and this is safe.

The typical HR zones are garbage.
90,80,70,60 percent of your max HR means nothing and are generally much lower than an individual’s actual zones.
These low numbers cause worry because people feel the are over exerting.
You should take a percentage of your variable or adjustable heart rate.

This is (Max HR- resting HR) X percentage (90,80 etc) + resting HR.
Your HR never goes below your resting HR.
When you take 90% of your max HR, you are subtracting a percentage of your resting HR.
You can never drop your HR to Zero (I know, I see it too!) so your HR zones should only be for range of HR between your resting HR and your max HR. You then have to add the resting HR back in.


Not really directly related, but I’ve found daily monitoring of hear rate to be very useful. I used to race in in my teens and twenties/early 30’s. Now I’m 60. I have data for almost 40 years on myself. One thing that I can tell is when I am sick, overtrained, tired, or have something else going on. Yesterday I was doing some interval type workouts and my max hr rate was 185, well above the 220-age, so that statistic is useless. When I’m racing in Zwift, my hr is normally about 145-160. 10 years ago, my hr would have probably been 125-145 for the same kind of race. My resting is 49. There are no averages. Everyone is born differently and different fitness history.


Also, be mindful of how much caffeine you have before hard efforts. I’ve had a couple interesting episodes when I’ve pushed myself hard to set a Strava PR on a warm day where I’ve had caffeine and my heart rate won’t come down. The first time scared me a bit, and ironically I noticed it when I was at my turnaround point which happened to be a fire station. They did a quick work up on me and after about 15’ it went back down on its own suddenly and was normal. Since then I’ve had some tests done and cleared to work out like normal, but they mentioned it may be wise to limit caffeine on the hard days. I think the key this to look for is noticing if the heart rate matches the effort and does it go up and down how you’d expect.

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I think the most dangerous heart rate is actually zero!