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Sustained High Heart Rate During Exercise


#1

I am fit, active and old… 56yo. I do all kinds of exercise and activities and maintain a high level of fitness all year. Being 56, my estimated max HR is 200-56=164. Over the years, my max HR has tracked this MAX HR pretty well during HIIT.

I am still doing the same activities that I was doing when I was 30; skiing, lifting, hiking, Mountain biking. And with nearly the same intensity.

RIght now, I am mountain biking a lot. I have a trail that I ride several times a week. It is 1400 vertical feet of climbing over 3.5 miles at moderately high elevation (5000ft). I ride to get up as quickly as possible. Yesterday’s ride was completed in 42 minutes. A good number for me at this point in the season.

My heart rate was 170 Max and 159 average. The Max number is not a concern. The average number means I sustained an average of 97% of typical Max HR for 42 minutes.

Over the years, I have read articles advising against sustained high heart rate during exercise. Just curious if anyone here has strong opinions (for or against) the kind of exercise I am doing… at my age and even older… I have no plans to stop.


#2

This worries me as well, somewhat. I’ve read so much conflicting research/opinions on it, and i’ve seen so many healthy older athletes, but also hear stories about people who need pacemakers etc, so no idea really.

My takeaways from it are: very frequent sessions at threshold can cause desensitization of barorceptors (or something) in the heart etc. It’s the constant grinding away at threshold pace/HR that can permanently desensitize these receptors, cause chronically low HR & more stress etc.

On the flipside, infrequent sessions at threshold are fine. You stress the heart, but you give it time to recover, you’re good.

For me personally, this means training mostly at low percentages of my max HR, below aerobic “zones”. For me @ 35, that’s anywhere from 100-139. I try to keep most of my training there, especially towards the left end of it (110-120 BPM). I don’t feel any “heart stress” in these zones. If I run daily at 145-170 BPM, I can “feel” the toll it takes on my heart/cardio system. I’ve trained like that, I end up feeling like crap. So now I do lots of “ultra light” training/mileage (running), and infrequent speed/racing. Since I train mostly 2x/day now, that’s 11-12 sessions at “easy” effort, 2-3 at hard effort (threshold+, speed/racing).

I also think bodyweight has alot to do with it. I hear more stories of people having cardiac problems later on in life, from training too hard, but previously being out of shape. So people going from “weak base” to “warrior status” with lots of extra weight. The more muscle & fat you have, the harder it is for your heart to work and pump blood throughout, so I feel like this is a pretty significant factor that people rarely talk about. ie, I feel more comfortable being extremely light & putting in lots of mileage, than if I were heavier putting in less mileage.

Then there’s the “yolo” side of things. If you just love it and dgaf, then none of this even matters.

I’d personally look at it from a hunter/gatherer standpoint though, that’s how I approach things. If every day you are struggling to survive, you’re going to die sooner (I imagine). Just seems like “darwinism”. If however, you are comfortable 5 days a week, and “hunt” (push the limits) 2 days a week, just seems alot healthier. That’s some serious evo-bro stuff but it makes sense to me.

peace!


#3

Thanks for the info.

I maintain this physical lifestyle and feel fine. No stress or ill effects of any kind. Have always been either lean or skinny… never fat.

One issue I will now mention is this… a thickening of my heart walls. I had an echo-cardiogram performed last summer. The cardiologists explained that my heart walls were thicker than normal. Could be from disease or from extreme exercise.

He didn’t like the thick walls and recommended against my fitness regime.

Now, we exercise to make our muscles stronger and more efficient… and bigger. I certainly work my biceps to increase their size.

So, I should expect that my heart responds to my exercise by getting stronger, more efficient, and perhaps even bigger.

You brought up a good point about recovery. I don’t feel the need to do less, but I be more conscious about heart recovery after such exercise. That’s it… no more than every other day!

Thanks


#4

Your cardiologist is looking at cardiac hypertrophy as the issue, and not looking at the cause to it. If you have been doing as much cardio-intensive work as you say, then of course you are going to see some hypertrophy in the heart tissue. There is a difference between the two (exercise induced vs disease induced), and how they manifest symptom-wise. Which brings up the question:

Why did you have the echo done? Is that a preventive test they start administering after a certain age, or was your doc concerned with something else he was seeing (lab results, etc)?

I’ve had both echocardiograms and stress echo tests done in my thirties while in the military, because an EKG (flight physical) showed an abnormality. Turned out to be nothing, apparently my heart sits more centered and upright than the average so a 12-lead will throw codes occasionally. Point being, if you are not suffering any symptoms and the only reason you know about your thickened walls (again, common in athletes) is from this random test (with no other ill signs or symptoms), I would say not to worry about it. Just keep doing what you are doing, until/unless you are feeling symptoms - then definitely dial it back.

Caveat: I am not a doctor, I have just read a lot about this (strength and conditioning). You know your health history, you know your fitness history, you know what symptoms you are (or are not) experiencing. You have your doc telling you one thing and a random guy on the web telling you something else. You have to make that call. I will also mention though, your doc said he doesn’t like your fitness regimen because it may be thickening your heart walls, or he doesn’t like it because you have thickened heart walls? With no other symptoms (sorry, dead horse), there’s no reason to be concerned with thickened heart walls.


#5

And just to throw it out there, adarqui and I just happened to have a convo about max hr a while back. The formula you are using is outdated and very inaccurate. Try this one:

211-(.64 x age)
For you: 211-(.64 x 56) = 175

From a Norwegian study, claims to be more accurate (although there is still a margin of error, something like 10-20 bpm).


#6

Because of a repeatable pattern. I have wanted an echo because I know I am operating outside of what is normal and have been doing this for about 8 years. But, the expense subdued my curiosity. Every season, I ski until mid-April and then wait for the snows to melt and the trails to dry out. About 8 weeks of little cardio and more weight lifting. In Mid April, I hit the mountain trails hard.

The first 4 or 5 rides will take me nearly 55 minutes to make the climb. I sometimes experience chest pain about 3/4 into the ride. The pain is right on top of the heart. I know I am not having a heart attack, but I will either end my ride or I will continue up at a reduced effort.

I believe this pain is my chest muscle cramping from lack of conditioning. But, it is always on the left side which is concerning. This has happened repeatedly over the past 4-5 years. At my annual physical last year, I mentioned this to the doctor and he says, “Yes, you are healthy, but lets run the test”.

As for the cardiologist, I think he is conservative and doesn’t know how to treat healthy people. I am not the typical patient he sees.

I do believe I am healthy and plan to continue my activities until I am old! But, I like to read and research this issue to make informed decisions. Thanks for your response.


#7

Interesting. I have found 220-age to work well for me when I am at peak cardio condition. I achieve peak conditioning after about 1 month of doing my 24 minute HIIT routine.

Your formula appears to work well when I am not in peak cardio condition. Right now, I am not at peak and I am achieving Max HR in the 174-175 range.