HR blocked too low (for age)

Hello.

I recently started to apply for my VISA for Sufferlandia, and as it turns out, I am enjoying it already - did only Full Frontal for now.

Testing revealed what I already know, that I lack 1 minute MAP strength, and I believe that is because despite my theoretical HR limit of 172 (220-age) I never see numbers higher than 160-162 in my even most intense training.

Since I have a little more weight than a standard cyclist (around 98kg), I have a theory on that. Also, ergometry with ECG had to stop at about HR of 125 because my blood pressure went over 250.

My theory is that some failsafe inside me is preventing me to reach higher HR so I wonā€™t shoot my blood pressure into really dangerous levels.

So, if that might be the case, according to your experience, what to do? Lose weight (ah), train normally, and hope it will clear and, train cautiously?

Thanks

220- age is only a very crude guide to your max be. Thereā€™s a huge amount of individual variation. Weight and exercise history have an impact too.

Thereā€™s a better approximation (but itā€™s is still only that) here ā€œHeart Rate calculator - CERG - NTNUā€ https://www.ntnu.edu/cerg/hrmax

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Thanks for the link. According to them, my max HR would be 182! Do you have any thoughts on my other theories?

Hi,

Iā€™d say always consult a physician before engaging in Intense athletic efforts. On the second hand also what is your current fitness? Have you been training endurance sports for a long time? or have you been inactive for long periods? thereā€™s an adaptation period while your body gets used to the ā€œnewā€ situation. Also, there are people with natural low HR levels. E.g Chris Froome reportedly has a max HR of 165!!! can you imagine that?
As for your other question bringing your weight to a healthy range is always good!
Hope this helps you!

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Thanks JC, for your input. I consider myself fit, other than weight. For last 5 years, by average mileage is about 10k km yearly. And that is not leisurely pace, not fast, but sportive. And on all rides, when going hard, HR comes to about 152-155 and stays there. Just because of that, I started to think that maybe there is whole another ā€˜zoneā€™ above my max HR that is physiologically possible for me, but blocked currently for some reason.

I had hearth problems years ago, but it seems to be faded recently (I checked and re-checked everything).

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As you exercise the metabolites that your muscles produce have the effect of opening up the capillaries in your muscles. This has the effect of lowering your peripheral vascular resistance and (for the same Cardiac Output) lowering blood pressure. Your heart compensates by increasing the cardiac output by increasing the stroke volume and rate.

It might be that you, as a result of the type of training that youā€™ve done over the years, can only recruit a smallish proportion of your muscles and that this is the reason that your heart rate doesnā€™t rise any further. I understand that triathletes have different max heart rates for swimming, cycling and running because of this.

I canā€™t think of any physiological mechanism that would ā€œblockā€ your heart rate in the way you describe.

If my thinking is right, then altering the type of training that you are doing should stimulate more muscle and allow you to recruit them better, which should then make your heart work harder to maintain the cardiac output, but take it slow and gradual rather than risking overtraining would be best.

Thanks Matt. I am not a doctor, just an interested layman, I connected two data points:

  • my BP very high when measured during ergometry
  • my HR not going above a certain value

That is why I concluded that maybe there is a negative feedback mechanism preventing me from blowing up from BP too high :slight_smile:

I wouldnā€™t rely on the (out-dated) 220-age formula as any kind of meaningful benchmark. Itā€™s miles away for me, but Iā€™m at the other end of the spectrum. According to that formula I should have a max HR of 168, but In reality I can hit 189 when fresh. From what Iā€™ve read and observed there is a very wide spread of HR profiles. Some people are low revving diesels, while others are high revving petrols. But I donā€™t believe there is much you can do to change whatever ā€œengineā€ type you have and I donā€™t believe one type is necessarily better than another.

In your shoes I would be inclined to get a medical checkup to make sure there is no problem. But I donā€™t think your relatively low max HR is particularly unusual. Nor do I think you will be able to unlock any further zones above it. But that in no way means you canā€™t still improve your power throughout your range.

Thanks Peteski -

checkup done, all good except high BP when under load.

Cool, so I wouldnā€™t worry at all about not conforming to an old, outdated benchmark figure. At best this would represent an average value across the whole male population, but takes no account of your height, weight or any other physical parameter other than your age and sex! Out of interest what is your resting HR? If that is also very low then It would point toward you being a diesel type of guy. I have a friend who has a resting HR of around 45 and a max around 160. My resting HR is 60 and max 189. We are the same age, similar fitness history, but he is a good 15 kg heavier at same height.

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I am not sure about resting HR, but I frequently check my Garmin upon waking up, and usual LOW numbers are in range 44-48, depending on how fatigued I am. If it is on the low end of the spectrum, I know that I am well-rested, and if it goes toward 50-ish, then I need to take a break from the training. Yes, definitely a ā€˜diesel-poweredā€™ physiology.

You see thatā€™s a good 15 beats lower than my typical resting HR and well below the average low benchmark figure of around 60. Just shows how personal HR profiles really are. What Iā€™ve observed as Iā€™ve got fitter is a significantly lower resting HR (I was at around 70 before I started training regularly), but very little change in max HR, if anything a slight reduction at the very top end - maybe in line with getting older. In my mid-20s I had a max HR of around 200, now down to 189 in my early 50s

I am seeing a gradual reduction of both my max HR and my resting HR, as I age and my fitness improves.

Well - maybe I can conclude that I will give my best to train with my new toy (Sufferfest) and see what happens. If there is some real science behind those training sessions, something will move.

Seems the formula (220-age) never goes away.

Iā€™m a living example how wrong this formula is. My max has always been about 15-20 beats under the formula number. When I was 50 my max was about 150. Now when Iā€™m 66 I estimate my max is 140+ something, but I have not tested it. And donā€™t see any reason making a test.

As far as HR is concerned, the likely improvement you will see is a higher lactate threshold as you get fitter. Your max HR will most likely remain the same, but your threshold will get closer to your max. You may also see your resting HR come down further. Thatā€™s been my experience at least and ties in with things Iā€™ve read.

Not sure if it helps, but my training is around 65% Z3/Z4, so threshold, at 70 RPM. Over time, my HR has adapted to that, so itā€™s relatively low, if you take/trust/believe the relationship between power, cadence and HR.

I also have a low resting HR, as Iā€™ve been woken up in the middle of the night while in the hospital, as my HR drops to the low 30ā€™s when in deep sleep. My max HR is around 174, which I do only reach occasionally and Iā€™m 60 years old.

individual HR max can only be determined by (lab) testing, everything else is pretty vague

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I would have thought HR max is very easy to measure by yourself with a sufferfest. Iā€™m pretty sure I know my limit!

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I agree, but only under ideal circumstances. And even so, you may get a different result if done ā€˜in the same personal stateā€™ within a few days.

Plus, there are the outliers that most devices will occasionally show, and thereā€™s the accuracy issue.

Lab test is fine, but considering everything is ideal and calibrated near optimum, it will give you a result that youā€™re going to be working with at home. Probably/possibly with different devices, unless the lab allows you to come with all your own.

My max HR varies with fatigue of course, but itā€™s always consistently within a 5 beat window at the top end and when fresh I can nearly always hit the same peak. Iā€™ve used 3 different HRMs over the last couple of years and all shown the same max numbers. Only slight variation Iā€™ve seen is between indoor and outdoor max - I can hit a slightly higher peak outdoors (maybe 2 or 3 beats higher), probably due to air flow and better cooling. But in the context of this discussion the difference is negligible.