femto 3 days ago

Related, the ambulance system where I live has been running a clinical trail using a mobile ECMO unit (Extracorporeal membrane oxygenation) [1,2]. An invasive procedure that oxygenates and pumps blood. It's boosted survival rate for those who are not responding to CPR (15-20 minutes duration) from 3% to 28%. The general CPR survival rate is an exponential looking curve: starting around 20%, reducing to 10% at 10 minutes and 3% at 20 minutes [3].

[1] https://www.abc.net.au/news/2025-04-07/nsw-ambulance-ecmo-tr...

[2] https://www.nsw.gov.au/media-releases/mobile-cardiac-treatme...

[3] https://www.bmj.com/content/384/bmj-2023-076019

Edit: The numbers in [3] are optimistic, as they are for in-hospital CPR, not out-of-hospital CPR.

proee 3 days ago

I don't know if this is true, but my cardiologist said that everyone who trains hard for a marathon has some level of heart damage from the excessive training. This sounds extreme to me, but I was in to see him for some AFIB episodes that were triggered from pushing myself too hard. It's worth noting that endurance athletes are 2 to 10 times more likely to develop AFIB compared to non-athletes. So this is a bit of warning to apply some level of moderation to your training.

  • runjake 3 days ago

    > my cardiologist said that everyone who trains hard for a marathon has some level of heart damage from the excessive training.

    This strikes me as either your cardiologist being wrong or you misinterpreting what they said.

    Can you damage your heart doing endurance events? Most certainly. I’ve seen at least two cardiac arrests during events where the person did not survive.

    Does everyone who does an event suffer heart damage? No.

    There have been quite a number of studies mentioned in ultramarathon journals that contradict your claim.

    Additionally, I have run so many marathons and ultramarathons I’ve lost count. I just recently had my own extensive (and expensive, despite insurance) cardiology work where they observed no such damage. I asked them whether endurance sports cause heart damage, because I’m old and thinking of starting up again and the summary of their answer was “as long as you’re training properly, you’re good”.

    That said, certainly these events put short term (~weeks/~months, depending) stress on the heart.

    The article mentions new medical technology and techniques as increasing survivability but I also wonder if better training and awareness is also a key. When I started running ultras particularly, it was just a bunch of nutcases. But now you have “hobbyists” like soccer moms running them (and I’m thrilled about that) and doing well at them because there are sets of extremely good training knowledge out there.

    • 9283409232 3 days ago

      > Does everyone who does an event suffer heart damage? No.

      This is not what they said. Your doctor said that “as long as you’re training properly, you’re good” but I've trained with a lot of other people and most people don't know what properly means. They just go hard.

      • runjake 2 days ago

        This is what they said and I quote:

        > my cardiologist said that everyone who trains hard for a marathon has some level of heart damage from the excessive training

        • 9283409232 2 days ago

          > everyone who trains hard for a marathon

          > Does everyone who does an event suffer heart damage?

          These do not mean the same thing. Everyone who trains hard for a marathon is not everyone who does a marathon.

          • runjake 2 days ago

            OK, I'll keep playing.

            There's no evidence I've seen that "everyone who trains hard for a marathon has some level of heart damage".

            Can you point me to such evidence?

            • 9283409232 2 days ago

              Whether or not it is true has nothing to do with my point. My only point is that what you claim the OP said is not what the OP said.

      • phs318u 3 days ago

        This. "training properly" is doing a LOT of heavy lifting here.

    • texuf 3 days ago

      When doctors say “everyone” they mean “the statistically average person”

      • milesrout 2 days ago

        No they do not. That makes absolutely no sense.

    • ekianjo 3 days ago

      > cardiology work where they observed no such damage

      How do you observe such damage without a biopsy?

      • rhyperior 3 days ago

        An EKG or EKG stress test, for example, will tell you a lot.

        • runjake 2 days ago

          The EKG stress test portion was fun.

          "We want you to run until you feel tired." (I forget their exact wording, but that's the spirit)

          "Uhm, we're going to be here for hours."

          "OK, get it up to 145bpm and then stop whenever you want."

          "I never get up to 145 bpm!"

          "We'll get you up to 145 bpm".

          And indeed they did. An aside: their treadmill goes steeper than mine at home does. :-P

    • jimbob45 3 days ago

      What’s your marathon PR though? (Fudge the numbers if you’re willing to share them or someone might be able to doxx you)

      • runjake 2 days ago

        My PR is ~3:40, but to do that, I dropped a lot of weight (~30 lbs) and did a lot of dedicated training with a, let's say, reputable marathon coach.

        3:40 is slow by "serious layperson" marathon standards, but it was about the max I could get with my at the time 40-ish yo body and ~6 months of serious training, starting from a solid baseline.

        I am slow, so my average marathon normally hovers around 4:00.

        I am not fast by any measure, but I do have ridiculous endurance.

  • altcognito 3 days ago

    Everything after about 60 minutes is overkill for health, and truth be told, probably 30 minutes of reasonably vigorous cardio is probably an ideal amount. I say this as a daily runner and someone who runs halves fairly regularly.

    https://archive.nytimes.com/well.blogs.nytimes.com/2012/01/1...

    • Mistletoe 3 days ago

      For people that want more data, I always go back to this study which I find fascinating. I run once per week and 7 miles at a time.

      https://www.mayoclinicproceedings.org/article/s0025-6196(16)...

      Something like that seems to have the best outcomes (will it help you not die?) and it fits with how I feel. Running more than once a week always made me get worn down. My best 5k time came from running one long run a week and lifting weights the rest of the week. I was effectively just wasting my time with the other runs in the week. I don't suggest this for a real professional runner, but for weekend warrior types like me, I think it works well. And I have won my age group before in a race, so I'm not a total novice.

      • mathieuh 3 days ago

        It depends what your goals are. Also, some people can handle more volume than others, and some people need less volume than others. I am training for a 340 km/3000 m elevation bike ride in June and I am doing 15 hours of cycling per week which is as far as I plan to take it.

        This is about 50 % beyond what I would normally be doing, and a couple of times after upping the volume I did get close to backing off because I felt like I was overdoing it, but after pushing through for a week I started recovering again.

        The difference in my fitness is almost unbelievable. I can knock out 160+ km rides with no problem when in previous years I would have found them very difficult.

        And beyond just results on the bike, I feel much better in myself, even than when I was doing 10 hours per week. I never get out of breath, hills I used to walk up with the dog I now realise I am walking up breathing through my nose the whole time, I handle heat much better, my resting heart rate is in the mid-to-high 40s, I have more energy, etc.

        If your goal is to do well at the local 5 km run in the park then lower volume is probably fine, but in my personal experience I still don’t think I’ve hit my limit even at 15 hours per week.

      • sampullman 3 days ago

        I've found the opposite, if I run 10-15k once a week I can just barely maintain my fitness. I only start to see improvement with 3+ runs a week (at least 20 miles total), and one of them needs to be pushing the pace.

        Maybe I'm reading it wrong, but the study seems to claim that running less than the recommended amount is still good, not that running more is necessarily bad:

        > ...these highest runners still had trends of lower mortality than did nonrunners and only a nonsignificant trend of higher mortality than did the lower-dose runners (P≥.05). Therefore, until we have more compelling evidence on running doses and mortality, we should emphasize that “even a little is great” rather than debating whether “more is better or worse” from a public health perspective.

      • komaromy 3 days ago

        What kind of 5k time did you hit with that training?

  • skylanh 3 days ago

    I find HN rife with its own form of "I'm too smart" bro-science.

    Your cardiologist spoke directly with you; they're a trained, accredited, licensed, and in good standing professional. Go with your interpretation of what they told you.

    Additionally, lets learn how to over-come HN's own form of bro-science because I'm pissed off right now.

    Step 1: go to pubmed and throw the most basic of terms in: "marathon training cardiology damage"

    Step 2: Quickly review the studies listed; we want to see studies after the advent of advanced hormone and mRNA quantification--that's around 2005 to 2010 or so--or anything within the last 5-10 years.

    Step 3: Read through one study especially if it appears to be well setup or specific to what we are trying to understand--we can look at the abstract if we have some knowledge in the area, or are just getting a feel for the topic.

    Step 3b: take note of terms; this study is an easy one and has everything we want to see in the abstract: https://pubmed.ncbi.nlm.nih.gov/36767963/ "Effects of Long-Term Endurance Exercise on Cardiac Morphology, Function, and Injury Indicators among Amateur Marathon Runners" in the Int J Environ Res Public Health . 2023 Jan 31;20(3):2600. doi: 10.3390/ijerph20032600.

    Step 3c terms:

    - cardiac morphology, function, injury indicators;

    - left ventricular end-diastolic volume and left ventricular end-systolic volume indicator;

    - myocardial injury indicators, serum levels of cardiac troponin I, creatine kinase (CK), creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), aspartate aminotransferase (AST), and N-terminal pro-b-type natriuretic peptide (NT-proBNP)

    - Long-term high-intensity endurance exercise (not indicated; but "High intensity Steady State" (HISS) and similar will creep into our vocabulary)

    Step 4: refine search to something like "cardiac morphology myocardial injury marathon amateur"; throw on "biological indicators", "creatine kinase"

    Step 5: rinse, repeat, and read deeper into some of the studies.

    Anyways, "Long-term high-intensity endurance exercise caused some damage to the hearts of amateur runners." and your cardiologist said the same. Or you can believe some rando giving medical advice on this forum. And honestly, I'm beyond irritated at the consistently bad takes on medicine, biomedicine, and exercise on YC HN.

    • milesrout 2 days ago

      >Anyways, "Long-term high-intensity endurance exercise caused some damage to the hearts of amateur runners." and your cardiologist said the same. Or you can believe some rando giving medical advice on this forum. And honestly, I'm beyond irritated at the consistently bad takes on medicine, biomedicine, and exercise on YC HN.

      No, his cardiologist apparently said this:

      >my cardiologist said that everyone who trains hard for a marathon has some level of heart damage from the excessive training.

      There is a huge difference between "some damage observed in some people that do X" and "everyone that does X has damage from doing X". They are completely different statements. They say different things.

      Scaremongering about the "dangers" of exercise causes much more harm than exercise does. Even if it were true, it would still be better to have a few heart attacks from exercise than TONS of heart attacks from obesity and unfitness.

  • asdfman123 3 days ago

    As someone who enjoys distance running and has run some half marathons before, endurance running has some negative side effects (not as negative as no exercise at all, though).

    Sprinting, though, 3x/wk, is very good for you.

  • lumost 3 days ago

    You can feel this in extreme cardio endurance activities. After a certain point you can quite literally feel pain in your chest while being earstwhile healthy.

    • js2 3 days ago

      I've run over two dozen marathons including Boston five times, several 50Ks and 100Ks, two 100 milers and both 12 and 24 hour events. I never felt pain in my chest.

      These long events leave me feeling weary and fatigued, and sore in places no doubt, but never what I'd call in pain, and definitely not in my chest. If I ever felt pain in my chest I'd definitely get that checked out.

      • lumost 3 days ago

        It was a high altitude mountaineering event where the only real choice was forward. 5 hours in the 160+ hr range was… unpleasant. This was also my first exposure to such durations of cardio activity.

    • forgotTheLast 3 days ago

      I would talk to my doctor about that if I was you.

EncomLab 3 days ago

I - like ~20% of the humans of planet earth - have a bridged LAD coronary artery. The vast majority of those who have this congenital deformity will never know it and remain asymptomatic; a small cohort of those will, like me, have a minor heart attack and fully recover - a smaller cohort will die of sudden cardiac arrest, many of them males in their teens while practicing football or performing similar cardiac stressing events. Unfortunately determining this congenital deformity requires invasive radiological imaging - hopefully this technology will assist in it's identification sooner.

dm03514 3 days ago

“The most common diagnosis associated with sudden cardiac arrest was coronary artery disease.”

I wonder the fitness levels of the people that experienced cardiac arrests. Like were these first time runners that signed up to run a marathon?

  • cj 3 days ago

    Short answer is "being in shape" (even for a marathon) doesn't guarantee you'll be free from heart disease.

    • milesrout 2 days ago

      Biology is complicated. Nothing GUARANTEES anything.

      Being in shape makes you far less likely to die or be injured by a heart attack than being a fat unhealthy pig. Anyone that refuses to accept this is living in denial.

      Health matters, exercise matters, and life has random elements but is not random. Choices do have consequences.

  • readthenotes1 3 days ago

    Distance running has, afaik, little to do with coronary artery disease (tho exercise can increase HDL some, it's only moderately protective and I recall that there are some studies that say that Marathon running actually is not healthful).

    In my understanding of what happens during sudden arrest is that after having filled the artery wall tubing with as much plaque as it could stand, instead of ruptering through the outer wall , it collapses inwards, cutting off blood supply to the heart muscle.

    • WalterBright 3 days ago

      > there are some studies that say that Marathon running actually is not healthful

      I read about marathon runners saying it takes a month to recover from a marathon. That can't be healthy.

      • js2 3 days ago

        I ran 16 marathons in 2016 as well as a 24-hour event where I completed 105 miles, then ran the Chicago marathon less than two weeks later.

        I never felt healthier in my life than that year.

        This is not medical advice, but the body is amazingly adaptable and can withstand some pretty high levels of stress if you build up to them slowly and are willing to back off when it tells you to.

        • anal_reactor 2 days ago

          I do two hours of moderate cycling every day and I feel like fuck.

      • AngryData 3 days ago

        Of course you gotta also consider how many under train for the marathon and essentially over commit themselves to the event when it does come along. But it definitely isn't healthy if they require more than a day or two of physical recovery after a physical event.

teleforce 3 days ago

Fun fact, there are two types of cardiovascular disease (CVDs), one being normal diseases and another is genetic.

Almost all of the deaths or mortality for young athletes (amateur or professional) are due to the genetic, for example mostly are based on the hypertrophic cardiomyopathy (HCM) [1].

Another fun fact, unlike normal CVDs, genetic based CVDs like HCM the death is totally preventable if it can be detected and treated early.

In many countries now CVDs screening including ECG is mandatory for professionsl atheletes, hopefully it can be made mandatory for amateur athelete as well e.g marathoners [2].

[1] Hypertrophic cardiomyopathy:

https://en.wikipedia.org/wiki/Hypertrophic_cardiomyopathy

[2] Periodical cardiovascular screening is mandatory for elite athletes:

https://pmc.ncbi.nlm.nih.gov/articles/PMC1896145/

  • Lucasoato 3 days ago

    Which tests could detect genetic based CVDs?

    • teleforce 3 days ago

      Currently for highest accuracy mostly using MRI especially for HCM [1].

      Personally I'm working towards accurate non-invasive screening of HCM based on ECG for professional athletes in initial collaboration with Oxford University and local national sport institute.

      [1] Radiopaedia: Hypertrophic cardiomyopathy:

      https://radiopaedia.org/articles/hypertrophic-cardiomyopathy

riversflow 3 days ago

Interesting, I’d speculate that better hydration/hydration education and science play a part. While it used to be thought of as “part of the sport” it seems to be accepted that dehydration is really bad for you with no upside at all and to be completely avoided.

jfengel 3 days ago

Yeah, it's been a while since anyone died during a marathon I was doing. Back when I started in the early 90s it would be one every couple of years or so.

elliotto 3 days ago

Can't read the actual study because it's behind a medical journal paywall. It looks like they speculate that improved CPR training and AED use has caused this.

My speculation would be that these mega running nerds all wear watches that track their heart rate 24/7 now. I suspect if something is wrong then you get an earlier detection rather than only discovering it on a race day.

whycome 3 days ago

When I see a headline like this I like to play a game. I try to guess an absurd correlation ("it's the fancy new shoes") and try to guess some sort of possible mode of action. ("Change in forces on legs causes a change in blood flow through the body")

killingtime74 3 days ago

My dad is a big marathon runner and he's specifically had heart function tests (The one on the treadmill with the mask) with his cardiologist to reduce this risk further.