Monday, July 2, 2012

I'm Worried About My Heart

Let's call June 30 the halfway point of the year (and it also happens to be my half-birthday, something I remember mattering when I was 3 and 4 years old and a half year was a huge portion of my life).

This half year, I have logged 2050 miles.  That's a lot of miles.  A lot more than half of my total from last year (3162 miles).  Maybe this is because I haven't tapered--and then recovered--from a marathon yet this year, which can make for 2 very low-mileage months.  

2050 miles.  I should note that somewhere around 100 of those miles were "hiked".  If I did the math right, that is an average of 11.3 miles every day.  That is an average of 80-90 minutes of running/hiking a day. 

Let this be my bi-annual super congratulations to myself for all these wondrous miles and number crunching!!!

Actually! Quite the contrary.  I'm sharing this as a good starting point to explore a new and potentially very scary and serious medical finding that makes my high mileage the opposite of congratulatory: distance running may be fucking up my heart and could ultimately lead to me dying at a younger age than someone who runs less.  So not cool.

I've never run with the motive of extending my life.  Sure, running has cardiovascular benefits and is generally believed to be healthy, but I've never thought, "the more I run, the longer I will live!"  Therefore, these recent studies aren't exactly spinning my world on its head.  

But it is really worrisome and frightening to read that my #1 hobby may be detrimental to my longevity.

Well let's dive into the study. It's about to get medical in here.  

The  Mayo Clinic recently released an article about the negative health consequences of endurance training.  Several weeks ago my dad (the anti-runner) sent me an early abstract of the study.  Then, more recently, a friend who practices medicine and is also a running enthusiast shared the article with me, as well as his early thoughts on the subject.

Pulling the language of his email and some of the study excerpts, the findings were as follows:

A 15-year observational study of 52,000 adults found that runners had a 19% lower risk of all-cause mortality compared with non-runners.  (So far, so good!).  Running distances of about 1 to 20 miles per week, speeds of 6 to 7 miles per hour, and frequencies of 2 to 5 days per week were associated with lower all-cause mortality, whereas higher mileage, faster paces, and more frequent runs were not associated with better survival.  (In short: for optimal survival, run slowish, not too far, not every day).

Studies also analyzed the effects of long-term long distance running via MRI results of 102 ostensibly healthy male runners from ages 50 to 72 who had completed at least 5 marathons during the previous 3 years.  These results were compared with 102 age-matched controls. 

The comparison found that about 12% of the marathon runners had evidence of "patchy myocardial scarring"--which was 3-fold more common than in the control group.  (I think this means running more than one hour regularly can lead to "something not good for your heart").

In conclusion, in some individuals, long-term excessive endurance training may cause adverse structural and electrical cardiac remodeling, including "fibrosis and stiffening of the atria, right ventricle, and large arteries." Cardiovascular benefits of vigorous aerobic endurance training appear to accrue in a dose-dependent fashion up to about 1 hour daily, beyond which further exertion produces diminishing returns and may even cause adverse cardiovascular effects in some individuals.

My Doctor Runner Friend noted that the studies raise some disturbing questions that are particularly worth considering for younger runners, who still have the chance to halt any potential damage. 

Read the details here and here, which is where the excerpts above were found.

There is a long list of questions to still be answered here (especially relating to how these findings relate to women, and how to identify signs that a runner may be at risk), so I don't think anyone needs to quit running longer than 60 minutes at a time.  I certainly don't plan on quitting long runs anytime soon.  I wouldn't even know where to begin.  But I am anxious to learn more.  In the world of running, the rules and facts seem to change by the year, so we can't jump off ship just yet.

Disclosure: I was paid a stipend by the anti-runners association to write this review.  I'm kidding.  This review is depressing!  Please share your thoughts, experiences, and your knowledge.


  1. As an official scientist (my business card says so!), I would take this study with a huge grain of salt. It's one of those articles that journalists and bloggers love because it's extremely controversial... especially since the publication coincided with the sudden death of Micah True (aka Caballo Blanco from Born to Run).

    I found these two sentences in the abstract to be very important:
    "However, this concept is still hypothetical and there is some inconsistency in the reported findings. Furthermore, lifelong vigorous exercisers generally have low mortality rates and excellent functional capacity."

    They also note earlier in the abstract that the cardiovascular scarring recovers 1 week after the endurance event. This is consistent with the recovery of the immune system after a marathon. No doubt about it -- endurance events are traumatic to the body, but as long as you let your body recover, I think you're good. I'm also pretty sure that NOT running/exercising is worse for you than running too much.

    1. Yeah. This.

      Also - Live life to the fullest, I say. And if that includes running (more than 30 minutes twice a week or whatever it was) then do it.

    2. So, what about someone like me who runs "an endurance event" almost every day of the week? i.e. no recovery period.

  2. Hey, I recently read coverage of this study on RW.

  3. I'm no expert, but I do have a heart thing, and a heart doctor who pays very close attention to what my heart does & what / how much activity I do & how intense. She has always encouraged me to run as much as I want, as hard as I want, and there is no reason to worry unless I start having serious symptoms, which I never have. Everything she's told me (and that I've read on my own) seems to lean very much in the pros-outweigh-the-cons direction, so I'm going with that til she tells me otherwise.

  4. I have a heart murmur and the doctor tells me that running is healthy and positive. Yes, I'm slightly more likely to die of a heart attack that the general population, but running makes my heart stronger and improves my overall health. Don't worry too much and just be happy that you can run.

  5. I have a heart murmur too, and honestly I would rather die young running and participating in longer distance training runs/races regularly than live a long, dull and boring life whereby my running was limited to a measly hour a day. I had a 'wobble' with running recently and bailed on a marathon because I was too scared that I was going to put in a terrible time, and I'm never forgiving myself for that. I've seen men in a local '100 marathon club' in their 50s, 60s, 70s and 80s (!) who have run 100 mile-ish weeks most of their lives. Some of them still put in marathons under 4 hours. If their hearts are not healthy, then who DOES have a healthy heart?

    I know that there are an increasing number of male runners having strange heart 'episodes' and collapsing/dying during races but these are generally found to be a result of pre-existing conditions exacerbated by running, not *caused* by running.

    Either way, although these results are interesting they don't cause me anxiety or distress, because as I mentioned above running long is what makes life worth living - without it, I'm not so bothered whether I get a heart attack or not. I think pegging out during a race would be the best way to go, rather than old and doddery with limited mobility anyway. At least I'd die happy on that basis!

    Perhaps this study is there to counteract the notion that one must run in order to be healthy? So many people do jump into running long in the name of 'health' and then end up disillusioned and injured...but what about mental health and quality of life? Those are immeasurable really by scientific standards but far more important than a few extra years with no purpose to them. Then again, I am biased because my life has rather limited purpose I suppose...


  6. Nooooo! That information depresses me. It took me years to be able to consistently run 90+ minutes a few times a week so to hear it's actually harming me is cruel. I expect we will be reading some counter studies soon since runners hate to hear anything dissing their sport and I'll hesitantly choose their side to believe while maintaining my freaked out on the inside state of mind. I guess on the days we don't feel like running long we can say it is for medical reasons.

    Way to go on your mileage. Your daily average is incredible!

  7. Ok, before you panic, I'd like to point out the following:
    Studies also analyzed the effects of long-term long distance running via MRI results of 102 ostensibly healthy male runners from ages 50 to 72 who had completed at least 5 marathons during the previous 3 years. These results were compared with 102 age-matched controls.

    Partially cheeky, partially serious - as much as men and women are the same, they also aren't. So it is difficult to know if this finding would extend to women. Also - we don't know why these guys started running in the first place - did they have some cardiovascular risk factors that made them think that they should run (or do a lot of exercise) in order to counterbalance their risk factors?

    That being said - it could be true - that's what the science seems to say. But it could also not be the case - which is also what the science seems to say. Overall though - the effects of worrying about it are probably worse for you.

  8. This is really interesting. I had actually read somewhere about very high mileage weeks (like 70+) can create heart murmors, so sadly I'm in the same boat as well. Kristens reply above it also interesting.

    I think there will be a lot more studies done on this because a lot of athletes practice for more then 90 minutes daily.

  9. Will read study in entirety then return and report back. Later.

  10. Oh good, another STUDY. Everything's gonna kill us! I say forget it and do what you enjoy. If the running doesn't get you, something else will.

    Just floss your teeth everyday, and that'll balance it out. Is that how teh sciencez works?

  11. I struggle with studies like this - If I worried about everything that could possibly kill me, i'd live in a bubble in my bedroom. Death is going to happen sometime.. Might as well enjoy the short amount of time that we have.

  12. that is so interesting - thanks for posting!! Even though it definitely piques my interest, I don't think I'll be scaling down the mileage any time soon. I agree in that it should be taken with a grain of salt for now, and more long-term studies are absolutely necessary before any hardcore recommendations happen. That could take years and years. And even if it does happen, I think I'd still do what I'm doing and enjoy it. The benefits (probably) would still outweigh the risks.

  13. Very interesting read, I've done a lot of poking around about this. I have genetic high blood pressure (controlled by meds), I had a scare last year where my heart rate zoomed about 30-40 bpm faster suddenly (later possibly attributed to medication change that week + a cold). It hasn't happened since but of course I turned Dr WebMd and found that I was going to die immediately (HA!). Anyways, I'd be curious if they had done this study with women as well since previous studies have shown men are more predisposed to this than women.

    An interesting blog I found is The Athlete's Heart, he's a cardiologist and endurance athlete.

    Some interesting info on there if anyone else is curious.

  14. This is very timely, seeing as how I had my first EKG today. I will also have my first cardio echo next week. (chest pain, but the doctor is 95% sure it's muscular - but thought she might have heard a murmur)

    Ah, this shit sucks. It took me 25 years to find running and I'd really like to keep doing it.

  15. Wow, that is insane how much you've run already this year - an average of 11 miles a day is amazing.

    About the study, those results don't surprise me. Doing a marathon for instance likely isn't the best for your heart because it probably stresses it out too much. I mean the pain that we feel near the finish line can't be good for us long term. But I'm not going to change, and if I end up dying early from it, so be it. I'd rather go out happy and running and to not go for what I want to do.

  16. I'd rather die doing something I love than "live" a little longer holding back. I've only recently started running but when I think about all the time I wasted playing video games and being a lazy person anytime other then when I was at work it makes me run harder. I don't ever want to be that person again.

  17. Ugh. Medical findings suck. They always scare the crap out of you, and then the next thing you know, someone else comes out with a different study that completely negates the one that was just freaking you out. It's so hard to know what advice to take seriously, and what to ignore. The way I look at it, all of our bodies are different and you just have to go by what feels good to you.

  18. I want to have more information, more studies on this... My first thought after reading this was 'I wonder if the runners that had hardening/heart problems had an underlying heart condition that was accelerated by the running' or maybe that's my denial speaking!!


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