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An “Iron” response…

The most famous medical blogger once direct-messaged me this advice:

“One thing I have learned from blogging is to never engage criticism.”

I’m going to break this advice.

The robustness of the response over the Ironman piece shocked me. As a bike racer, a cardiologist, and a happily married man, I have grown thick skin. Being called an atrocity really didn’t hurt me. What did strike me as reasonable criticism, however, was the lack of references. This I can remedy.

But first let me make three introductory points.

–Blog versus a scientific article: Let’s make sure that one understands the distinction between a blog post and a scientifically-vetted scholarly article. See disclaimer #3 in my “about the blog” tab:

Please do not confuse a blog post with a scientific paper or multi-referenced review article. I don’t have an army of foundation-supported researchers. It’s just me trying to help.

My words come free; that fact should speak volumes. In the blog-o-sphere, you, the reader, are the person doing the vetting.

–I am not a journalist–though perhaps a star-struck wanna-be.

–As a heart rhythm specialist, I see an atypical cardiac population. While my “plumbing” colleagues see America, as you see it in the mall, the state fair or sadly now, in our schools, I see you over-achievers: engineers, CEOs, doctors, lawyers, and of course, the endurance athletes. You sit on my table wide-eyed, staring forward in disbelief that a heart rhythm problem could occur in your sculpted bodies and minds. You have done everything right: gone to bed on time (mostly), ate good food, studied for tests and followed the training plan. How could you have atrial fibrillation?

This paradoxical observation: that certain arrhythmias–AF in particular– strike at the over-achieving, is something that interests me enough to write about. Perhaps, it’s because I am like you. I want to be the best heart rhythm specialist possible; I want to defy my genes and pedal more watts, for longer; I want to learn as many words as a WSJ writer; or come up with a fictional story that someone would find interesting. So I get your focus and drive.

But…I have also trained at the Academy. The distinguished center known for teaching this central tenet: as outlined in the comments by its director, RDB:

“In the pursuit of better, people often screw up good.”

Enough with the speech and disclaimers; here’s some real data:

Here is the seminal article on cardiac fatigue during the Ironman.

It was an ultrasound study of Hawaii Ironman finishers. The news is not good: measures of heart function looked terrible after the race. Though these changes reversed in recovery; this blogger’s opinion holds that things that damage your heart are not good. “Are you feeling lucky?”

On the association of atrial fibrillation and endurance exercise:

There are hundreds of citations documenting the risk of atrial fibrillation in long-term endurance athletes. You can start by feasting on these nuggets…

  • Karjalainen J, Kujala UM, Kaprio J, Sarna S, Viitasalo M. Lone atrial fibrillation in vigorously exercising middle aged men: case-control study. BMJ. 1998; 316: 1784–1785.
  • Furlanello F, Bertoldi A, Dallago M, Galassi A, Fernando F, Biffi A, Mazzone P, Pappone C, Chierchia S. Atrial fibrillation in elite athletes. J Cardiovasc Electrophysiol. 1998; 9: S63–S68.
  • Mont L, Sambola A, Brugada J, Vacca M, Marrugat J, Elosua R, Pare C, Azqueta M, Sanz G. Long-lasting sport practice and lone atrial fibrillation. Eur Heart J. 2002; 23: 477–482.
  • Hoogsteen J, Schep G, Van Hemel NM, Van Der Wall EE. Paroxysmal atrial fibrillation in male endurance athletes: a 9-year follow up. Europace. 2004; 6: 222–228.
  • Heidbuchel H, Anne W, Willems R, Adriaenssens B, Van de Werf F, Ector H. Endurance sports is a risk factor for atrial fibrillation after ablation for atrial flutter. Int J Cardiol. 2006; 107: 67–72.
  • Elosua R, Arquer A, Mont L, Sambola A, Molina L, Garcia-Moran E, Brugada J, Marrugat J. Sport practice and the risk of lone atrial fibrillation: a case-control study. Int J Cardiol. 2006; 108: 332–337.

Though the exact mechanisms, individual susceptibility and best treatment course for athletes with AF are not completely understood, it is completely un-credible to deny the association of AF and long-term exercise.

Coronary Calcium and long-distance running.

Here, the data are emerging. I offer you this piece from last year.

Cardiac Fibrosis and endurance exercise:

Here, I refer you first to Gretchen Reynolds, the famous NYTimes exercise writer. Her column is where I first learned the story of the marathon rat. I know, humans aren’t rodents, but the data from the highly respected lab of Stanley Nattel (Canada) are sobering. Yes, you can guess the results: rats that were run excessively (if given the chance, most rats will indeed run too much) developed areas of scarring in the heart.

And this very troubling finding doesn’t just happen in rats. Here are two studies that suggest the possibility of this irreversible phenomenon happening in humans: (there’s many more)

  • Whyte G, Sheppard M, George K, et al. Post-mortem evidence of idiopathic left ventricular hypertrophy and idiopathic interstitial myocardial fibrosis: is exercise the cause? Br J Sports Med 2008;42:304-305.
  • Cocker MS, Strohn O, Smith DJ, et al. Increased incidence of myocardial fibrosis with reduced cardiac function in elite high-endurance athletes: a cardiovascular magnetic resonance (CMR) study (abstr) Circulation 2008;118S840–b.

In conclusion…

There is ample data to generate the hypothesis that exercise has an upper-limit. My humble opinion, honed through a 15-year heart-rhythm experience, and a keen eye for the obvious suggests to me that long-term, low-intensity, ultra-endurance exercise (slogging, not racing) isn’t heart-healthy.

As sir Charles says, “I may be wrong…but I doubt it.”


P.S. Although this sounds a tad like self-promotion, readers can read my (archived) thoughts on exercise, inflammation and healthy living by clicking the categories tab on the right column of the blog. You will find many referenced articles in these posts.

11 replies on “An “Iron” response…”

I was an Ironman distance athlete for over 20 years. I completed 28 ironman distance races and was fairly good at it. I was diagnosed with Prinz Metal Angina about 5 years ago which has stopped my competing. My cardiologist seems to feel that this might of been brought on by doing such a long distance sport for so many years. What would be your opinion on this ? Do you know of any new research on this subject ?

Well written response but I’m sorry you had to write it. My comment to the original blog post was intended to try and change the tenor of what I saw developing in the responses. Pace lines, leaving the boys who are 20 years my junior in the dust, and cheating the wind is fun….don’t get me wrong; but sometimes it really is just a bike ride and we don’t have to become pace line nazi’s about it.
ps…I’ve also discovered by backing off a bit, the afib is not as much an issue.

@ Barbara – It seems to me I had read an article within the past year or so that addresses what you are experiencing with your heart. The term de-conditioning, I believe is the term they used. Also during my Affib experience it always seemed that the fitter I was the fewer episodes I had. ANd the on and off intensity of racing almost always set me off. I also believe that focusing on the issue had a direct effect on my attacks as well. Once I quit using a HRM my episodes became less frequent for a time.

You forgot to reference Rush Limbaugh who in his infinite prolixity noted persuasively that the increased costs of health care is a result of people exercising and sustaining all manner of injuries.

This is not to say of course that you are not an ‘atrocity’ or that ad hominen is not always the best counterpoint.

Now when does that psycho cross stuff start.


hmmm….. when do we get to the details of “xarelto” let the heros knock themselves out. maybe they’ve got a death wish. i want every bit of info. re afib and really don’t care about iron man, superman etc. .

Thanks for this piece. It could not be more timely for me. I was dehydrated during ImLou this year and ended up getting admitted to the hospital. It was my 2nd IM, I completed both and actually performed better this year in less heat than last year. I feel that I definitely worked harder this year in the run, improving by over 15 min. At the hospital they did blood tests and my cardiac enzymes were at “heart attack” levels.FYI I am 5’6″ and weigh 126 with no known underlying medical issues. I will be 40 this year. While. I recovered completely overnight with lowered enzyme levels I am left feeling that that was not good for my heart. My desire to compete at this distance has almost instantly vanished. Believe me I would not have pictured this reaction ever. Ahh mortality.. The doc attributed many of my symptoms to plain exhaustion but was concerned about the high enzymes. I will follow up at home, but wonder if you might have thoughts.

When you consider that those who compete in Ironman competitions are arguably the most dedicated, fierce and strong men and women in the world, it’s not too shocking that your initial post came under fire.

Maybe my comment (the first one) stoked it? haha.

Great rebuttal. Too much of a good thing, is well, too much.

I always preferred to say it “perfect is the enemy of good”, but I appreciate the response. And I’m sure no Ironman athlete will take your advice – after all they are Ironman – but what if someone did give up endurance activity. As you said, the state fair and the mall – great euphemisms btw – end up with a plumber and not an electrician. But I’m not sure having a plumber is any better than having electrician.

As for me, I remember a few years ago a good friend’s girlfriend said to me, “why would anyone want to do an Ironman.” The tone was snarky, and although I have thick skin too, I thought how ignorant this spoon-fed princess was. I didn’t bother explaining it and I surely can’t do it here – you see you can’t begin to understand until you have actually crossed the line. Then it all becomes clear. In the meantime enjoy the cycling, and I look forward to HRS some year where we sit down and you tell me all about your first Ironman. Hope to see you out there. Cheers, Thomas

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