Endurance training, is it harmful?

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I posted this response in the Lounge, but I thought that it deserved to be a post in this forum.

Here is a link to a podcast that may be of interest to some.

http://jaimeladulaneymd.podbean.com/e/j ... pisode-16/

Thank you so much for your post. Jami has a total of 17 podcasts with many interesting plant based people. Besides being a cardiologist, Jami is an endurance athlete. I emailed a question to him about this article and he promptly responded with an interesting reply.

http://www.wsj.com/articles/SB100014241 ... %3Darticle
https://www.youtube.com/watch?v=Y6U728AZnV0

If the article interest you, here is Jami's reply:

Thanks for the question. I have read those articles. I also trained under Dr. Thompson way back when at the University of Pittsburgh before he moved on to Hartford. I think one thing that is terribly missing from the studies is dietary information. If you have been to any races you will see tables of fat and sugar laden donuts and cookies and pizza. Most athletes feel they can eat anything they want because they exercise. Albert Salazaar the NY City Marathon winner and olympian had a heart attack at track practice at Stanford. While he was in great running shape he ignored his blood pressure and cholesterol. I agree with Dr. Thompson that the studies are not conclusive. Atrial fibrillation is the most common arrhythmias in adults over 50. I do not believe that athletes get more than the general population. There is evidence of micro damage in the heart muscle after a race not unlike the micro damage in the legs. They heal and perhaps make the heart stronger? I think pushing everyday to the max is not a good idea for anyone. My next podcast features Matt Fitzgerald who wrote 80:20 running. In a nut shell there is a lot of data that running most runs slow and 20% in zone 3,4 or 5 results in better race performance.
Eating a whole food no added oil plant based diet markedly decreases the inflammation in the blood vessels making a cardiac event much less likely. I have not had an athlete ever in my office with atrial fibrillation. I see atrial fibrillation many times a day in patients that eat the standard American diet on blood pressure medication and that are overweight with sleep apnea. It seems that not many Cardiologist are worried about what those people eat.
I intend to run marathons and do triathlons until my 90s if possible. I hope to be on the start line of Kona someday. I hope this helps. Send more questions if you like. Tune into the Matt Fitzgerald episode next week.
Thanks
Jami Dulaney MD

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I found this at Runners' World.

The (Supposed Dangers of Running Too Much

The (Supposed) Dangers of Running Too Much
What the data says, and what it doesn't.

My goodness, is it February already? It's been several months since the last round of articles warning that running too much will kill you–must be time for another one. What's that? No new data to publish? That's no problem, we'll just republish the same data. The media never bothers to check these things, and always reports it as if it were brand new.

The new article is published in the Journal of the American College of Cardiology, analyzing data from the Copenhagen City Heart Study. (And here, on cue, is one of the requisite newspaper articles: "Fast running is as deadly as sitting on the couch, scientists find.") The exact same data was published back in 2012 in the American Journal of Epidemiology. This time the authors are the same, but with the addition of James O'Keefe, who has been an author on pretty much every single one of the "running will kill you" studies.

As far as I can tell, the only new thing in the study (aside from the fact that a few more people have died) is that in addition to looking at hours of jogging per week, number of jogging days per week, and self-reported pace, they added a fourth category that combines the other three for an overall rating of "light," "moderate," or "vigorous" jogger.

Here is a piece by the same author published last year. Will Running Too Much Kill You?

That brings us to the third, and best, piece of evidence for the dangers of too much running, which comes from the Copenhagen City Heart Study. This is a well-run study that started in 1976 and now includes more than 17,000 subjects; you can read the full text of their analysis of the effects of jogging here. The first thing you'll notice if you read the abstract is that it doesn't say anything about "too much running" – in fact, its main conclusion is "The age-adjusted increase in survival with jogging was 6.2 years in men and 5.6 years in women. This long-term study of joggers showed that jogging was associated with significantly lower all-cause mortality and a substantial increase in survival for both men and women."

However, if you dig a little deeper, you'll find a small sub-analysis where they looked at the effects of how long and how fast the subjects ran. And sure enough, they found a U-shaped relationship, in which the best outcomes accrued to those who ran less than 2.5 hours a week at a slow pace. But there's a catch: only about 10% of the subjects were joggers, and they didn't start asking questions about quantity and pace of running until the later years of the study. Why does this matter? Well, take a look at the numbers for mortality versus jogging pace: in the group that reported their subjective jogging pace as "slow," there were 3 deaths out of 178 people; in the "medium" group, there were 12 deaths out of 704; in the "fast" group, there were 5 deaths out of 201. These are very small numbers. It may turn out that the effect was real – but if one slow jogger had been hit by a bus sometime in the last few decades, the mortality rate for that group would have jumped by 33% and we'd be talking about the "dangers" of slow jogging!