Running may be harmful to your heart (Read 960 times)

http://health.yahoo.net/experts/dayinhealth/running-may-be-harmful-your-heart

The article mentions that Micah True died while running a marathon, which is not accurate. But other than that, the article is food for thought. Would be interesting to know what someone like Dr. Tim Noakes (author of "Lore of Running") thinks about the study. 

MTA: I actually read part of the actual study: http://www.mayoclinicproceedings.org/article/S0025-6196(12)00473-9/abstract

Here's the actual abstract:

"A routine of regular exercise is highly effective for prevention and treatment of many common chronic diseases and improves cardiovascular (CV) health and longevity. However, long-term excessive endurance exercise may induce pathologic structural remodeling of the heart and large arteries. Emerging data suggest that chronic training for and competing in extreme endurance events such as marathons, ultramarathons, ironman distance triathlons, and very long distance bicycle races, can cause transient acute volume overload of the atria and right ventricle, with transient reductions in right ventricular ejection fraction and elevations of cardiac biomarkers, all of which return to normal within 1 week. Over months to years of repetitive injury, this process, in some individuals, may lead to patchy myocardial fibrosis, particularly in the atria, interventricular septum, and right ventricle, creating a substrate for atrial and ventricular arrhythmias. Additionally, long-term excessive sustained exercise may be associated with coronary artery calcification, diastolic dysfunction, and large-artery wall stiffening. 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. Notwithstanding, the hypothesis that long-term excessive endurance exercise may induce adverse CV remodeling warrants further investigation to identify at-risk individuals and formulate physical fitness regimens for conferring optimal CV health and longevity."

The study itself is not a sensationalist as the article quoting it.

Overall, regular runners live longer.  Period.  Any multiple studies have shown that increasing levels of activity is beneficial.  Those are facts.  As the paper itself says, it is only a hypothesis that changes to the heart induced by running are harmful.

If running really harms the heart significantly (hypothesis), how does running prolong life (fact)?

These are population-level findings...average results.  This does not mean that there are certain individuals whose lives will be shortened by running.  But those anecdotal deaths do not negate the likelihood that you will benefit, not be harmed, from running.

IMHO these "studies" and hyped-up headlines against running happen so overweight reporters and other sloths can feel better about staying on the couch.

 

Which you? Which world? I prefer to be a person who dies on the race course, and not a slow death that goes on and on, rotting away. If they cut me open and see an enlarged heart,  may they eat it like Kevin Costner did the heart of the stampeding buffalo after the hunt in Dances With Wolves, and receive with an illuminating and transformational force my bravery, endurance and strength.

Nice. 

And speaking of 90's actors, the Robert Patrick character on "Last Resort" (that submarine show on ABC, which isn't half bad), had a pretty cool line a few weeks ago, as their sub is being hunted and there's a torpedo lock on them..."At least we'll die wet." 

Not sure what that has to do with anything, just sounded cool and made me think of this.

If running really harms the heart significantly (hypothesis), how does running prolong life (fact)? 

The abstract states "A routine of regular exercise is highly effective for prevention and treatment of many common chronic diseases and improves cardiovascular (CV) health and longevity." which is covers the second part of your question. The abstract continues to state  "However, long-term excessive endurance exercise may induce pathologic structural remodeling of the heart and large arteries." which addresses the first part of your question.

I think the study is saying that once you go past a certain threshold of running, you've maxed out the benefits of health and longevity, and if you exceed it, you may harm your heart. But that seems to apply only to certain individuals, not all.

The abstract states "A routine of regular exercise is highly effective for prevention and treatment of many common chronic diseases and improves cardiovascular (CV) health and longevity." which is covers the second part of your question. The abstract continues to state  "However, long-term excessive endurance exercise may induce pathologic structural remodeling of the heart and large arteries." which addresses the first part of your question.

 

I think the study is saying that once you go past a certain threshold of running, you've maxed out the benefits of health and longevity, and if you exceed it, you may harm your heart. But that seems to apply only to certain individuals, not all.

May may may.  That's the problem, there is not real evidence but that is not the way it is spun when the media gets ahold of it.

I would not be surprised at all if, past some certain level, you are doing it for some other reason than health.  Even without evidence I will buy that.  However I've read several studies on that, and all have either showed continued diminishing returns with a flattening of the benefit, or a maxing out of the benefit.  None...not one, that I have seen...has showed actual harm by progressing some amount past whatever threshhold max benefit is reached at.

One of the major problems with the studies that just focus on the cardiac changes is context.  They look at specific blood chemistry or structural changes and say "hey, this is similar to what we see with Condition X so it must be bad."  But a runner doesn't have Condition X, and often what is causing the change is not pathological.  The context in which the change in the body is being observed makes all the difference.

Take, for example, troponin levels.  That is a protein found in the blood after a heart attack.  Heart muscle releases troponin when it is damaged and dying from a heart attack.  So when they found it in marathoners they threw up flags about cardiac damage.  Well it turns out skeletal muscle releases it also when it is damaged/torn...like, from working hard running 26.2 miles and can't walk down stairs for a week.  Or take a low resting heart rate or enlarged heart aka "athlete's heart"....both are pathological in certain contexts, but perfectly normal and healthy in conditioned endurance athletes.

This is why I focus on the outcomes (ie longevity) data and don't place a lot of stock in these cardiac-only studies.

I am always suspicious of articles that toss out threshold numbers such as >32K a week or >15 mpw  or 60 minutes and especially the one inWSJ last week that said "running faster than 8 mph"

 How do you set an across the board danger threshold for pace?. There is no way I am going to believe that there is stress on spaniel's heart at 8 mph (7:30 pace) .   That's a recovery run for him.  OTOH I probably would keel over if I did a 8 mph run.   Well first I would bounce off the back wall after being flung off the treadmill, but if I did manage to stay on the treadmill, sure I can buy it might not be the best idea all the time and might produce significant stress hormones, etc. 

MTA: besides.  Living your life trying to avoid death by NOT doing things you love is kind of a boring way to go through life.  My father did that and spent 30 years dying. 

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 well said

> 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