Running is often viewed as a way of protecting against cardiovascular disease, but it turns out runners might be at a higher risk for heart problemsthan previously thoughtRunning: The Risk of Coronary Events: Prevalence and Prognostic Relevance of Coronary Atherosclerosis in Marathon Runners. Möhlenkamp, S, Lehmann, N, Breuckmann, F, et al. Clinic of Cardiology, West-German Heart Center Essen, Essen, Germany. European Heart Journal. 2008 Aug; 29(15):1903-10. Epub 2008 Apr 21.. In one study, researchers used an imaging tool to look at the hearts of healthy endurance athletes that had taken part in multiple marathons and ultra-marathons (definitely not just weekend warriors)Diverse patterns of myocardial fibrosis in lifelong, veteran endurance athletes. Wilson, M, O’Hanlon, R, Prasad, S, et al. ASPETAR, Qatar Orthopaedic and Sports Medicine Hospital, Doha, Qatar. Journal of Applied Physiology, 2011 Jun; 110(6):1622-6. Epub 2011 Feb 17.. The results were surprising, to say the least. When compared to their non-runner counterparts, the aerobic gurus showed a high prevalence of heart stiffeningDiverse patterns of myocardial fibrosis in lifelong, veteran endurance athletes. Wilson, M, O’Hanlon, R, Prasad, S, et al. ASPETAR, Qatar Orthopaedic and Sports Medicine Hospital, Doha, Qatar. Journal of Applied Physiology, 2011 Jun; 110(6):1622-6. Epub 2011 Feb 17.. The problem with that: A stiffer heart is less efficient at pumping blood around the body — not the reward expected after logging countless miles on the roads.
The good news: In the majority of cases,the heart’s efficiency returned to normal within a week of crossing the finish line without any consequences. With repeated bouts of long distance training, however, research indicates the changes may be more permanentCardiac arrest during long-distance running races. Kim JH, Malhotra R, Chiampas G, etc. Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA. New England Journal of Medicine. 2012 Jan 12;366(2):130-40..
Going the Distance — The Answer/Debate
But exactly how much endurance training is too much? The majority of studies pinpoint 10 years as the time frame over which adverse effects can occur, but those years have to be filled with training sessions that would make even Lance stop and stare. Also keep in mind the athletes exhibiting stiffening were participating in at least 10 hours of intense endurance training per week and competed in competed in extreme events like ultra-triathlons (a 3.8 km swim, 180 km cycle, THEN a full marathon). That’s a far cry from the typical weekend 5K!
This article has been read and approved by Greatist Experts Dr. John Mandrola and Linda LaRue. Here’s a little more on what they had to say:
John Mandrola: “The overwhelming majority [of Americans] exercise far too little. In fact, I believe the U.S. suffers from severe exercise-deficiency. That said, however, accumulating data suggest the possibility of an upper limit of what the human heart can sustain. Each study on extreme exercise has its limitations. They enroll small numbers of subjects and are almost always non-randomized. And, studying exercise is tough because of the many confounding variables: genetic make-up of individuals, the presence of underlying diseases, and self-reporting of exercise amounts are just a few of many examples.
“But when taken together en bloc… it looks like optimal health is born and nurtured through balance. And there’s little about running (many) marathons or slogging through Ironmans that could be called balanced. Fun maybe, for some. Balanced? Heart-healthy? No way.”
Linda LaRue: “It’s important to take small studies or those not from top tiered research journals with a grain of salt. That said, most of the general exercising population are not ultra-marathoners. If you do happen to be that .001 percent, consult your physician if you have concerns. He or she can set up a treadmill stress thalium to properly evaluate your heart’s pumping ability.”
Distance running can bring a whole lot of health benefits — just remember not to overdo it. Over-exercise does not a healthy heart make!
Now we want to hear from you: How you do know when your body has had too much? Tell us in the comments section below!