“When a Remedy Becomes a Poison” Peracelcus (1493-1541)
“Often the remedy is deemed the highest good because it helps so many.” So too with exercise and it’s the dose that tips the scales. Peracelcus was a German/Swiss physician, toxicologist and chemist. His famous quotes live on as a warning for those of us who love to run or bicycle fast and long.
A routine of regular exercise, as little as 15 minutes a day, results in health benefits that increase in-step with the dose. More minutes equal more benefits in preventing and even treating chronic diseases, improving the health, preserving the function of your heart and blood vessels, and extending life expectancy seven-years longer than that of people who do not exercise. However, these added minutes come with the warning that exercise beyond 50 to 60 minutes “does not yield further benefits”. For the more determined doubters, there is the potential that in some individuals who consistently exceed the time limit, the adverse effects may outweigh the benefits, especially when injury to the myocardium and metabolic derangements are accumulated across the years.[i] [ii] [iii]
Excessive Endurance Exercise
Recent studies have found a potential for heart damage when endurance exercise is excessive. The fact that the chambers of the heart are stretched to accommodate the increase in cardiac output is well established by echocardiography. New, but still controversial data, show that the heart’s muscle fibers can tear when stretched too much, just like other muscles and, especially, I would think, the thinner muscle wall of the right ventricle. Such tears result in fibrosis (thick, stiff scars), which reduces the effectiveness of the pump, both in relaxing and contracting, and creates a friendly milieu for life-altering arrhythmias, especially atrial fibrillation. There are also the alarming possibilities for stiffening of the large arteries as well as calcification of coronary arteries, the harbinger of heart attacks. While awaiting new data, marathons, Ironman competition and long-distance bicycle races should not be trained for nor participated in. Dr. O’Keefe says that if you must do a marathon, do one and then get on to something healthy.
From the perspective of this elderly one, long term results DO matter and life after 77 (my definition of “elderly”) can be healthy, active, still exercising and full of really sweet surprises. Any regrets? Well, sure and for me they’re linked to youthful inattention to elder-warnings. In defense of my daring youth, there was no science linked to the warnings and I couldn’t see the point. You, dear 21st century athletes, have plenty of science. The studies referenced here are respected and were not small. Some of the authors were dedicated excessive endurance runners or bikers and all are Cardiologists and/or specialists in Internal Medicine, who could sense the danger and had concerns for their own health and longevity as well as yours – pretty amazing. I’ve heard, “So what? When you’re 80, who cares?” Believe me, you will care!
Who’s at risk here? Everyone? We don’t know yet. Further investigation is necessary to find the threshold for toxic doses of intense exercise and identify individuals who are at risk, especially in the light of the fact that some men and women who are vigorous exercisers live long healthy lives. Meanwhile, remember that after 50 to 60 minutes of intense exercise we are whistling in the wind.
By Mary Boudreau Conover
Mary Boudreau Conover is the author of eight books, five of which she co-authored with Cardiologists in the U.S. and The Netherlands on the subjects of Electrocardiography, Arrhythmias, Laboratory Tests, Heart Sounds and Murmurs, and Cardiovascular Procedures. Across three decades she has educated thousands of Critical Care Nurses and a significant number of Physicians in the U.S. and Canada through her two-day workshops on “The ECG in Emergency Decision Making”. Having retired from the lecture circuit and regretfully from her seasons of skiing Mammoth Mt, she posts an occasional article, works out at CrossFit with her coach, Jim Baker, and is inspired by the encouragement of her family and friends.
Mary Baurdreau Conover has been a mentor of mine for nearly 10 years, but more importantly is a close friend to me and my family. Our “go to” gal is Mary because of her depth of knowledge in matters of science and life! Mary has been an editor and adviser for many heavy hitters in the Strength and Conditioning world and continues to do so today. She inspires me and the expression of Eva T. Strength and Conditioning. In closing, Mary is a shining beacon of light for all of us and leads a life that is “Strong, Healthy, and Happy!” -Eva T.
[i] Patil HR, O’Keefe JH, Lavie CJ, Magalski A, Vogel RA, McCkullough PA: Cardiovascular damage resulting from chronic excessive endurance exercise, Missouri med (2012) 190(4): 312-321.
5 push ups, 5 sit ups, 5 air squats, 10 rounds. ~GO!