Another great monthly article by local physical therapist, John Fiore of Sapphire PT. Read ahead if you fall into any of these categories: You’re over the age of 40, you’re a runner or an endurance athlete, you lack in getting the proper amount of rest, or all three. As an ultra runner over the age of 40, John has some great insight on this issue and writes an article about long distance running and the effect on heart health.
Running is associated with health, vitality, youthfulness, and mental well-being. Aerobic exercise in general and running specifically have been shown to lower body weight, decrease diabetes risk, improve circulation, increase bone density, and lower blood pressure and resting heart rate. Do the health benefits of aerobic exercise imply more is better? An increasing number of studies and an excellent article in the August issue of Velo News magazine (http://velonews.competitor.com/cycling-extremes) point towards exercise moderation as the key to long-term cardiac health. As a distance runner and cyclist since age 16, reviewing the literature on the subject caught my attention and the goal of this article is one of awareness. While most of the studies included small sample sizes of predominantly male subjects and/or anecdotal evidence, the implications of long-term, high-intensity aerobic exercise cannot be ignored.
I highly recommend reading the Velo News article (see link above) for a detailed explanation and first-hand accounts of endurance athletes describing how their lives changed with the onset of atrial fibrillation. While we notice external manifestations of long distance running and endurance sports in the form of lean body mass, muscular legs, and the ability to run with ease, internal changes occur as well. The demand place on a healthy heart strengthens the heart muscle. At rest, our heard pumps 5 quarts of blood per minute. Running increases cardiac output to 25-30 quarts per minute. The heart is a muscle composed of unique muscle fibers. Similar to our leg musculature, the heart muscle beats more efficiently with aerobic training. The long-term hidden effect of high-intensity aerobic exercise is a thicker heart muscle. Cardiac arrhythmias (the heart flutters fast and inefficiently) have been noted in increasing frequency in aging aerobic athletes in their 40s and 50s. While additional cardiac risk factors such as genetics and lifestyle should be considered, the frequency in dedicated, competitive Masters (over 40 years of age) athletes is sobering.
Cardiac muscle fibers, like the skeletal muscle fibers of our extremities, require rest and recovery. Most dedicated endurance athletes, however, do not adequately rest or recover. Our busy lifestyles, the drive to push our training and racing goals, and our tendency to skimp on sleep and recovery further stress our heart. Cardiac muscle may subsequently develop myocardial fibrosis, or thickening of the heart muscle fibers, resulting in an inefficient heart. Coupled with arrhythmia or irregular/inefficient heart rate/flutter, and the picture is plain frightening.
As an ultra-runner who fits the profile of an at risk athlete, denial is not an option. A yearly physical is a great first step. Discuss your training, racing, nutrition, stress level, fitness goals, sleep pattern, and with your physician. Cardiac testing seems like a logical and potentially life-saving proactive step for any endurance athlete over 40 years of age. We all hope to enjoy the health benefits of running well into our retirement years. I can be reached for discussion or comment at the email address below. Thanks for reading!
John Fiore, PT
john@sapphirept.com
Sapphire Physical Therapy
Missoula, MT
References:
Case C, Cycling to Extremes. VeloNews.com. August 2015
Karjalainen J, Kujala UM, Kaprio J, Sarna S, Viitasalo M. Lone atrial fibrillation in vigorously exercising middle aged men: case-control study. BMJ (1998) 316:1784-5
Mont L, Sambola A, Brugada J, Vacca M, Marrugat J, Elosua R, et al. Long-lasting sport practice and lone atrial fibrillation. Eur Heart J (2002) 23:477-82.
Mont L, Tamborero D, Elosua R, Molina I, Coll-Vinent B, Sitges M, et al. Physical activity, height, and left atrial size are independent risk factors for lone atrial fibrillation in middle-aged healthy individuals. Europace (2008) 10:15-20.
Baldesberger S, Bauersfeld U, Candinas R, Seifert B, Zuber M, Ritter M, et al. Sinus node disease and arrhythmias in the long-term follow-up of former professional cyclists. Eur Heart J (2008) 29:71-8.
