Overexercising and the Risk for Atrial Fibrillation

In recent years, convincing evidence has come to light demonstrating that atrial fibrillation in many cases is a disorder of poor lifestyle choices, in particular, being overweight. (Emphasis on the phrase “in many cases.” Not in all cases. Clearly, lots of people with atrial fibrillation have exemplary lifestyles. In these people, there is some other cause for the arrhythmia, including things like thyroid disease, hypertension, or mitral regurgitation.)

In clinical studies, overweight patients with atrial fibrillation were able to greatly reduce their symptoms, and in many cases eliminate atrial fibrillation altogether, with an aggressive lifestyle modification program that emphasized weight loss. Further, losing weight was accompanied by significant changes in the structure and function of their hearts, which promoted normalizing their heart rhythms.

What About Exercise and Atrial Fibrillation?

Several studies now confirm that the amount of exercise you engage in plays an important role in determining whether or not you will develop atrial fibrillation—but this time, it cuts both ways. A sedentary lifestyle greatly increases your risk of atrial fibrillation; but, it turns out, so does the other extreme—overindulging in endurance exercise.

Sedentary Lifestyle

Many studies have shown a strong association between being sedentary and atrial fibrillation. Furthermore, improving your lifestyle can reduce atrial fibrillation. In 2015, the CARDIO-FIT study demonstrated that in patients with atrial fibrillation, an exercise program sufficient to substantially improve cardiopulmonary fitness levels was strongly associated with a reduction, and often elimination, of atrial fibrillation.

Too Much Exercise

On the other hand, several studies now have also documented that people who chronically engage in long bouts of endurance exercise (such as marathon runners) have a higher chance of developing atrial fibrillation—up to a five-fold increase.

What This Means for You

Not everyone who is overweight and sedentary and not everyone who habitually performs lots of endurance training will develop atrial fibrillation. But some people seem naturally prone to have atrial fibrillation (possibly due to genetic influences), and in these individuals either exercise extreme can be a problem.

From my own personal experience in treating them (and from at one time being one), endurance athletes tend to live in their own world. You generally can’t talk to them about the negatives that accompany their lifestyles.

But for the average person with atrial fibrillation, odds are higher that he or she is in the sedentary category, and therefore (in general) more amenable to reason. Talk to your healthcare provider about losing weight and beginning a reasonable exercise program, not merely to improve your general health, but also to help reduce or eliminate your atrial fibrillation.