Atrial fibrillation, often referred to as AFib, is the most common type of irregular heartbeat in the U.S., currently affecting more than 2 million Americans. AFib increases risk of stroke by five times, and as with most chronic diseases, prevention is the best medicine. However, few studies have investigated the relationship between regular exercise—a cornerstone of good health—and risk for atrial fibrillation.
To learn more on the issue, researchers analyzed data from the Henry Ford Exercise Testing (FIT) Project, which used a simple treadmill stress test to assess patients’ health and fitness, and published their findings in the medical journal Circulation. Stress tests help measure how the heart responds to extra work and can help diagnose a number of conditions, such as chest pain and heart disease.
Nearly 70,000 healthy middle-aged adults underwent exercise testing between 1991 and 2009 and were followed for five and a half years. During follow-up, roughly 7% of patients were diagnosed with atrial fibrillation.
Based on results of stress tests, researchers found that the more fit patients were, the lower their risk of AFib. In fact, each 1-point increase in MET (a measure of fitness called a metabolic equivalent) was linked to 7% lower risk of atrial fibrillation. Interestingly, this relationship was especially strong in obese patients, suggesting that fitness makes an even greater impact in reducing cardiovascular risk in obese individuals.
This is the first study of its kind to establish a link between fitness and reduced risk for AFib. Although it’s well-established that exercise reduces risk for a number of heart conditions, this study confirms that regular physical activity helps lower risk for atrial fibrillation as well.
Findings are especially important, as the relationship between AFib and exercise is somewhat controversial. Past studies have linked high levels of vigorous activity to increased risk of AFib, and exercise can aggravate AFib in certain patients. However, most Americans fail to get the recommended levels of exercise, and risk associated with physical activity is low for most healthy adults. As authors explain, reduced risk of AFib offers yet another reason to participate in regular physical activity and promote better heart health.