Exercise and even strenuous exercise is clearly associated with enormous benefits to the heart for the vast majority of people. However, there is a minority with underlying problems where vigorous exercise can trigger arrhythmia. People engaged in moderate physical activity have a lower risk of atrial fibrillation than people who exercise at high intensity.
Research suggests that many years of endurance training can alter the structure and function of the heart in a way that increases the risk of atrial fibrillation, says researcher Bente Morseth at Faculty of Health Sciences and the Faculty of sport, tourism and Social Studies, University of Tromsø. In his study, 20.484 participants documented their resting heart rate and self-reported physical activity level. In 2010 it was concluded that 750 of the participants had atrial fibrillation. After filtering the data via for age, sex, smoking status, BMI, height and disease.
It was concluded that those who had participated in moderate physical activity in the form of walking, cycling or other light exercise, at least 4 hours each week had the lowest risk of fibrillation. The risk was 19 percent lower for those who were moderately physically active than those who said they were very physically active. Participants who reported to take part in at least 4 hours of recreational sport per week were suggested to be at the same risk as those who are inactive.
Despite the concern about extreme exercise, there is not much reason for the average person to worry. Exercising is far better than being inactive.
Morseth B,Graff-Iversen S,Jørgensen L,Nyrnes A,Thelle DS,Vestergaard P,Løchen ML, Jacobsen BK,. Physical activity, resting heart rate, and atrial fibrillation: the Tromsø Study, Eur Heart J.2016 Mar 10.
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