Exercise Reduces Risk of Atrial Fibrillation
Hunter-gatherer populations in which fairly high levels of exercise are the norm have excellent heart health in later life in comparison to more sedentary first world populations. Hunter-gatherers exhibit very little atrial fibrillation, for example. So it isn't all that surprising to see that greater levels of exercise in those first world populations correlate with reduced incidence of atrial fibrillation, one more item in the long list of reasons to undertake more rather than less physical activity.
Researchers focused on atrial fibrillation, a condition in which the heart's upper two chambers beat rapidly and irregularly instead of at a consistent pace. If left untreated, this can lead to stroke, heart failure, and other issues. While past studies have linked exercise to reduced risk of this type of arrhythmia, nearly all of these analyses have relied on participants' often inaccurate estimates of their own activity levels. The current study used data recorded from the fitness tracker Fitbit to objectively measure physical activity in more than 6,000 men and women across the United States. The results showed that those with higher amounts of weekly physical activity were less likely to develop atrial fibrillation. Notably, even modest amounts of moderate to vigorous exercise, which can range from taking a brisk walk or cleaning the house to swimming laps or jogging, were associated with reduced risk.
Specifically, study participants who averaged between 2.5 and 5 hours per week, the minimum amount recommended by the American Heart Association, showed a 60 percent lower risk of developing atrial fibrillation. Those who averaged greater than 5 hours had a slightly greater (65 percent) reduction. In the sole earlier study that used activity monitors to investigate atrial fibrillation, researchers provided Fitbit-style monitors to the participants and tracked them for only a week, an approach that may not have accurately captured their normal workout habits. The new investigation assessed participants for a full year and included only those who already owned the devices.