Meta-analysis links physical activity dose to U-shaped association with atrial fibrillation

A systematic review and meta-analysis in the European Journal of Preventive Cardiology examined the association between physical activity and atrial fibrillation (AF) across activity levels. Researchers searched four databases from January 1990 to June 2025, including 37 studies with 1,298,291 individuals. Eligible studies compared physical activity exposure with sedentary controls and assessed AF incidence or prevalence. Activity was standardised to metabolic equivalent of task hours per week (MET-hours/week).

In the general population, physical activity was associated with 22% lower odds of AF across 22 studies (OR 0.78; 95% CI 0.68–0.89). Athlete status was associated with higher odds across 15 studies (OR 2.74; 95% CI 1.72–4.39). Dose-response modelling using 26 studies and 1,022,790 individuals suggested the greatest reduction in odds at 26 MET-hours/week. Activity beyond 78 MET-hours/week was associated with increased odds, described by the authors as equivalent to 6–7 hours of endurance training weekly.

The findings suggest a U-shaped association relevant to discussions about exercise and AF. However, these associations do not establish causality, and the modelled threshold should not be interpreted as an individual exercise limit. Only the abstract was available; details of study quality, confounding adjustment and between-study heterogeneity could not be assessed.