Exercise and Dietary Lifestyle Intervention on Reducing Atrial Fibrillation Burden, Cardiac and Body Fat Mass.

Obesity is a major modifiable risk factor for atrial fibrillation and contributes to AF pathophysiology through systemic inflammation, autonomic imbalance, and adverse cardiac remodeling, including increased epicardial and atrial fat. Although exercise and weight reduction have been shown to improve AF-related outcomes, robust long-term randomized evidence integrating exercise, dietary intervention, objective AF burden monitoring, and cardiac magnetic resonance imaging is lacking. MOVE-AF is a parallel-group, open-label randomized controlled trial enrolling 158 overweight or obese adults with symptomatic paroxysmal or persistent AF. Participants will be randomized 1:1 to receive either a tailored exercise and dietary lifestyle intervention plus usual care or usual care alone. The intervention consists of individualized guideline-based aerobic and resistance exercise combined with dietary counseling aimed at reducing body fat mass. Main outcomes include AF burden assessed using continuous ambulatory rhythm monitoring, AF symptom severity assessed using validated questionnaires, and cardiac and total body fat mass assessed by cardiac MRI and body composition analysis. Secondary outcomes include cardiorespiratory fitness, muscle strength, cardiac autonomic nervous system function, cardiac remodeling, healthcare utilization, cost-effectiveness, and genetic risk modification of intervention effects. The study is conducted in accordance with the Declaration of Helsinki and applicable regulatory requirements. All participants will provide written informed consent before enrollment.