Effect of Aerobic Interval Training on Atrial Fibrillation Burden

Inclusion Criteria: 1. Age range: 18-74 years; 2. Patients with non-permanent atrial fibrillation; 3. Resting heart rate ≤110 beats/min; 4. No history of receiving a formal exercise prescription within the past six months; 5. Willing to participate in this study, provide written informed consent, and agree to comply with follow-up procedures. Exclusion Criteria: 1. History of myocardial infarction, endocarditis/myocarditis/pericarditis, stroke (ischemic/hemorrhagic), pulmonary embolism, lower extremity venous thrombosis, or cardiac surgery within the past 6 months; 2. Moderate to severe pulmonary arterial hypertension, moderate to severe valvular heart disease, hypertrophic cardiomyopathy, aortic stenosis/dilation/dissection/intramural hematoma, congenital heart disease; 3. Heart failure (NYHA class III-IV) or acute exacerbation of heart failure within the past 3 months; 4. Unstable angina or severe coronary artery disease without revascularization; 5. Concurrent severe arrhythmias * frequent multifocal premature ventricular contractions * ventricular tachycardia, ventricular fibrillation * high-degree or complete atrioventricular block * ventricular asystole lasting more than 5 seconds 6. Uncontrolled hypertension or hypotension; 7. Severe renal or hepatic dysfunction * Stage 5 chronic kidney disease, defined as glomerular filtration rate \<15 ml/(min•1.73 m2) or requiring dialysis; * Patient with alanine aminotransferase (ALT) or aspartate aminotransferase (AST) levels greater than or equal to 5 times the upper limit of normal as defined by the center during screening; 8. Hypoxemia or severe lung disease; 9. Lower extremity arterial stenosis or musculoskeletal disease preventing exercise training; 10. Intracardiac thrombus; 11. Pregnancy; 12. Cognitive impairment preventing study cooperation; 13. Severe anemia, infection, electrolyte disturbances, hyperthyroidism; 14. Planned atrial fibrillation ablation during the study period; 15. Post-implantation of pacemaker or ICD; 16. Inability to use smart devices; 17. Concurrent cancer or autoimmune or systemic inflammatory disease; 18. Regular moderate-to-high intensity exercise habits (≥2 sessions of high-intensity endurance training per week or ≥3 sessions of moderate-intensity endurance training