TY - JOUR T1 - Protecting against sedentary lifestyle, left atrial enlargement and atrial fibrillation JF - Open Heart JO - Open Heart DO - 10.1136/openhrt-2022-001962 VL - 9 IS - 1 SP - e001962 AU - Fabian Sanchis-Gomar AU - Carl J Lavie Y1 - 2022/02/01 UR - http://openheart.bmj.com/content/9/1/e001962.abstract N2 - Physical inactivity in contemporary obesogenic environments induces cardiac maladaptations, which causes a higher risk of atrial fibrillation (AF).1 Light-to-moderate physical activity (PA), however, is associated with a lower incidence of AF.1–3 Conversely, the long-term practice of strenuous endurance exercise increases the risk of AF in younger, middle-aged and older populations, particularly in highly competitive athletes,4 depicting a U-shaped curve (see figure 1).1 5 The precise causative mechanism/s of exercise-induced AF is still unknown.6 This type of exercising produces structural and functional cardiac adaptations, higher levels of oxidative stress, inflammation and adrenergic activation, ultimately predisposing to atrial fibrosis and AF.1Figure 1 Legend dose–response association between physical activity volume, AF risk, and left atrium enlargement based on Heitmann et al results. AF, atrial fibrillation; LA, left atrium.Left atrium (LA) dilation or LA enlargement (LAE) is thought to be a potential causative mechanism of exercise-related AF.7 8 In addition, there are likely differences in the aetiology and clinical presentation of AF between endurance athletes and the general (non-athletic) population, that is, … ER -