Nat. Rev. Cardiol. doi:10.1038/nrcardio.2016.173 Figure 2 Identification of individuals at risk of exercise-induced atrial fibrillation (AF) Figure 2 | Identification of individuals at risk of exercise-induced atrial fibrillation (AF). a | Representative large studies assessing the relative risk (RR) of exercise-induced AF according to the sex composition of the population (comparison of more-active with less-active individuals is shown). b | Relationship between exercise intensity and risk of AF in studies in which enough data were provided to estimate exercise intensity. Horizontal error bars represent the range of physical activity estimates, vertical bars the confidence interval of the risk of AF. c | Vigorous training duration (in years) in athletes at increased risk of AF. d | Age at which physical activity was assessed in the most representative studies. Positive studies (those with a finding that physical activity significantly increases the risk of AF) are represented by a green circle; negative studies (those that ruled out a significant proarrhythmic effect of exercise) are represented by a red circle. METS, metabolic equivalents; OR, odds ratio. Guasch, E. & Mont, L. (2016) Diagnosis, pathophysiology, and management of exercise-induced arrhythmias Nat. Rev. Cardiol. doi:10.1038/nrcardio.2016.173