Physical Activity in Arrhythmogenic Cardiomyopathy: From Trigger to Therapeutic Dilemma.

Arrhythmogenic cardiomyopathy (ACM) is highly sensitive to environmental influences, with physical exercise emerging as one of the most important determinants of disease expression. Growing evidence indicates that high-intensity and endurance exercise accelerate structural remodelling, promote inflammatory myocardial injury, and increase the incidence of malignant ventricular arrhythmias in genetically predisposed individuals. These effects extend beyond acute exertion, as cumulative exercise exposure contributes to the development of a persistent arrhythmogenic substrate that may sustain risk even after cessation of competitive sport. In contrast, available data suggest that low-intensity physical activity does not confer the same degree of arrhythmic burden and may support overall cardiovascular and functional health when carefully prescribed. This review integrates mechanistic insights, clinical cohort data, and current guideline recommendations to provide a balanced framework for exercise counselling in ACM. Rather than advocating complete physical inactivity, this approach differentiates high-risk endurance or competitive exercise from carefully selected low-intensity recreational activity and emphasizes individualized, shared decision-making. Thus, understanding the interaction among genetic substrate, exercise intensity, and systemic stressors is essential for optimizing personalized activity recommendations and improving long-term outcomes in this vulnerable population.