Strength Training Shows No Association with Ventricular Arrhythmia in ACM Patients per JACC Registry Analysis

The retrospective analysis relied on structured phone interviews capturing exercise history from age 10 onward, classifying participants into endurance, strength, dual, or sedentary groups based on self-reported weekly hours. Endurance athletes showed 58% higher arrhythmia likelihood while strength athletes did not; 55% of the cohort experienced events, often at enrollment following diagnosis. This aligns with prior observational data in Circulation: Genomic and Precision Medicine on desmosomal mutation carriers where pressure overload from resistance exercise produced less fibrofatty remodeling than volume overload from endurance activity. The registry design captured U.S. adults with median enrollment age 34, yet could not establish temporality between exercise and first events. Guidelines from the 2022 ESC sports cardiology document already recommend individualized counseling; this study supplies the first quantitative separation of exercise modalities in ACM. Next steps require prospective monitoring with objective activity trackers to confirm safety thresholds and assess long-term ventricular function changes.