The Safety of Exercise in Individuals With Cardiomyopathy.

The cardiomyopathies are a heterogeneous group of primary myocardial diseases characterized by a propensity to fatal arrhythmias and are the leading cause of sudden cardiac death in young athletes. Apart from the underlying pathologic substrate, a combination of neurohormonal, mechanical, and oxidative stressors; dehydration; electrolyte abnormalities; and acid-base disturbances may trigger fatal arrhythmias during intensive exercise. Current consensus-based documents recommend that affected athletes abstain from most competitive sports, with the exception of those involving minimal dynamic or static components, to minimize the risk of sudden cardiac death. This article aims to describe the rationale underlying current recommendations and provides guidance for recreational exercise in many asymptomatic individuals. The article concludes with pragmatic recommendations for symptomatic patients with cardiomyopathy in whom physical activity is associated with beneficial effects on the quality and, possibly, the quantity of life.