DMD and Duchenne muscular dystrophy: We do not know whether this augmented activity can be detrimental in terms of heart failure, but it has been reported that ambulant Becker Muscular Dystrophy patients more often develop a dilated cardiomyopathy and that DMD carriers (with 50% of fibers not expressing dystrophin) have a normal motor activity, although they still develop a cardiomyopathy.