Take the plunge for your heart.  You don't need to be a Pisces for your heart, and the rest of you, to reap the benefits of swimming.
D002318:Cardiovascular Diseases / Q000517:prevention & control*; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D010809:Physical Fitness; D013550:Swimming / Q000502:physiology*; D016474:Weight-Bearing