title: Ask the doctors.  Many years ago, I practiced interval training.  I pushed myself for three to four minutes up to five times during a work out.  I want to start working out again, but wonder if this kind of training would be safe for me.  I'm a lot older now and have some heart disease.
authors.forename: Thomas
authors.initials: T
authors.lastname: Lee
authors.forename: Richard
authors.initials: R
authors.lastname: Lee
mesh_terms: D015444:Exercise / Q000502:physiology*; D006304:Health Status; D006331:Heart Diseases / Q000517:prevention & control; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D010807:Physical Endurance / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology; D016138:Walking / Q000502:physiology