title: Polarcardiographic responses to maximal exercise and to changes in posture in healthy middle-aged men.
mesh_terms: D000328:Adult; D000367:Age Factors; D001794:Blood Pressure; D006321:Heart / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D005082:Physical Exertion; D011187:Posture; D012119:Respiration