title: Effects of simulated altitude and exercise upon ECGs of young black men.
abstract: Twenty-five healthy black men between 17 and 21 years of age were evaluated. Their resting and exercise electrocardiograms were recorded at simulated sea level and at a simulated altitude of 4,000 m. Sea level exercise caused a reduction in the amplitudes of R waves and a lowering of J points. Exercise at a simulated altitude of 4,000 m caused a lowering of the J point in several leads and a reduction of the R wave amplitude in lead aVF. Hypoxia caused a reduction in the amplitudes of the T waves and a lowering of the J points in several leads. These effects of exercise and altitude, to a great extent, eliminated the appearance of "early repolarization," which is very common among young black men.
authors.affiliation: Department of Pediatrics, William Beaumont Army Medical Center, El Paso, TX 79920.
authors.forename: W
authors.initials: W
authors.lastname: Pearl
authors.forename: R J
authors.initials: RJ
authors.lastname: Zeballos
authors.forename: G
authors.initials: G
authors.lastname: Gregory
authors.forename: S M
authors.initials: SM
authors.lastname: Connery
authors.forename: I M
authors.initials: IM
authors.lastname: Weisman
mesh_terms: D000328:Adult; D000531:Altitude; D044383:Black People; D004562:Electrocardiography; D015444:Exercise / Q000502:physiology*; D006321:Heart / Q000502:physiology*; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology; D008297:Male