title: Left ventricular volume changes during supine exercise in young endurance athletes.
abstract: OBJECTIVE
  The primary objective of the study was to measure the relative left ventricular volumes and the changes in left ventricular ejection fraction during supine position from rest to exercise in young endurance athletes. The secondary objective was to examine if there were gender differences regarding the volume reply and ejection fraction with exercise.
  
  
  METHODS
  Sixty-five (35 female and 30 males) young healthy Swedish orienteers participated in the study. Left ventricular volume and ejection fraction changes between rest and submaximal supine bicycle exercise were measured with radionuclide ventriculography.
  
  
  RESULTS
  The mean left ventricular end-diastolic volume increased by 13% (P < 0.001) but there was no change in end-systolic volume. Stroke volume was found to increase by 21% (P < 0.001). Left ventricular ejection fraction increased significantly (>0.04 units) in 54% of the athletes from rest to exercise; 5% of the athletes showed a decrease in ejection fraction. A negative correlation was found between ejection fraction at rest and the difference in ejection fraction from rest to exercise (r = -0.38, P = 0.002). There were no gender differences in the left ventricular volume changes or ejection fraction.
  
  
  CONCLUSIONS
  During submaximal supine exercise, the adjustments in cardiac volumes in endurance athletes were small. There were no gender disparities concerning the left ventricular volume reply during exercise.
authors.affiliation: Department of Clinical Physiology and Centre for Clinical Research, Uppsala University, Central Hospital, Västerås, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Sundstedt
authors.forename: T
authors.initials: T
authors.lastname: Jonason
authors.forename: T
authors.initials: T
authors.lastname: Ahrén
authors.forename: S
authors.initials: S
authors.lastname: Damm
authors.forename: L
authors.initials: L
authors.lastname: Wesslén
authors.forename: E
authors.initials: E
authors.lastname: Henriksen
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D015635:Radionuclide Ventriculography / Q000379:methods; D012146:Rest / Q000502:physiology; D013177:Sports; D013318:Stroke Volume / Q000502:physiology*; D016277:Ventricular Function, Left / Q000502:physiology*