Echocardiographic assessment of the left ventricle of endurance athletes just before and after exercise.
Fourteen normal subjects and 10 marathon runners were studied using postexercise echocardiography to assess left ventricular (LV) wall thickness, afterload and systolic performance. Cuff systolic blood pressures and M-mode echocardiographic recordings were obtained in the supine position before and within 2 minutes of termination of maximal treadmill exercise. Both groups had increased LV dimensional shortening (% fractional shortening) and stroke volume after exercise, although runners had larger increases compared to untrained normal subjects (p less than 0.05). Preload, as estimated by LV end-diastolic dimension, was greater in runners compared to normal subjects at rest (52 vs 48 mm, p less than 0.05). However, preload did not change after exercise in either group. Afterload, estimated by LV end-systolic wall stress, decreased after exercise in both groups; however, runners had lower afterload at rest and immediately after exercise compared to normal subjects (p less than 0.05). The runners' greater LV end-systolic wall thickness appears to account for their lower afterload. Data indicate that marathon runners have lower afterload at rest and greater decrease in afterload after maximal exercise, compared to untrained normal subjects.
Percy
R F
RF
Division of Cardiology, University Hospital of Jacksonville, Florida 32209.
Conetta
D A
DA
Miller
A B
AB
D000328:Adult; D004452:Echocardiography; D005260:Female; D006352:Heart Ventricles / Q000033:anatomy & histology; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D010806:Physical Education and Training; D010807:Physical Endurance / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology*; D012016:Reference Values; D012420:Running; D016276:Ventricular Function