title: Endurance Exercise-Induced Cardiac Remodeling: Not All Sports Are Created Equal.
abstract: BACKGROUND
  The term endurance sport (ES) is broadly used to characterize any exercise that requires maintenance of high cardiac output over extended time. However, the relative amount of isotonic (volume) versus isometric (pressure) cardiac stress varies across ES disciplines. To what degree ES-mediated cardiac remodeling varies, as a function of superimposed isometric stress, is uncertain. The aim of this study was to compare the cardiac remodeling characteristics associated with two common yet physiologically distinct forms of ES.
  
  
  METHODS
  Healthy competitive male long-distance runners (high isotonic, low isometric stress; n = 40) and rowers (high isotonic, high isometric stress; n = 40) were comparatively studied after 3 months of sport-specific exercise training with conventional and speckle-tracking two-dimensional echocardiography.
  
  
  RESULTS
  Rowers demonstrated dilated left ventricular (LV) volumes and elevated LV mass (i.e., eccentric LV hypertrophy), whereas runners demonstrated normal LV mass (runners, 88 ± 11 g/m(2); rowers, 108 ± 13 g/m(2); P < .001) despite comparatively larger LV volumes (runners, 101 ± 10 mL/m(2); rowers, 89 ± 13 mL/m(2); P < .001) consistent with eccentric LV remodeling. Increasing LV mass was associated with increased reliance on early diastolic filling (LV mass vs E'/A' ratio, R = 0.47, P < .001) indicating "mass-dependent" diastolic function. Right ventricular dilation of similar magnitude and LV systolic function, as assessed by numerous complementary indices, were similar in both groups.
  
  
  CONCLUSIONS
  Cardiac adaptations differ significantly as a function of ES discipline. Further work is required to determine the mechanisms for this differential adaptation, to develop definitive ES discipline-specific normative values, and to evaluate the optimal therapeutic use of specific ES disciplines among patients with common cardiovascular diseases.
authors.affiliation: Cardiovascular Performance Program, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Meagan M
authors.initials: MM
authors.lastname: Wasfy
authors.affiliation: Cardiovascular Performance Program, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Rory B
authors.initials: RB
authors.lastname: Weiner
authors.affiliation: Harvard University Health Services, Cambridge, Massachusetts.
authors.forename: Francis
authors.initials: F
authors.lastname: Wang
authors.affiliation: Harvard University Health Services, Cambridge, Massachusetts.
authors.forename: Brant
authors.initials: B
authors.lastname: Berkstresser
authors.affiliation: Cardiovascular Performance Program, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Gregory D
authors.initials: GD
authors.lastname: Lewis
authors.affiliation: Cardiovascular Performance Program, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: James R
authors.initials: JR
authors.lastname: DeLuca
authors.affiliation: Cardiovascular Performance Program, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Adolph M
authors.initials: AM
authors.lastname: Hutter
authors.affiliation: Cardiovascular Performance Program, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Picard
authors.affiliation: Cardiovascular Performance Program, Massachusetts General Hospital, Boston, Massachusetts; Harvard University Health Services, Cambridge, Massachusetts. Electronic address: abaggish@partners.org.
authors.forename: Aaron L
authors.initials: AL
authors.lastname: Baggish
mesh_terms: D000293:Adolescent; D003430:Cross-Sectional Studies; D015150:Echocardiography, Doppler; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D009200:Myocardial Contraction / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology*; D012420:Running / Q000502:physiology*; D016277:Ventricular Function, Left / Q000502:physiology*; D020257:Ventricular Remodeling
keywords: Cardiac remodeling; Diastolic function; Endurance exercise; Left ventricular hypertrophy