title: Cardiac MRI reference values for athletes and nonathletes corrected for body surface area, training hours/week and sex.
abstract: OBJECTIVE
  To establish cardiac MRI reference values for endurance athletes and nonathletes, and study the impact of variables related to ventricular volumes and wall-mass.
  
  
  METHODS
  Three hundred and thirty-six prospectively recruited healthy individuals aged 18-39 years (mean age 26+/-6 years, 46% women) underwent cardiac MRI: 79 elite athletes (exercising >18 h/week), 143 regular athletes (9-18 h/week), and 114 matched nonathletes (< or =3 h/week).
  
  
  RESULTS
  Body surface area corrected right (RV) and left ventricular (LV) end-diastolic volume (EDV ml/m2) and wall mass (g/m2) were significantly higher (P<0.0005) in regular/elite athletes than in nonathletes (nonathlete/regular-athlete/elite-athlete; men RV-EDV 111/136/144, RV-wall mass 12/14/15, LV-EDV 101/123/129, LV-wall mass 48/62/69; women RV-EDV 96/115/118, RV-wall mass 10/13/14, LV-EDV 90/107/107, LV-wall mass 34/46/50). Male sex, body surface area, and training hours/week increase ventricular volume and wall mass. In elite athletes, short-axis RV diameter exceeded 50 mm in 49/16% (men/women), and LV diameter exceeded 60 mm in 55/16% (men/women). Interventricular septal-wall thickness was 13-15 mm in 5% regular and 15% elite male athletes.
  
  
  CONCLUSIONS
  Cardiac MRI reference values show increased ventricular volumes, diameters, wall mass, and wall thickness for endurance athletes compared with nonathletes. High training hours/week and male sex result in an increased overlap with standard thresholds for cardiomyopathy. To help prevent inconclusive reports, the 95th percentile reference values can be used as an alternative to standard upper limits used for the general population.
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Heidelberglaan, Utrecht, The Netherlands. n.prakken@umcutrecht.nl
authors.forename: Niek H
authors.initials: NH
authors.lastname: Prakken
authors.forename: Birgitta K
authors.initials: BK
authors.lastname: Velthuis
authors.forename: Arco J
authors.initials: AJ
authors.lastname: Teske
authors.forename: Arend
authors.initials: A
authors.lastname: Mosterd
authors.forename: Willem P
authors.initials: WP
authors.lastname: Mali
authors.forename: Maarten J
authors.initials: MJ
authors.lastname: Cramer
mesh_terms: D000222:Adaptation, Physiological; D000293:Adolescent; D000328:Adult; D056352:Athletes; D001830:Body Surface Area; D005260:Female; D006352:Heart Ventricles / Q000033:anatomy & histology*; D006801:Humans; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008403:Mass Screening / Q000379:methods*; D009929:Organ Size; D010807:Physical Endurance; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012016:Reference Values; D012737:Sex Factors; D013997:Time Factors; D055815:Young Adult