title: Reproducibility of maximal exercise test data in the HERITAGE family study.
abstract: OBJECTIVE
  The reproducibility of responses to maximal cycle ergometer testing was determined using data from the HERITAGE Family study at four Clinical Centers in the United States and Canada.
  
  
  METHODS
  Reproducibility was determined from maximal exercise test data obtained a) on 2 d in a sample of 390 subjects (198 men and 192 women), b) across 4 d in an Intracenter Quality Control (ICQC) substudy with 55 subjects who were not part of the main study, and c) across 2 wk in a Traveling Crew Quality Control (TCQC) substudy with the same eight subjects who were tested at each of the four centers. Reproducibility was evaluated using technical errors, coefficients of variation (CV) for repeated measures, and intraclass correlation coefficients (ICC) for selected variables obtained on the main cohort, as well as on the ICQC and TCQC substudies.
  
  
  RESULTS
  With the exception of systolic and diastolic blood pressures and respiratory exchange ratio, all the other variables (heart rate, ventilation, VO2, and VCO2) were highly reproducible, with CV below 10% and ICC over 0.86. These results were similar to those previously reported on the same subjects at a submaximal power output associated with 60% VO2max. Results were consistent for the main cohort, the ICQC sample, the TCQC sample, and across all four Clinical Centers.
  
  
  CONCLUSIONS
  Day-to-day variations are small and reproducibility is high for maximal values of heart rate, ventilation, VO2 and VCO2 at each of the four Clinical Centers of the HERITAGE Family Study.
authors.affiliation: Indiana University, Bloomington, USA. jskinner@iupui.edu
authors.forename: J S
authors.initials: JS
authors.lastname: Skinner
authors.forename: K M
authors.initials: KM
authors.lastname: Wilmore
authors.forename: A
authors.initials: A
authors.lastname: Jaskolska
authors.forename: A
authors.initials: A
authors.lastname: Jaskolski
authors.forename: E W
authors.initials: EW
authors.lastname: Daw
authors.forename: T
authors.initials: T
authors.lastname: Rice
authors.forename: J
authors.initials: J
authors.lastname: Gagnon
authors.forename: A S
authors.initials: AS
authors.lastname: Leon
authors.forename: J H
authors.initials: JH
authors.lastname: Wilmore
authors.forename: D C
authors.initials: DC
authors.lastname: Rao
authors.forename: C
authors.initials: C
authors.lastname: Bouchard
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001794:Blood Pressure / Q000502:physiology; D002245:Carbon Dioxide / Q000097:blood; D015331:Cohort Studies; D003971:Diastole; D004562:Electrocardiography; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D016014:Linear Models; D008297:Male; D010100:Oxygen / Q000097:blood; D010807:Physical Endurance / Q000235:genetics; D011659:Pulmonary Gas Exchange / Q000502:physiology; D011786:Quality Control; D015203:Reproducibility of Results; D012119:Respiration; D013599:Systole
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen