title: Predicting max HR and the HR-VO2 relationship for exercise prescription in obesity.
abstract: This research derived regression equations for predicting maximal heart rate (MHR) and examined the relationship between relative oxygen consumption (VO2) and heart rate (HR) in obese (N = 86, body fat > 30%, hydrostatic weighing) compared with normal-weight (N = 51, body fat < or = 30%) adults. Simultaneous measurements of HR and VO2 were recorded at rest and every minute during a maximal graded exercise test. When MHR was regressed on age, two distinct equations for the obese and normalweights were generated. The relationship between %MHR and %max VO2 was similar between groups (r = 0.83, obese; r = 0.87 normalweights). Likewise, when %max VO2 was regressed on %max heart rate range similar equations were derived fro the obese (r = 0.81) and normalweights (r = 0.84). Correlation between Karvonen's predicted HR at a submaximal VO2 and the true HR at that VO2 was 0.88, regardless of adiposity. These data indicate that when predicting MHR in normalweights the equation 220-Age can be used, but for obese individuals the equation 200-0.5 x Age is more accurate; each having 12 as a standard error of estimate. Once MHR is determined, either the straight percentage technique or Karvonen's method would be appropriate for prescribing exercise intensity for both populations.
authors.affiliation: Department of Kinesiology, Indiana University, Bloomington 47405.
authors.forename: W C
authors.initials: WC
authors.lastname: Miller
authors.forename: J P
authors.initials: JP
authors.lastname: Wallace
authors.forename: K E
authors.initials: KE
authors.lastname: Eggert
mesh_terms: D000273:Adipose Tissue / Q000033:anatomy & histology; D000328:Adult; D001794:Blood Pressure / Q000502:physiology; D015992:Body Mass Index; D001835:Body Weight; D005080:Exercise Test; D005081:Exercise Therapy; D005260:Female; D005544:Forecasting; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D010101:Oxygen Consumption / Q000502:physiology; D012044:Regression Analysis; D015203:Reproducibility of Results