Abstract

The purpose of this investigation was to crossvalidate 2 equations that use the ratio of maximal heart rate (HRmax) to resting HR (HRrest) for predicting maximal oxygen consumption (V[Combining Dot Above]O2max) in white and black men. One hundred and nine white (n = 51) and black (n = 58) men completed a maximal exercise test on a treadmill to determine V[Combining Dot Above]O2max. The HRrest and HRmax were used to predict V[Combining Dot Above]O2max via the HRindex and HRratio equations. Validity statistics were done to compare the criterion versus predicted V[Combining Dot Above]O2max values across the entire cohort and within each race separately. For the entire group, V[Combining Dot Above]O2max was significantly overestimated with the HRindex equation, but the HRratio equation yielded no significant difference compared with the criterion. In addition, there were no significant differences shown between V[Combining Dot Above]O2max and either HR-based prediction equation for the white subgroup. However, both equations significantly overestimated V[Combining Dot Above]O2max in the black group. Furthermore, large standard error of estimates (ranging from 6.92 to 7.90 ml/kg/min), total errors (ranging from 8.30 to 8.62 ml/kg/min), and limits of agreement (ranging from upper limits of 16.65 to lower limits of -18.25 ml/kg/min) were revealed when comparing the predicted to criterion V[Combining Dot Above]O2max for both the groups. Considering the results of this investigation, the HRratio and HRindex methods appear to crossvalidate and prove useful for estimating the mean V[Combining Dot Above]O2max in white men as a group but not for an age-matched group of black men. However, because of inflated values for error, caution should be exercised when using these methods to predict individual V[Combining Dot Above]O2max. Verf.-Referat