Accuracy of prediction equations to estimate submaximal V̇O₂ during cycle ergometry: The HERITAGE Family Study

It was hypothesized that more accurate equations for estimating submaximal V̇O₂ during cycle ergometry could be developed if more independent variables were used in the equation. Purpose: The purposes of this study were: (1) to develop new equations for estimating submaximal V̇O₂ during cycle ergometry; and (2) to examine the accuracy of the newly developed equations and those of the American College of Sports Medicine (1995), Berry et al. (1993), Lang et al. (1992), Latin and Berg (1994), and Londeree et al. (1997). Methods: Subjects (715 men and women, ages 16-65 yr, from the HERITAGE Family Study) completed a maximal cycle ergometry test, two submaximal trials at 50 W and 60% of V̇O(2max), hydrostatic weighing, and stature and body mass measures before and after 20 wk of cycle ergometry training. Regression analysis generated prediction equations using pretraining data from the 60% trials. Results: No equation with more independent variables was better than an equation that used only power output. This equation, HERITAGE-1, with only power output was cross-validated using the 'jackknife' technique. Paired t-tests, mean differences, SEEs, and Es were used to compare the V̇O₂ estimated by HERITAGE-1 and those of previously published equations with the measured V̇O₂ at 60% of V̇O(2max). Conclusions: HERITAGE-1 was slightly better than the equations of ACSM, Lang et al., and Latin and Berg using pretraining data but was not better when using post-training data. All four of these equations were superior to the equations of Berry et al. and Londeree et al.