We hypothesized that a large proportion of the error of VO<sub>2</sub>max prediction comes from individual differences in heart rate responses to submaximal exercise, and that if these differences could be decreased the accuracy of VO<sub>2</sub>max prediction would increase. Eighty (43 male, 37 female) sedentary to highly trained, healthy volunteers first completed a self-report physical activity assessment (Lo-Par), and then performed a modified YMCA protocol with 4-minute stages, a second submaximal test involving an individualized ramp submaximal protocol that was terminated at 80 of their cycle ergometer age-predicted maximum heart rate. Exercise and five-minute recovery heart rate data were collected. A ramp cycle ergometer protocol with expired gas analysis was used to measure actual VO<sub>2</sub> max. Multiple regression analysis produced a model resulting in an *R²* = 0.867 and SEE = 4.23 mL/kg/min, with a prediction equation as follows: `VO₂ max (mL/kg/min) = 46.103 + (-0.353*Body Weight) + (0.683*Watts/min) + (-5.995*Gender) + (0.165*Delta Recovery Heart Rate) + (2.816*Recovery Heart Rate Non-Linear K) + (0.0138*Lo-PAR Exercise) + 4.234`. T-test statistics showed no statistically significant differences between observed and predicted VO<sub>2</sub>max. Mean difference between YMCA, ACSM, and Astrand-Ryhming Nomogram estimated VO<sub>2</sub> max and observed VO<sub>2</sub> max were significant. However, the new equation did not decrease the error of prediction to the extent hypothesized
