Incidence of VO2max Responders to Personalized versus Standardized Exercise Prescription

Introduction Despite knowledge of cardiorespiratory fitness (CRF) training responders and nonresponders, it is not well understood how the exercise intensity prescription affects the incidence of response. The purpose of this study was to determine CRF training responsiveness based on cohort-specific technical error after 12 wk of standardized or individually prescribed exercise and the use of a verification protocol to confirm maximal oxygen uptake (VO(2)max). Methods Sedentary adult participants (9 men, 30 women; 48.2 +/- 12.2 yr) completed exercise training on 3 d center dot wk(-1) for 12 wk, with exercise intensity prescribed based on standardized methods using heart rate reserve or an individualized approach using ventilatory thresholds. A verification protocol was used at baseline and 12 wk to confirm the identification of a true VO(2)max and subsequent relative percent changes to quantify CRF training responsiveness. A cohort-specific technical error (4.7%) was used as a threshold to identify incidence of response. Results Relative VO(2)max significantly increased (P < 0.05) from 24.3 +/- 4.6 to 26.0 +/- 4.2 and 29.2 +/- 7.5 to 32.8 +/- 8.6 mL center dot kg(-1)center dot min(-1) for the standardized and individualized groups, respectively. Absolute VO(2)max significantly increased (P < 0.05) from 2.0 +/- 0.6 to 2.2 +/- 0.6 and 2.4 +/- 0.8 to 2.6 +/- 0.9 L center dot min(-1) for the standardized and individualized groups, respectively. A significant difference in responsiveness was found between the individualized and standardized groups with 100% and 60% of participants categorized as responders, respectively. Conclusions A threshold model for exercise intensity prescription had a greater effect on the incidence of CRF training response compared with a standardized approach using heart rate reserve. The use of thresholds for intensity markers accounts for individual metabolic characteristics and should be considered as a viable and practical method to prescribe exercise intensity.