A perceptually regulated, graded exercise test predicts peak oxygen uptake during treadmill exercise in active and sedentary participants

The validity of predicting peak oxygen uptake (\( \dot{V}{\text{O}}_{{ 2 {\text{peak}}}} \)) in sedentary participants from a perceptually regulated exercise test (PRET) is limited to two cycle ergometry studies. We assessed the validity of a treadmill-based PRET. Active (n = 49; 40.7 ± 13.8 years) and sedentary (n = 26; 33.4 ± 13.2 y) participants completed two PRETS (PRET 1 and PRET2), requiring a change in speed or incline corresponding to ratings of perceived exertion (RPE) 9, 11, 13 and 15. Extrapolation of RPE: \( \dot{V}{\text{O}}_{2} \) data to RPE 19 and 20 from the RPE 9–13 and 9–15 ranges were used to estimate \( \dot{V}{\text{O}}_{{ 2 {\text{peak}}}} \), and compared to \( \dot{V}{\text{O}}_{{ 2 {\text{peak}}}} \) from a graded exercise test (GXT). The \( \dot{V}{\text{O}}_{2} \) :heart rate (HR) data (≥RPE 15) from the GXT were also extrapolated to age-predicted maximal HR (HRmax_pred) to provide further estimation of \( \dot{V}{\text{O}}_{{ 2 {\text{peak}}}} \). ANOVA revealed no significant differences between \( \dot{V}{\text{O}}_{{ 2 {\text{peak}}}} \) predictions from the RPE 9–15 range for PRET 1 and PRET 2 when extrapolated to RPE 19 in both active (54.3 ± 7.4; 52.9 ± 8.1 ml kg⁻¹ min⁻¹) and sedentary participants (34.1 ± 10.2; 34.2 ± 9.6 ml kg⁻¹ min⁻¹) and no difference between the HRmax_pred method and measured \( \dot{V}{\text{O}}_{{ 2 {\text{peak}}}} \) from the GXT for active (53.3 ± 10.0; 53.9 ± 7.5 ml kg⁻¹ min⁻¹, respectively) and sedentary participants (33.6 ± 8.4, 34.4 ± 7.0 ml kg⁻¹ min⁻¹, respectively). A single treadmill-based PRET using RPE 9–15 range extrapolated to RPE 19 is a valid means of predicting \( \dot{V}{\text{O}}_{{ 2 {\text{peak}}}} \) in young and middle to older-aged individuals of varying activity and fitness levels.