The purpose of this study was to assess the validity of predicting maximal oxygen uptake % MathType!Translator!2!1!AMSTeX.tdl!TeX -- AMS-TeX! % MathType!MTEF!2!1!+- % feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaeWaaeaace % WGwbGbaiaacaqGpbWaaSbaaSqaaiaabkdacaqGTbGaaeyyaiaabIha % aeqaaaGccaGLOaGaayzkaaaaaa!3CE6! $$\left( {\dot V{\text{O}}_{{\text{2max}}} } \right)$$ from sub-maximal % MathType!Translator!2!1!AMSTeX.tdl!TeX -- AMS-TeX! % MathType!MTEF!2!1!+- % feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOvayaaca % Gaae4tamaaBaaaleaacaqGYaaabeaaaaa!3884! $$\dot V{\text{O}}_{\text{2}}$$ values elicited during a perceptually-regulated exercise test. We hypothesised that the strong relationship between the ratings of perceived exertion (RPE) and % MathType!Translator!2!1!AMSTeX.tdl!TeX -- AMS-TeX! % MathType!MTEF!2!1!+- % feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOvayaaca % Gaae4tamaaBaaaleaacaqGYaaabeaaaaa!3884! $$\dot V{\text{O}}_{\text{2}}$$ would enable % MathType!Translator!2!1!AMSTeX.tdl!TeX -- AMS-TeX! % MathType!MTEF!2!1!+- % feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOvayaaca % Gaae4tamaaBaaaleaacaqGYaGaaeyBaiaabggacaqG4baabeaaaaa!3B53! $$\dot V{\text{O}}_{{\text{2max}}}$$ to be predicted and that this would improve with practice. Ten male volunteers performed a graded exercise test (GXT) to establish % MathType!Translator!2!1!AMSTeX.tdl!TeX -- AMS-TeX! % MathType!MTEF!2!1!+- % feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOvayaaca % Gaae4tamaaBaaaleaacaqGYaGaaeyBaiaabggacaqG4baabeaaaaa!3B53! $$\dot V{\text{O}}_{{\text{2max}}}$$ followed by three sub-maximal RPE production protocols on a cycle ergometer, each separated by a period of 48 h. The perceptually-regulated trials were conducted at intensities of 9, 11, 13, 15 and 17 on the RPE scale, in that order. % MathType!Translator!2!1!AMSTeX.tdl!TeX -- AMS-TeX! % MathType!MTEF!2!1!+- % feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOvayaaca % Gaae4tamaaBaaaleaacaqGYaaabeaaaaa!3884! $$\dot V{\text{O}}_{\text{2}}$$ and HR were measured continuously and recorded at the end of each 4 min stage. Individual’s RPE values yielded correlations in the range 0.92–0.99 across the three production trials. There were no significant differences between measured % MathType!Translator!2!1!AMSTeX.tdl!TeX -- AMS-TeX! % MathType!MTEF!2!1!+- % feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOvayaaca % Gaae4tamaaBaaaleaacaqGYaGaaeyBaiaabggacaqG4baabeaaaaa!3B53! $$\dot V{\text{O}}_{{\text{2max}}}$$ (48.8 ml·kg−1·min−1) and predicted % MathType!Translator!2!1!AMSTeX.tdl!TeX -- AMS-TeX! % MathType!MTEF!2!1!+- % feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOvayaaca % Gaae4tamaaBaaaleaacaqGYaaabeaaaaa!3884! $$\dot V{\text{O}}_{\text{2}}$$ max values (47.3, 48.6 and 49.9 ml·kg−1·min−1, for trials 1, 2 and 3, respectively) when % MathType!Translator!2!1!AMSTeX.tdl!TeX -- AMS-TeX! % MathType!MTEF!2!1!+- % feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOvayaaca % Gaae4tamaaBaaaleaacaqGYaaabeaaaaa!3884! $$\dot V{\text{O}}_{\text{2}}$$ max was predicted from RPE values of 9–17. The same was observed when % MathType!Translator!2!1!AMSTeX.tdl!TeX -- AMS-TeX! % MathType!MTEF!2!1!+- % feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOvayaaca % Gaae4tamaaBaaaleaacaqGYaGaaeyBaiaabggacaqG4baabeaaaaa!3B53! $$\dot V{\text{O}}_{{\text{2max}}}$$ was predicted using RPE 9–15. Limits of agreement (LoA) analysis on actual and predicted % MathType!Translator!2!1!AMSTeX.tdl!TeX -- AMS-TeX! % MathType!MTEF!2!1!+- % feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOvayaaca % Gaae4tamaaBaaaleaacaqGYaGaaeyBaiaabggacaqG4baabeaaaaa!3B53! $$\dot V{\text{O}}_{{\text{2max}}}$$ values (from RPE 9–17) were (bias±1.96×SDdiff) 1.5±7.3, 0.2±4.9 and −1.2±5.8 ml·kg−1·min−1, for trials 1, 2 and 3, respectively. Corresponding LoA values for actual and predicted % MathType!Translator!2!1!AMSTeX.tdl!TeX -- AMS-TeX! % MathType!MTEF!2!1!+- % feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOvayaaca % Gaae4tamaaBaaaleaacaqGYaGaaeyBaiaabggacaqG4baabeaaaaa!3B53! $$\dot V{\text{O}}_{{\text{2max}}}$$ (from RPE 9–15) were 5.4±11.3, 4.4±8.7 and 2.3±8.4 ml·kg−1·min−1, respectively. The data suggest that a sub-maximal, perceptually-guided, graded exercise protocol can provide acceptable estimates of maximal aerobic power, which are further improved with practice in fit young males.