Perceptually Regulated Exercise Test Allows Determination of V˙O2max and Ventilatory Threshold But Not Respiratory...

This study aimed to investigate the differences in maximal oxygen uptake (V̇O_2max) and submaximal thresholds between a standard graded exercise test (GXT) and a perceptually regulated graded exercise test (PRGXT) in trained runners. Eleven well-trained middle- to long-distance runners performed both tests in a randomized order. PRGXT used incremental "clamps" of rating of perceived exertion (RPE) over 10×1-min stages on an automated treadmill equipped with a sonar sensor allowing them to change their running speed instantly and in a natural way. GXT used fixed 1 km^.h^-1 increment every minute. Ventilatory threshold (VT) and respiratory compensation point (RCP) were determined using ventilatory equivalents. No differences were found in V̇O_2max (68.0 (5.3) vs. 69.5 (5.9) ml·min^-1·kg^-1, p=0.243), minute ventilation (V̇E) (159.4 (35.0) vs. 162.4 (33.7) l·min^-1, p=0.175), heart rate (HR) (188.4 (6.9) vs. 190.7 (5.2) bpm, p=0.254) and speed (21.0 (1.7) vs. 21.1 (2.3) km·h-¹, p=0.761) between GXT and PRGXT. At VT, there were no significant differences between GXT and PRGXT for any outcome variables. For 8 of 11 subjects, it was not possible to determine RCP from ventilatory equivalent in PRGXT. GXT appears more relevant for a comprehensive gas analysis in trained runners.