Just noticeable difference in perception of physical exertion during cycle exercise in young adult men and women

The purpose of this investigation was to describe the just noticeable difference (JND) in perceived exertion during cycle exercise. Males ( n = 20) and females ( n = 26) (21.4 ± 3.1 year) performed load-incremented cycle exercise to peak intensity. At the end of each minute, subjects rated their overall-body perceived exertion using the OMNI (0–10) rating of perceived exertion (RPE) scale. Individual regression derived the power output (PO) corresponding to RPE 5. This PO served as the standard stimulus (SS). On a separate occasion, four 5-min cycling bouts were performed with 5 min rest between bouts. During bouts 1 and 3 subjects cycled at the SS. During bouts 2 and 4 subjects adjusted the resistance to achieve a level of exertion just noticeably above/below the SS. The difference in final 30-s oxygen consumption ( V O 2 ) and PO between each JND bout and the previous SS were the above (JND-A) and below (JND-B) perceived exertion JNDs. JND-A and JND-B were compared between genders and between subjects exhibiting lower versus higher ventilatory threshold (VT) and V O 2PEAK within genders for V O 2 (l·min −1 , % V O 2PEAK ) and PO (W, %SS). JND-B was significantly ( P