title: Just noticeable difference in perception of physical exertion during cycle exercise in young adult men and women.
abstract: 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 (VO2) 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 VO(2PEAK) within genders for VO2 (l · min(-1), %VO(2PEAK)) and PO (W, %SS). JND-B was significantly (P < 0.05) greater than JND-A for VO2 and PO, when expressed in absolute (l · min(-1), W) and relative units (%VO(2PEAK), %SS). Males exhibited greater JND values than females in absolute, but not relative, units. Subjects with lower and higher VT and VO(2)PEAK exhibited similar JND values. The JND can serve as an effective tool to measure perceptual acuity and to determine individual ability to self-regulate prescribed exercise intensities.
authors.affiliation: Department of Health Science, Lock Haven University of Pennsylvania, 401 N Fairview Street, Lock Haven, PA 17745, USA. luh2415@lhup.edu
authors.forename: Luke
authors.initials: L
authors.lastname: Haile
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Robertson
authors.forename: Elizabeth F
authors.initials: EF
authors.lastname: Nagle
authors.forename: Maressa P
authors.initials: MP
authors.lastname: Krause
authors.forename: Michael
authors.initials: M
authors.lastname: Gallagher
authors.forename: Christina M
authors.initials: CM
authors.lastname: Ledezma
authors.forename: Kristofer S
authors.initials: KS
authors.lastname: Wisniewski
authors.forename: Alex B
authors.initials: AB
authors.lastname: Shafer
authors.forename: Fredric L
authors.initials: FL
authors.lastname: Goss
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001642:Bicycling; D005080:Exercise Test; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000502:physiology*; D010101:Oxygen Consumption; D010465:Perception; D005082:Physical Exertion; D012123:Pulmonary Ventilation; D012737:Sex Factors; D013997:Time Factors; D055815:Young Adult