Effect of deception and expected exercise duration on psychological and physiological variables during treadmill running and cycling ROGER ESTON, a,b RALPH STANSFIELD, b PAUL WESTOBY, b and GAYNOR PARFITT a a School of Health Sciences, University of South Australia, Adelaide, Australia b School of Sport and Health Sciences, University of Exeter, Exeter, UK Abstract Effects of deception and expected duration on the rating of perceived exertion (RPE), affect, and heart rate (HR) were examined during treadmill (n = 12) and cycling (n = 8) exercise. Participants completed three conditions: (1) 20 MIN— exercise for 20 min, stop after 20 min; (2) 10 MIN—exercise for 10 min, in 10th min be told to exercise for 10 min more; and (3) UNKNOWN—no information about duration. Intensities were set at 70% and 65% of peak oxygen uptake for treadmill and cycling, respectively. RPE increased (treadmill) and affect decreased (treadmill and cycling) in the absence of changes in HR and oxygen uptake in the 10 MIN conditions. These changes suggest a disruption to a feed-forward/ feedback system. The lower HR in the UNKNOWN conditions suggests a subconscious attempt to conserve energy when the duration of the exercise task is unknown. Descriptors: Perceived exertion, Affect, Deception, Exercise Humans possess a remarkable ability to sense the strain, aches, and degree of effort and fatigue resulting from physical work. Borg (1998) has emphasized that the antecedents of perceived exertion include the memory of exercise or physical work experiences and the emotions associated with them. In an extension of Ulmer’s (1996) concept of teleoanticipation, Noakes (2008) proposed that perceived exertion links into a complex feed-forward/feedback system. This has been used to explain why perceived exertion is related to the proportion of time or distance remaining in pacing studies (Faulkner, Parfitt, & Eston, 2008; Joseph et al., 2008; Noakes, 2004; Pires et al., 2011) or where the workload is fixed under variable conditions of fatigue (Eston, Faulkner, St Clair Gibson, Noakes, & Parfitt, 2007), ambient temperature (Crewe, Tucker, & Noakes, 2008), or carbohydrate availability (Lima-Silva et al., 2011). Tucker (2009) suggested that a conscious rating of perceived exertion (RPE—the verbal manifestation of the inte- grated physiological and psychological cues) is continually matched to a subconscious “template” RPE. It is proposed that if there is a mismatch between the template and conscious RPE, then the exercise work rate will need to be altered until a match is obtained for appropriate pacing to be maintained to the end (the “anchor” point). Studies have demonstrated that if the expected duration is altered, such as in deception studies (e.g., Ansley, Schabort, St Clair Gibson, Lambert, & Noakes, 2004; Baden, Warwick-Evans, & Lakomy, 2004; Baden, Mclean, Tucker, Noakes, & St Clair Gibson, 2005; Faulkner, Arnold, & Eston, 2010), perceived exer- tion, and its potential scalar properties, are disrupted. For example, when anticipated running time was unexpectedly shortened, reported RPE was significantly lower than in a condition of the same duration and intensity (Baden et al., 2004). Further, when running time was extended beyond the anticipated time, RPE increased and affect decreased (Baden et al., 2005). In contrast, in an unknown duration task, the physiological cost of exercise was reduced (i.e., exercise economy was improved) even though RPE remained unchanged (Baden et al., 2005). The changes in RPE, when exercise duration was extended or shortened, were in line with Tucker’s (2009) model. However, his model would also have predicted a lower RPE in the unknown- duration condition to avoid premature fatigue. The better running economy in the unknown condition could be argued to represent an intelligent adaptation to the imposed condition. The precise mecha- nism for this is unclear, but, without an end point and with a fixed intensity, participants performed more efficiently over the 20-min duration than in the other conditions. Given the relative paucity of research in this area, the objectives of the two studies reported in this paper were to further explore the effect of deception on perceptual and physiological variables across two exercise modes (treadmill running and cycling). It was hypothesized that (1) there would be an increase in the RPE and a decrease in affect at the point, or soon after the point at which the true running and cycling time was revealed; and (2) RPE would be lower in the unknown duration task. Further, as we were intrigued by the apparent change in running economy, which may be asso- ciated with changes in psychological state (Crews, 1992), we were Address correspondence to: Prof. Roger Eston, School of Health Sci- ences, University of South Australia, Adelaide, SA 5000. E-mail: roger.eston@unisa.edu.au Psychophysiology, 49 (2012), 462–469. Wiley Periodicals, Inc. Printed in the USA. Copyright © 2012 Society for Psychophysiological Research DOI: 10.1111/j.1469-8986.2011.01330.x 462