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Abstract

The aim of this study was to investigate whether it was possible to reduce the time taken to complete a 4000-m cycling time trial by misleading participants into believing they were racing against a previous trial, when, in fact, the power output was 2% greater. Nine trained male cyclists each completed four 4000-m time trials. The first trial was a habituation and the data from the second trial was used to form a baseline (BL). During trials 3 and 4, participants raced against an avatar, which they were informed represented their BL performance. However, whereas one of these trials was an accurate (ACC) representation of BL, the power output in the other trial was set at 102% of BL and formed the deception condition (DEC). Oxygen uptake and RER were measured continuously and used to determine aerobic and anaerobic contributions to power output. There was a significant difference between trials for time to completion (F = 15.3, P = 0.00). Participants completed DEC more quickly than BL (90% CI = 2.1-10.1 s) and ACC (90% CI = 1.5-5.4 s) and completed ACC more quickly than BL (90% CI = 0.5-4.8 s). The difference in performance between DEC and ACC was attributable to a greater anaerobic contribution to power output at 90% of the total distance (F = 5.3, P = 0.02, 90% CI = 4-37 W). The provision of surreptitiously augmented feedback derived from a previous performance reduces time taken for cyclists to accomplish a time trial of known duration. This suggests that cyclists operate with a metabolic reserve even during maximal time trials and that this reserve can be accessed after deception.

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... However, they found that pacing and perceived exertion can be influenced by interacting with the ghost. In 2012, two other similar studies using the same CompuTrainer 3D Software were conducted, but they were no longer looking into time trial effects [43,44]. Research by [43] focused on deception effects on competing with enhanced self-ghost performance with 2% extra power output. ...
... In 2012, two other similar studies using the same CompuTrainer 3D Software were conducted, but they were no longer looking into time trial effects [43,44]. Research by [43] focused on deception effects on competing with enhanced self-ghost performance with 2% extra power output. The findings showed that the enhanced self-ghost performance can make players perform at a faster speed compared to competing against a normal self-ghost performance or a baseline stage (solitary play). ...
... In 2017, another exclusively developed VR cycling exergame intervention was used by [48] to design a gamified self-competition VR exergame for people who struggle to improve or maintain exercise using a High Intensity Interval Training (HIIT) exercise protocol. A concept of feedforward (as discussed in the next subsection) was introduced, which was described as having the same effects as in previous research [41,43]. However, compared to the previous research that boosted their ghost [41,43], this intervention gave a certain amount of resistance to the player instead: to compete against their single-ghost representing their best past performance without any boosts in power or speed. ...
Article
Competing against others with better performances can demotivate and reduce players’ performances in Virtual Reality (VR) exergames. Due to this concern, previous studies have found a better solution to this which involves a system of players against themselves in VR exergames. However, the milestone of self-competition in VR exergames has not yet been compiled, compared, and discussed, as there is still room for future improvements. Therefore, this article discusses the evolution of self-competition in VR exergames, and highlights the state of the art for future studies. Related papers were gathered through keyword search strings, handpicking, and snowballing methods. Studies on self-competition in VR exergames have begun since 2007. Two categories of self-competition have been identified and suggested, which are “leaderboard” and “ghost”. The “ghost” category of self-competition is better than the “leaderboard” self-competition category in terms of enjoyment and motivation. Among the “ghost” self-competition studies, there have been implementations of a physiological technique called feedforward that has better significant results. The feedforward technique has a promising contribution towards society, especially for sedentary, less fit, and less competitive individuals.
... In reality, the pacer was programmed with a MPO which was +2% greater. [5][6][7][8] Interestingly, performance improvements in a negative performance deception trial, may also be retained in a subsequent TT once deception is revealed. 6,8 These improvements are believed to be the result of athletes accessing their reserve capacities, likely the product of a greater anaerobic energy contribution in later stages of a trial. ...
... [5][6][7][8] Interestingly, performance improvements in a negative performance deception trial, may also be retained in a subsequent TT once deception is revealed. 6,8 These improvements are believed to be the result of athletes accessing their reserve capacities, likely the product of a greater anaerobic energy contribution in later stages of a trial. 8 Environmental deception is designed to change athletes task expectations in an attempt to change their pacing approach. ...
... 6,8 These improvements are believed to be the result of athletes accessing their reserve capacities, likely the product of a greater anaerobic energy contribution in later stages of a trial. 8 Environmental deception is designed to change athletes task expectations in an attempt to change their pacing approach. A challenge for researchers providing deceptive environmental information is whether the deception is subtle enough to be effective. ...
Article
Purpose: Determine if a series of trials with fraction of inspired oxygen (FiO2) content deception could improve 4000-m cycling time-trial (TT) performance. Methods: Fifteen trained male cyclists (mean ± SD: body mass 74.2 ± 8.0 kg; peak oxygen uptake 62 ± 6 mL.kg-1.min-1) completed six, 4000-m cycling TTs in a semi-randomised order. After a familiarisation TT, cyclists were informed in two initial trials they were inspiring normoxic air (NORM, FiO2: 0.21), however in one trial (deception condition) they inspired hyperoxic air (NORM-DEC, FiO2: 0.36). During two subsequent TTs, cyclists were informed they were inspiring hyperoxic air (HYPER, FiO2: 0.36), but in one trial normoxic air was inspired (HYPER-DEC). In the final TT (NORM-INFORM) the deception was revealed, and cyclists were asked to reproduce their best TT performance while inspiring normoxic air. Results: Greater power output and faster performances occurred when cyclists inspired hyperoxic air in both truthful (HYPER) and deceptive (NORM-DEC) trials compared to NORM (P < 0.001). However, performance only improved in NORM-INFORM (377 W [95% CI 325, 429]) vs NORM (352 W [299, 404]), P < 0.001) when participants (n = 4) completed the trials in the following order: NORM-DEC, NORM, HYPER-DEC, HYPER. Conclusions: Cycling performance improved with acute exposure to hyperoxia. Mechanisms for the improvement were likely physiological, however improvement in a deception trial suggests an additional placebo effect may be present. Finally, a particular sequence of oxygen deception trials may have built psycho-physiological belief in cyclists such that performance improved in a subsequent normoxic trial.
... In comparison to exercising alone, cycling time-trial (TT) performance is improved when exercising in the presence of a competitor (Triplett, 1898) and a virtual avatar competitor that represents a previous performance (Corbett et al., 2012;Stone et al., 2012). In addition, deceptively faster avatars as a motivational stimulus have resulted in increased performances (Stone et al., 2012;Williams et al., 2015a,b;Jones et al., 2016a,b). ...
... In comparison to exercising alone, cycling time-trial (TT) performance is improved when exercising in the presence of a competitor (Triplett, 1898) and a virtual avatar competitor that represents a previous performance (Corbett et al., 2012;Stone et al., 2012). In addition, deceptively faster avatars as a motivational stimulus have resulted in increased performances (Stone et al., 2012;Williams et al., 2015a,b;Jones et al., 2016a,b). Furthermore, unsustainable behavior (i.e., a fast start) of avatar competitors has enticed participants to change their pacing strategy (Konings et al., 2016). ...
... This means that, even for those who exhibit high ego orientations, the goal of each TT is self-improvement, which presumably diminished the importance of ego goals and appealed to the participant's goals of task mastery and improvement (Reinboth and Duda, 2016). In fact, as evidence of this, there was no significant end spurt in the 1v1 or GRP sessions as participants did not increase power output to beat a competitor, although this has been demonstrated previously with competition (Corbett et al., 2012;Stone et al., 2012). Given the task involving scenario, it is surprising that there was a correlation for the SUP participants in the GRP TT (Figure 4A SUP ), with those with greater task orientations having reductions in performance. ...
Article
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Introduction: The aim of this study was to investigate time-trial (TT) performance in the presence of one competitor and in a group with competitors of various abilities. Methods: In a randomized order, 24 participants performed a 5-km cycling TT individually (IND), with one similarly matched participant (1v1), and in a group of four participants (GRP). For the GRP session, two pairs of matched participants from the 1v1 session were used. Pairs were selected so that TT duration was considered either inferior (INF) or superior (SUP) compared to the other pair of participants. Results: Overall, TT duration (P = 0.86, ηp2 < 0.01) was not different between conditions, whilst heart rate (HR) was significantly greater in GRP compared to IND (P < 0.01, ηp2 = 0.16). For INF, a large effect size for both mean power (P = 0.07, ηp2 = 0.15) and HR (P = 0.05, ηp2 = 0.16), indicates greatest effort in GRP. Pacing behaviour was affected by competition but similar in 1v1 and GRP for SUP, whilst large effect sizes indicate an increased power output in the initial 750-m for INF in GRP. Additionally, for INF, there was a significant correlation with ego orientation for an increase in TT duration between the GRP session and both the IND (r = 0.43, P = 0.04) and 1v1 (r = 0.54, P = 0.01) sessions. Conclusion: For INF participants, intensity was increased when competing in GRP. Yet, the presence of the SUP competitors resulted in lesser performance improvements for ego oriented INF participants. These findings demonstrate that consideration should be given to the ability of competitors in a group setting to provide adequate motivation.
... Previous literature investigating self-paced cycling has shown that performance is improved when receiving accurate feedback, or racing against a virtual avatar of a previous best performance (21,22). Furthermore, Stone, Thomas (23) showed that when the speed of an avatar is surreptitiously increased by 2% (a "deception" trial), participants were able to improve cycling TT performance even further. Based on these findings, it could be suggested that the presence of an avatar increases motivation via an ego-orientated goal of beating the competition (24), which may enable athletes to tolerate a greater disruption to A C C E P T E D homeostasis, and the improved performance observed in these previous studies might have been associated with a higher-than-usual magnitude of neuromuscular fatigue. ...
... During the deception trial greater motor unit recruitment of the quadriceps (increased electromyographic activity; rmsEMG) was also evident. These increases in rmsEMG have been previously suggested to have some association with the extent of anaerobic metabolism (28), which lends some support to the idea that deceiving participants could enable access to a previously protected metabolic reserve (23). Although reductions in voluntary force and voluntary activation were augmented with deceptive feedback, the involuntary twitch response to stimulation was not different between trials, indicating that a critical threshold of peripheral fatigue was not exceeded and a contractile reserve of the quadriceps was not utilized. ...
... The 2% margin of increase was specifically chosen as it is the smallest worthwhile change in 4 km performance (29), thus providing the least chance of being detected by the participant. Provision of augmented feedback equating to a 2% increase in power output has previously been successfully used to elicit performance improvements in well-trained cyclists performing similar TTs in our laboratory (23,27). It was confirmed that participants believed A C C E P T E D they were racing their baseline performance in both experimental trials and none suspected the deception at any point throughout the study. ...
Article
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Purpose: To investigate the effects of feedback, in the form of a virtual avatar paced at 100 and 102% of baseline performance, on neuromuscular fatigue following a 4 km cycling time trial (TT). We hypothesised that improved cycling performance would occur due to participants exceeding a previously established critical threshold, and experiencing greater neuromuscular fatigue. Methods: Following familiarisation, ten well-trained cyclists performed a baseline 4 km TT without feedback (BASE), followed by two, 4 km TT where they raced against an avatar (set at 100% [accurate - ACC] and 102% [deception - DEC] of baseline power output), in a randomised and counterbalanced order. Before and after each TT, neuromuscular fatigue was assessed using maximal isometric voluntary contractions (MVC) of the quadriceps, and supramaximal electrical stimulation of the femoral nerve, during and 2 s after MVCs to assess voluntary activation and potentiated twitch force. Blood lactate was taken pre- and post-trials and rating of perceived exertion (RPE) was taken throughout each TT. Results: TT performance improved following deception of feedback compared to baseline performance (-5.8 s, P = 0.019). Blood lactate increased following DEC compared to BASE (+1.37 mmol[middle dot]L-1, P = 0.019). Despite this, there was no difference in any measures of exercise-induced neuromuscular fatigue (P > 0.05). Similarly, RPE was not different between trials. Conclusion: Well-trained male cyclists can improve cycling TT performance when competing against an avatar increased to 102% of a previously established best effort. However, this improvement is not associated with a measurable augmentation of neuromuscular fatigue.
... Thus the significance and implications of identifying a plateau in 2 is apparent, manifestation of such a response represents the primary criteria in establishing a 2max has been achieved. During exercise which is classed as 'closed-loop' in design it is recognised that the individual will adopt a pacing strategy in order to optimise performance as a means of maximising substrate metabolism and compensating for the artefacts of fatigue (Stone et al 2012. A proposed model (St Clair Gibson et al., 2006;Stone et al., 2012;Tucker, 2009) reflecting pace (exercise intensity) is implemented through efferent homeostatic-orientated responses is modulated through afferent feedback systems which are both physiological and psychological in nature. ...
... During exercise which is classed as 'closed-loop' in design it is recognised that the individual will adopt a pacing strategy in order to optimise performance as a means of maximising substrate metabolism and compensating for the artefacts of fatigue (Stone et al 2012. A proposed model (St Clair Gibson et al., 2006;Stone et al., 2012;Tucker, 2009) reflecting pace (exercise intensity) is implemented through efferent homeostatic-orientated responses is modulated through afferent feedback systems which are both physiological and psychological in nature. The modulation in pace is thus a product of a perceptually mediated algorithm which is continually compared to a sub-conscious template derived from exposure to previous exercise challenges. ...
... Thus it is proposed for the current study, that when the feedback loop is disrupted in the presence of the noncontingent feedback, a 'threat' is presented to the schema which invokes a preservation of the finite anaerobic capacity, as reflected by both the increased ∆ O V  2 during the final 60s of the incremental test when compared to a baseline criterion value and the decreased sub-maximal ∆ O V  2 response from exercise onset to GET. Under these conditions the provision of the non-contingent feedback renders the exercise challenge 'open-looped' as the clarification of the end-point is now less clear in the context of the pacing schema (Foster et al., 2004, Stone et al., 2012. ...
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Results: A significant difference was observed for Δ V̇O2 over the final two consecutive 30s sampling periods between HR-A, both HR-L and HR-H (p = 0.049) and for the incidence of plateau response between condition (p = 0.021). An additional significant difference was observed for sub-maximal Δ V̇O2 responses between HR-A and HR-H (p = 0.049) and HR-A and HR-L (p = 0.006). Non-significant differences were observed for all other criteria. These data indicate that when presented with non-contingent feedback in the form of HR, that the perceptually orientated pacing schema becomes disrupted promoting a sparing of the finite anaerobic capacity to compensate for the imbalance between the afferent signal and perception of effort.
... Manipulating an athlete's feedback could therefore distort the amount of effort they are able to attribute to an exercise challenge, and ultimately affect performance. We have previously shown that it was indeed possible to reduce the amount of time taken to complete a 4000 m cycling TT by misleading participants into believing they were exercising at the same intensity as in a previous trial, when in fact the power output was 2% greater [6]. Several other researchers have conducted similar experiments examining the effects of deception during endurance exercise performance [4,[7][8][9][10]. ...
... For example, the duration of the exercise bout varies and therefore the proportion and distribution of the anaerobic and aerobic energy contribution will be different. In addition, whilst two studies investigated the effects of deception on self-paced TT performance [4,7], another two reported changes in time to volitional exhaustion during cycling at a constant power output [8,9]; and the nature of deception has ranged from manipulation of clock calibration [8], false speed feedback [7], knowledge of exercise intensity [9] and inaccurate comparative feedback on whether participants are winning or losing, compared to their baseline trial [6]. Finally some of these studies have been limited by small sample sizes [6,9,10], the use of untrained participants [8,9] and the use of exercise tests which have been shown to have low test-retest reliability [8,9]. ...
... In addition, whilst two studies investigated the effects of deception on self-paced TT performance [4,7], another two reported changes in time to volitional exhaustion during cycling at a constant power output [8,9]; and the nature of deception has ranged from manipulation of clock calibration [8], false speed feedback [7], knowledge of exercise intensity [9] and inaccurate comparative feedback on whether participants are winning or losing, compared to their baseline trial [6]. Finally some of these studies have been limited by small sample sizes [6,9,10], the use of untrained participants [8,9] and the use of exercise tests which have been shown to have low test-retest reliability [8,9]. ...
Article
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Purpose The aim of the present study was to investigate whether a magnitude of deception of 5% in power output would lead to a greater reduction in the amount of time taken for participants to complete a 4000 m cycling TT than a magnitude of deception of 2% in power output, which we have previously shown can lead to a small change in 4000 m cycling TT performance. Methods Ten trained male cyclists completed four, 4000 m cycling TTs. The first served as a habituation and the second as a baseline for future trials. During trials three and four participants raced against a pacer which was set, in a randomized order, at a mean power output equal to 2% (+2% TT) or 5% (+5% TT) higher than their baseline performance. However participants were misled into believing that the power output of the pacer was an accurate representation of their baseline performance on both occasions. Cardiorespiratory responses were recorded throughout each TT, and used to estimate energy contribution from aerobic and anaerobic metabolism. Results Participants were able to finish the +2% TT in a significantly shorter duration than at baseline (p = 0.01), with the difference in performance likely attributable to a greater anaerobic contribution to total power output (p = 0.06). There was no difference in performance between the +5% TT and +2% TT or baseline trials. Conclusions Results suggest that a performance reserve is conserved, involving anaerobic energy contribution, which can be utilised given a belief that the exercise will be sustainable however there is an upper limit to how much deception can be tolerated. These findings have implications for performance enhancement in athletes and for our understanding of the nature of fatigue during high-intensity exercise.
... More specifically, Taylor and Smith (2014) have demonstrated that run performance during sprintdistance triathlon may be enhanced by the imposition of a deceptively aggressive starting strategy (3% faster than baseline performance), when compared to more conservative approaches to initial pace deception (3% slower than, and equal to, baseline performance). These findings would appear to support the view that individual's typically maintain some form of reserve capacity during self-paced exercise and perform at a relative intensity somewhat below their task-specific maximum capacity, even when their intention is to optimize performance (Stone et al., 2012;St Clair Gibson et al., 2013). Furthermore, this study adds weight to the idea that an individual's expectations, beliefs and perceptions play an important role in how much reserve capacity they are willing to utilize during self-paced multi-modal exercise tasks. ...
... As highlighted by these authors, such differences cannot be ignored given that an average of only 9 s can separate the run and overall event ranking positions for of the top 20 sprint-distance triathletes at (age-group) World Championship level (ITU, 2012). The current study findings therefore extend those of previous deception research to offer further evidence that expectations and beliefs regarding a particular exercise task and/or intervention are likely to influence athletes' perception of internal and external stimuli, and the subsequent conscious (anticipatory) pacing decisions they make in attempting to optimize performance (Micklewright et al., 2010;Stone et al., 2012;Taylor and Smith, 2014;Williams et al., 2014Williams et al., , 2015Waldron et al., 2015;Shei et al., 2016). It has been speculated that this is the case during multi-modal exercise (Hausswirth et al., 1999), with previous simulated triathlon studies finding that a relatively aggressive mid-event (i.e., cycling) pacing strategy leads to subsequent reductions in running performance (Hausswirth et al., 1999;Suriano and Bishop, 2010). ...
... Given these points, it is appears likely that an array of psychophysiological factors may indeed influence pacing decisions during exercise, possibly by way of "fine-tuning" the "coarse" relationship between RPE growth and momentary power output (Cohen et al., 2013). This suggestion is not unique, with a growing number of contemporary pacing studies theorizing that perceptions other than RPE (e.g., sense of effort, perceived muscular pain, breathlessness, thermal strain, and affect) are of equal, if not greater, importance to anticipatory pace regulation and reserve capacity maintenance (Micklewright et al., 2010;Renfree et al., 2012;Stone et al., 2012;Jones et al., 2014;Pageaux, 2014;Williams et al., 2014Williams et al., , 2015. In particular, an individual's affective status has been suggested as a potentially more influential mediator of pace regulation than RPE (Baron et al., 2011;Jones et al., 2014;Renfree et al., 2014). ...
Article
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Purpose: To examine the effects of deceptively aggressive bike pacing on performance, pacing, and associated physiological and perceptual responses during simulated sprint-distance triathlon. Methods: Ten non-elite, competitive male triathletes completed three simulated sprint-distance triathlons (0.75 km swim, 500 kJ bike, 5 km run), the first of which established personal best “baseline” performance (BL). During the remaining two trials athletes maintained a cycling power output 5% greater than BL, before completing the run as quickly as possible. However, participants were informed of this aggressive cycling strategy before and during only one of the two trials (HON). Prior to the alternate trial (DEC), participants were misinformed that cycling power output would equal that of BL, with on-screen feedback manipulated to reinforce this deception. Results: Compared to BL, a significantly faster run performance was observed following DEC cycling (p < 0.05) but not following HON cycling (1348 ± 140 vs. 1333 ± 129 s and 1350 ± 135 s, for BL, DEC, and HON, respectively). As such, magnitude-based inferences suggest HON running was more likely to be slower, than faster, compared to BL, and that DEC running was probably faster than both BL and HON. Despite a trend for overall triathlon performance to be quicker during DEC (4339 ± 395 s) compared to HON (4356 ± 384 s), the only significant and almost certainly meaningful differences were between each of these trials and BL (4465 ± 420 s; p < 0.05). Generally, physiological and perceptual strain increased with higher cycling intensities, with little, if any, substantial difference in physiological and perceptual response during each triathlon run. Conclusions: The present study is the first to show that mid-event pace deception can have a practically meaningful effect on multi-modal endurance performance, though the relative importance of different psychophysiological and emotional responses remains unclear. Whilst our findings support the view that some form of anticipatory “template” may be used by athletes to interpret levels of psychophysiological and emotional strain, and regulate exercise intensity accordingly, they would also suggest that individual constructs such as RPE and affect may be more loosely tied with pacing than previously suggested.
... In recent years, a number of studies have shown that physiological, psychological and environmental factors can affect overall performance and pacing ). These factors include oxygen availability (Amann et al., 2006;Clark et al., 2007;Tucker et al., 2007;Périard and Racinais, 2016), heat-stress (Peiffer and Abbiss, 2011), wind velocity (Teunissen et al., 2013), hydration status (Dugas et al., 2009), carbohydrate and caffeine ingestion (Wiles et al., 2006), pre-cooling strategies (Duffield et al., 2010), motivation , fatigue (Skorski et al., 2015), deception (Stone et al., 2012;Jones et al., 2016b;Shei et al., 2016), pacing feedback (Thompson et al., 2003(Thompson et al., , 2004 and music . However, on the basis of existing studies it is still difficult to arrive at an overall conclusion as to whether these manipulations have a negative or positive effect on pacing and performance, and indeed which part of the pacing strategy changes (start, middle and end) during trials. ...
... The variability of power output was relatively low in these trials which might suggest the change in power output, caused by the deception, was sufficient to improve performance but not so great as to be intolerable. Previous work by Stone et al. (2012) found when participants were deceived of a 2% increase in the MPO they demonstrated a greater anaerobic energy contribution at 90% of a 4000-m time-trial and a concomitant significant improvement in power output. The meta-analysis did not find an improvement for the end section of trials, however this might be because trials were segmented into thirds rather than 10% bins as in the Stone et al. (2012) study. ...
... Previous work by Stone et al. (2012) found when participants were deceived of a 2% increase in the MPO they demonstrated a greater anaerobic energy contribution at 90% of a 4000-m time-trial and a concomitant significant improvement in power output. The meta-analysis did not find an improvement for the end section of trials, however this might be because trials were segmented into thirds rather than 10% bins as in the Stone et al. (2012) study. The meta-analysis also demonstrated informed feedback (Figure 11; where participants completed a time-trial subsequent to being informed the MPO of a pacer in their previous trial was set to a greater exercise intensity than their baseline performance) led to improved trial performance compared to an original (baseline) time-trial. ...
Article
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In search of their optimal performance athletes will alter their pacing strategy according to intrinsic and extrinsic physiological, psychological and environmental factors. However, the effect of some of these variables on pacing and exercise performance remains somewhat unclear. Therefore, the aim of this meta-analysis was to provide an overview as to how manipulation of different extrinsic factors affects pacing strategy and exercise performance. Only self-paced exercise studies that provided control and intervention group(s), reported trial variance for power output, disclosed the type of feedback received or withheld, and where time-trial power output data could be segmented into start, middle and end sections; were included in the meta-analysis. Studies with similar themes were grouped together to determine the mean difference (MD) with 95% confidence intervals (CIs) between control and intervention trials for: hypoxia, hyperoxia, heat-stress, pre-cooling and various forms of feedback. A total of 26 studies with cycling as the exercise modality were included in the meta-analysis. Of these, four studies manipulated oxygen availability, eleven manipulated heat-stress, four implemented pre-cooling interventions and seven studies manipulated various forms of feedback. Mean power output (MPO) was significantly reduced in the middle and end sections (p < 0.05), but not the start section of hypoxia and heat-stress trials compared to the control trials. In contrast, there was no significant change in trial or section MPO for hyperoxic or pre-cooling conditions compared to the control condition (p > 0.05). Negative feedback improved overall trial MPO and MPO in the middle section of trials (p < 0.05), while informed feedback improved overall trial MPO (p < 0.05). However, positive, neutral and no feedback had no significant effect on overall trial or section MPO (p > 0.05). The available data suggests exercise regulation in hypoxia and heat-stress is delayed in the start section of trials, before significant reductions in MPO occur in the middle and end of the trial. Additionally, negative feedback involving performance deception may afford an upward shift in MPO in the middle section of the trial improving overall performance. Finally, performance improvements can be retained when participants are informed of the deception.
... Challenge and threat states have also been shown to influence cognitive processes as well as behavior, where an individual's motivation may be focussed on success in a challenge state and on the prevention of failure in a threat state (Blascovich et al., 2004). These positive and negative motivational states have been found to influence effort, emotions, decision-making, efficacious appraisals and physiological responses (Skinner and Brewer, 2002;Meijen et al., 2013;Vine et al., 2013) and could therefore explain previous findings of altered perceptual responses, such as RPE and affect, in deceptive conditions (Stone et al., 2012;Jones et al., 2016). In the previously mentioned study by Jones et al. (2016), the deception group experienced more negative affect and higher perceived exertion than the control group which supports these aforementioned patterns within threat states. ...
... What Shei et al. (2016) did not acknowledge however, is that the mere presence of the avatar in both TTs was likely to have had a motivational influence and could alone explain the faster performances (Williams et al., 2014(Williams et al., , 2015Jones et al., 2016). The lack of a control group and the use of a static avatar set as a depiction of the average baseline power output further limits the study, as indeed it also does in some other deception research (Stone et al., 2012). ...
... Even with corrected knowledge of the prior deception, the DEC group's perceptual responses nor performance differed in their SUB TT. The current study supported previous findings which evidenced acute facilitative effects of visual feedback provision on performance during self-paced cycling TTs (Corbett et al., 2012;Stone et al., 2012;Williams et al., 2014Williams et al., , 2015Jones et al., 2016). Both groups performed against the same magnitude of pacer (102% of FBL) but were provided with different instructions and therefore had different pre-performance beliefs. ...
Article
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The provision of performance-related feedback during exercise is acknowledged as an influential external cue used to inform pacing decisions. The provision of this feedback in a challenging or deceptive context allows research to explore how feedback can be used to improve performance and influence perceptual responses. However, the effects of deception on both acute and residual responses have yet to be explored, despite potential application for performance enhancement. Therefore, this study investigated the effects of challenging and deceptive feedback on perceptual responses and performance in self-paced cycling time trials (TT) and explored whether changes in performance are sustained in a subsequent TT following the disclosure of the deception. Seventeen trained male cyclists were assigned to either an accurate or deceptive feedback group and performed four 16.1 km cycling TTs; 1 and 2) ride-alone baseline TTs where a fastest baseline (FBL) performance was identified, 3) a TT against a virtual avatar representing 102% of their FBL performance (PACER), and 4) a subsequent ride-alone TT (SUB). The deception group, however, were initially informed that the avatar accurately represented their FBL, but prior to SUB were correctly informed of the nature of the avatar. Affect, self-efficacy and RPE were measured every quartile. Both groups performed PACER faster than FBL and SUB (p < 0.05) and experienced lower affect (p = 0.016), lower self-efficacy (p = 0.011), and higher RPE (p < 0.001) in PACER than FBL. No significant differences were found between FBL and SUB for any variable. The presence of the pacer rather than the manipulation of performance beliefs acutely facilitates TT performance and perceptual responses. Revealing that athletes’ performance beliefs were falsely negative due to deceptive feedback provision has no effect on subsequent perceptions or performance. A single experiential exposure may not be sufficient to produce meaningful changes in the performance beliefs of trained individuals beyond the acute setting.
... Proposed mechanisms 38 for these improvements have predominantly focused on arousal, motivation and affect 39 (Brehm and Self, 1989; Renfree et al., 2014). Recently, a number of groups have reported 40 improved exercise performance when the speed of the observed model was deceptively 41 increased (Corbett et al., 2012; Stone et al., 2012; Williams et al., 2015). These findings 42 suggest that the effect of competition on exercise performance may be influenced by the 43 speed of the competitor. ...
... The first aim was to examine the effect of observation of a fast exercise on upper-body arm- 86 crank exercise performance (Experiment 1 and 2). We predicted that observation of a fast 87 exercise would improve exercise performance, replicating effects seen in lower-body exercise 88 (Corbett et al., 2012; Stone et al., 2012). However, in contrast to these previous studies, we 89 used a stationary model for observation to control for the possibly confounding influence of 90 changes in optic flow on exercise performance (Parry et al., 2012). ...
... There was an effect of Video The main finding of Experiment 1 was that observation of a fast exercise improved arm-crank 182 time trial performance compared to observation of the no video condition, whilst observation 183 of typical speed exercise did not influence performance replicating previously reported 184 effects in in lower body exercise (Corbett et al. 2012; Stone et al. 2012). This result suggests 185 the observation effect on performance cannot only be attributed to optical flow. ...
Article
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Purpose: Observation of a model performing fast exercise improves simultaneous exercise performance; however, the precise mechanism underpinning this effect is unknown. The aim of the present study was to investigate whether the speed of the observed exercise influenced both upper body exercise performance and the activation of a cortical action observation network (AON). Method: In Experiment 1, 10 participants completed a 5 km time trial on an arm-crank ergometer whilst observing a blank screen (no-video) and a model performing exercise at both a typical (i.e., individual mean cadence during baseline time trial) and 15% faster than typical speed. In Experiment 2, 11 participants performed arm crank exercise whilst observing exercise at typical speed, 15% slower and 15% faster than typical speed. In Experiment 3, 11 participants observed the typical, slow and fast exercise, and a no-video, whilst corticospinal excitability was assessed using transcranial magnetic stimulation. Results: In Experiment 1, performance time decreased and mean power increased, during observation of the fast exercise compared to the no-video condition. In Experiment 2, cadence and power increased during observation of the fast exercise compared to the typical speed exercise but there was no effect of observation of slow exercise on exercise behavior. In Experiment 3, observation of exercise increased corticospinal excitability; however, there was no difference between the exercise speeds. Conclusion: Observation of fast exercise improves simultaneous upper-body exercise performance. However, because there was no effect of exercise speed on corticospinal excitability, these results suggest that these improvements are not solely due to changes in the activity of the AON.
... The CGM theorizes that a feed-forward process attempts to elicit optimal exercise performance while ensuring that a catastrophic physiological failure is avoided by maintaining a reserve capacity. Gaining access to this reserve capacity however, may allow for greater exercise performance [27]. Providing deceptively augmented feedback may be one avenue to achieve this performance enhancement [27]. ...
... Gaining access to this reserve capacity however, may allow for greater exercise performance [27]. Providing deceptively augmented feedback may be one avenue to achieve this performance enhancement [27]. Improving performance by increasing the utilization of any metabolic reserve has been achieved through various forms of deception [15]. ...
... Improving performance by increasing the utilization of any metabolic reserve has been achieved through various forms of deception [15]. For example, cycling time trials involving deceptively altered feedback have been found to result in shorter time to completion [5,27], higher power output [23] and a larger observed end-spurt ...
Article
We investigated whether performance gains achieved with deception persisted after the deception was revealed, and whether pacing strategy changed. 14 trained cyclists completed 4 simulated 4-km time trials (TT) on a cycle ergometer comprising familiarization and baseline trials (BAS), followed by "unaware" (of deception, UAW) and "aware" (of deception, AW) trials on separate days. In the UAW trial, participants competed against an on-screen avatar set at 102% of their baseline trial mean power output (Pmean) believing it was set at 100% of BAS Pmean. 24 h prior to the AW trial, participants were informed of the deception in the UAW trial. 4 participants did not improve in the UAW trial compared to BAS. 10 participants improved time to completion (TTC) and Pmean in the UAW and AW trials compared to BAS (p<0.03) with no significant differences between UAW and AW (p=1.0). Pacing strategy (at 0.5-km intervals) and RPE responses were unchanged (p>0.05) for these participants. In summary, deception did not improve performance in all participants. However, participants whose time trial performance improved following deception could retain their performance gains once the deception was revealed, demonstrating a similar pacing strategy and RPE response. © Georg Thieme Verlag KG Stuttgart · New York.
... Recently, interrelationships between central and peripheral factors of fatigue during SIT have been investigated (Amann, Sidhu, Weavil, Mangum, & Venturelli, 2015;Stone, et al., 2012;Swart, et al., 2009). Tucker (2009) proposed an association between the development of peripheral fatigue and central motor drive through alterations in afferent neural feedback from the myofibrils to the central nervous system (CNS). ...
... Considering the present investigation employed less recovery and more sprints, it is likely that a large portion of energy demand was met by oxidative metabolism. Regardless of the exact mechanism, the findings of the present investigation add to the increasing body of evidence (Amann & Dempsey, 2008;Noakes, 2012), suggesting that human muscle fatigue does not reside solely in the muscle (Ganevia, 2001) and that the CNS regulates both the prolonged (Noakes, 2011;Stone, et al., 2012;Swart, et al., 2009), intermittent (Foster, et al., 2014) and, in the case of the present investigation, short duration (as peak power output is typically reached ~5 seconds, [Herbert, Sculthorpe, Baker, & Grace, 2015]) exercise performance. It is worthwhile noting however that our investigation concerned females, and therefore replication in males may not result in the same performance enhancement. ...
... However, it should be noted that positive effects of ACT on pain perception and performance have not always been reported, and very large doses should be avoided. Indeed, despite an abundance of evidence suggesting that depression of pain perception or peripheral feedback enhances performance (Foster, et al., 2014;Mauger, et al., 2010;Stone, et al. 2012), Amann and colleagues (2009) reported that complete blocking of lower limb afferent feedback actually reduced performance due to an overly aggressive start to a time trial and therefore a depletion of the curvature constant parameter (W'), (Skiba, Chidnok, Vanhatalo, & Jones, 2012). ...
Article
Full-text available
The aim of this study is to investigate the effect of acute acetaminophen (ACT) ingestion on eight maximal 30-second cycling bouts, interspersed with two-minute rests. Seven recreationally active females (N=7, 22.8±6.7 years of age, with a stature of 163.4±5.8 cm, and body mass of 58.9±5.9 kg) participated in a placebo-controlled, randomized crossover design. Pain perception, heart rate, and power profiles were analyzed using a time x condition repeated measures ANOVA. Blood lactate after the eighth bout and total work done were analyzed using the paired samples t-test.Participants achieved a significantly greater (p=.007, =.725) peak power output during the ACT trials (402.9±73.8 W, 95% CI=334.6–471.1 W) when compared to the placebo (PLA) trials (378.7±64.6 W, 95% CI=319.0–438.4 W). Supplementation of ACT had no effect on mean power output, blood lactate accumulation, pain perception, or total work done after eigth bouts (p>.05).Data presented here suggest females can improve peak power output during repeated Wingate tests with ACT ingestion. It is proposed that the altered afferent feedback may have caused these alterations in power output.
... 5 TT. 12 Moreover, when this feedback was manipulated to represent 102% of the athletes' fastest baseline, performance was improved further; attributed to the accessing of a reserve capacity. 12 Alternatively, this is also supported by motivational theories stating that the presence of competition, in this case a faster self, can improve performance. ...
... 5 TT. 12 Moreover, when this feedback was manipulated to represent 102% of the athletes' fastest baseline, performance was improved further; attributed to the accessing of a reserve capacity. 12 Alternatively, this is also supported by motivational theories stating that the presence of competition, in this case a faster self, can improve performance. 13 Whilst some studies have shown that performance is influenced in a trial in which the deception is employed, i.e. an acute response, others have investigated the effects of deception on subsequent performance, i.e. a residual response. ...
... 23 Participants were informed that their responses should reflect the affective or emotional components of the exercise and not the physical sensations of effort or strain. Borg's 24 [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] scale was used to measure RPE and for task-specific self-efficacy, participants reported 'how confident are you to continue at your current pace for the remaining distance of the trial?' on a percentage scale from 0% (cannot do at all) to 100% (absolutely certain can do). 25 This type of self-efficacy measurement, employed throughout the trial, was constructed to reflect the cyclists' beliefs concerning their pacing strategy selection and is a novel contribution to the field of pacing. ...
Article
Full-text available
Objectives: Feedback deception is used to explore the importance of expectations on pacing strategy and performance in self-paced exercise. The deception of feedback from a previous performance explores the importance of experience knowledge on exercise behaviour. This study aimed to explore the acute and residual effects of the deception of previous performance speed on perceptual responses and performance in cycling time trials. Design: A parallel-group design. Methods: Twenty cyclists were assigned to a control or deception group and performed 16.1 km time trials. Following a ride-alone baseline time trial (FBL), participants performed against a virtual avatar representing their FBL performance (PACER), then completed a subsequent ride-alone time trial (SUB). The avatar in the deception group, however, was unknowingly set 2% faster than their FBL. Results: Both groups performed faster in PACER than FBL and SUB (p < 0.05), but SUB was not significantly different to FBL. Affect was more negative and Ratings of Perceived Exertion (RPE) were higher in PACER than FBL in the deception group (p < 0.05). Conclusions: The presence of a visual pacer acutely facilitated time trial performance, but deceptive feedback had no additional effect on performance. The deception group did however experience more negative affect and higher RPE in PACER, whereas these responses were absent in the control group. The performance improvement was not sustained in SUB, suggesting no residual performance effects occurred.
... The CGM theorizes that a feed-forward process attempts to elicit optimal exercise performance while ensuring that a catastrophic physiological failure is avoided by maintaining a reserve capacity. Gaining access to this reserve capacity however, may allow for greater exercise performance [27]. Providing deceptively augmented feedback may be one avenue to achieve this performance enhancement [27]. ...
... Gaining access to this reserve capacity however, may allow for greater exercise performance [27]. Providing deceptively augmented feedback may be one avenue to achieve this performance enhancement [27]. Improving performance by increasing the utilization of any metabolic reserve has been achieved through various forms of deception [15]. ...
... Improving performance by increasing the utilization of any metabolic reserve has been achieved through various forms of deception [15]. For example, cycling time trials involving deceptively altered feedback have been found to result in shorter time to completion [5,27], higher power output [23] and a larger observed end-spurt ...
Conference Paper
Purpose: The aim of the present study was to investigate whether performance gains achieved with deception persist after the deception was revealed, and to assess whether pacing strategy was altered following knowledge of deception. Methods: Fourteen trained competitive cyclists completed four simulated 4-km cycling time trials on a cycle ergometer comprising of a familiarization trial, baseline trial (BAS), deception trial (DEC), and knowledge of deception trial (KDE) on separate occasions. In the DEC and KDE trials, subjects competed against an on-screen avatar set to 102% of their baseline mean power output (Pmean). Pacing strategy was characterized by calculating the Pmean for each 0.5-km segment of the distance covered. Results: Ten subjects completed the DEC trial faster compared to BAS trial (p = 0.001) and the KDE trial faster compared to the BAS trial (p = 0.024, 95% CI = -15.5 to -1.1s), but not compared to DEC (p = 1.0, 95% CI = -3.3 to 4.3s). The four subjects who did not improve in the DEC trial completed the KDE trial faster than the DEC trial (p = 0.009, 95% CI = -17.5 to -5.3s), but not the BAS trial (p = 0.421, 95% CI = -6.3 to 15.0 s). Pacing strategy was unchanged (p>0.05) for all subjects, whether or not they improved in the DEC trial. Differences in ratings of perceived exertion were not observed (p>0.05) for either group for any trial. Conclusion: Trained cyclists whose time trial performance improves following deception retain their performance gains once the deception is revealed and adopt a similar pacing strategy in both of the improved trials (DEC and KDE). This suggests that the experience gained during the DEC trial facilitates improved performance during a subsequent trial with the same pacing strategy and RPE score.
... Although avatar research involving deception with well-trained cyclists has consistently yielded performance improvements, the pacing strategies differ across studies (Konings & Hettinga, 2018b). Some work has observed a subtle upward shift in power output throughout the entire exercise bout (Shei, Thompson, Chapman, Raglin, & Mickleborough, 2016), whereas others have found an increase in power output during the final third of a 4 km time trial (Stone et al., 2012). Deception also typically results in increases in perceived effort and physiological indicators of strain (Konings & Hettinga, 2018b). ...
... The presence of an opponent appears to be a crucial factor impacting athletic decision-making, particularly in the initial stages of a race where the influences of competitors were of a comparable level, leading to a faster start (Konings et al., 2016). While it has been proposed that it is the presence of the avatar alone that facilitates improvements in performance and alters perceptual responses (Jones et al., 2016), some research has found that the magnitude of improvement using a deceptive manipulation is greater than when competing against a non-manipulated avatar (Shei et al., 2016;Stone et al., 2012). Still others have found that a non-manipulated avatar does not change performance (Ansdell et al., 2018). ...
... But RPE and real physiological constraints can be dissociated from each other under certain conditions (Hardy & Rejeski, 1989). For example, deception or altered feedback on remaining time increases RPE without changing exercise intensity (Baden, McLean, Tucker, Noakes, & St Clair, 2005;Jones et al., 2013;Morton, 2009;Stone et al., 2012). The increasing rate of RPE is known to accelerate time to exhaustion and decrease performance. ...
... But it was already shown that RPE could be positively or negatively influenced by pharmacological (Mauger, Jones, & Williams, 2010;Roelands & Meeusen, 2010;Sgherza et al., 2002;Watson et al., 2005) or psychological manipulations (Barwood, Weston, Thelwell, & Page, 2009;Morton, 2009;Williamson, McColl, Mitchell, Raven, & Morgan, 2001). For example, deception is known to increase the rate of RPE and decrease the level of performance (Stone et al., 2012;Jones et al., 2013). On the other hand, in a better motivational context, the subjects can increase their level of performance without changing RPE (Aitchison, Turner, & Ansley, 2013;Blanchfield, Hardy, de Moree, Staiano, & Marcora, 2014;Marcora et al., 2009;Wilmore, 1968). ...
Article
The purpose of this study was to analyze the pacing strategy and its affective consequences during self-paced cycling time trials (TT) performed at different severity of hypoxia. Eight competitive cyclists performed five 30 min self-paced TTs at their best performance in the following conditions: 1) normobaric normoxia (NNSL); 2) normobaric hypoxia under two simulated altitudes: 2000 m (NH2000) and 3500 m (NH3500) and 3) normobaric hypoxia but the cyclists were deceived and thought to be at sea level for 2000 m (DecNH2000) and 3500 m (DecNH3500). Power Output (PO), oxygen uptake (VO2), and blood lactate concentration ([La]) were recorded to assess exercise intensity and physiological adaptations. The rate of perceived exertion (RPE) and pleasure were measured with a CR10 Borg scale to evaluate the affective load (AL). PO and VO2 decreased with the severity of hypoxia but no significantly difference on performance was measured between deceived and real conditions, except for pacing strategy. The started intensity depends on the exercise expectations, but PO was rapidly adjusted with the physiological constraints and the rate of increase of RPE. Finally, AL did not reach maximal values so that the athletes sustained a physiological and emotional reserve to perform a final spurt.
... A reduction in blood glucose is not consistently observed with tasks of self-control [69,71], nor are reports of performance restoration with glucose or carbohydrate supplementation [71][72][73][74]. Furthermore, a model based purely on a depletable physiological resource would not explain the performance benefits obtained from psychological strategies such as motivational self-talk [75], financial incentives [76,77] and deception [78]. While these studies disprove glucose as the primary mediator of self-control, the idea that a cerebral fuel source may contribute to impaired physical performance following mental exertion cannot be disregarded completely. ...
... Although the reported 'motivation to perform' did not differ between conditions, all participants expressed a wish to 'beat the competition' [113]. Similar findings have also been observed in studies of deception [78,114,115]. These studies suggest that changes in motivation may influence the reported RPE, and further highlight that the current methods of quantifying motivation may be limited. ...
Article
Full-text available
Mental fatigue reflects a change in psychobiological state, caused by prolonged periods of demanding cognitive activity. It has been well documented that mental fatigue impairs cognitive performance; however, more recently, it has been demonstrated that endurance performance is also impaired by mental fatigue. The mechanism behind the detrimental effect of mental fatigue on endurance performance is poorly understood. Variables traditionally believed to limit endurance performance, such as heart rate, lactate accumulation and neuromuscular function, are unaffected by mental fatigue. Rather, it has been suggested that the negative impact of mental fatigue on endurance performance is primarily mediated by the greater perception of effort experienced by mentally fatigued participants. Pageaux et al. (Eur J Appl Physiol 114(5):1095–1105, 2014) first proposed that prolonged performance of a demanding cognitive task increases cerebral adenosine accumulation and that this accumulation may lead to the higher perception of effort experienced during subsequent endurance performance. This theoretical review looks at evidence to support and extend this hypothesis.
... These performance improvements with deception were attributable to a greater anaerobic contribution to total energy expenditure and were associated with a reduced perceived exertion and attentional focus towards internal sensory feedback (e.g. leg fatigue, pain, heart beating or breathing frequency and depth) (11,33,37,38). The combined increase in power output and anaerobic contribution to total energy expenditure might be linked to a higher muscle activation (i.e. ...
... Moreover, most experimental approaches using deceptive feedback were based on a competitive simulation, during which participants were instructed to race against a virtual opponent (11,33,37,38). These approaches may limit the application of deceptive feedback to training and may not be fully representative of competition at the highest level, as performance in elite cyclists or endurance runners rely significantly on pacemakers. ...
Article
Purpose: This study aimed to investigate the effect of different magnitudes of deception on performance and exercise-induced fatigue during cycling time-trial. Methods: Following three familiarization visits, three females and eight males performed three 5 km cycling time-trials while following a simulated dynamic avatar reproducing either 100% (5K100%), 102% (5K102%) or 105% (5K105%) of the subject's previous fastest trial. Quadriceps muscle activation was quantified with surface electromyography. Fatigue was quantified by pre- to post-exercise (10 s through 15 min recovery) changes in quadriceps maximal voluntary contraction (MVC) force, potentiated twitch force evoked by electrical femoral nerve stimulation (QTSingle) and voluntary activation (VA, twitch interpolation technique). Results: Greater quadriceps muscle activation in 5K102% vs. 5K100% (12±11%) was found in parallel with a 5±2% and 2±1% improvement in power output and completion time, respectively (p < 0.01). Exercise-induced reduction in MVC force and VA were 14±19% and 28±31% greater at exercise termination (at 10 s) whereas QTSingle recovery (from 10 s to 15 min) was 5±5% less in 5K102% vs. 5K100% (p < 0.01). No difference in performance or fatigue indices measured at exercise termination was found between 5K100% and 5K105%. Conclusion: Muscle activation and performance improvements during a deceptive cycling time-trial were achieved only with a 2% magnitude of deception and were associated with a further impairment in MVC force, QTSingle recovery and VA compared to control. Performance improvement during cycling time-trial with augmented deceptive feedback therefore resulted in exacerbated exercise-induced peripheral and central fatigue.
... Indeed, the presence of an opponent has been shown to influence performance (Hulleman et al., 2007;Peveler and Green, 2010;Bath et al., 2012;Corbett et al., 2012;Stone et al., 2012;Lambrick et al., 2013;Tomazini et al., 2015;Williams et al., 2015a,b;Jones et al., 2016;Konings et al., 2016c). In general, improved performance is seen during competitive running and cycling trials compared to individual or non-competitive trials (Corbett et al., 2012;Stone et al., 2012;Tomazini et al., 2015;Williams et al., 2015a,b;Konings et al., 2016c). ...
... Indeed, the presence of an opponent has been shown to influence performance (Hulleman et al., 2007;Peveler and Green, 2010;Bath et al., 2012;Corbett et al., 2012;Stone et al., 2012;Lambrick et al., 2013;Tomazini et al., 2015;Williams et al., 2015a,b;Jones et al., 2016;Konings et al., 2016c). In general, improved performance is seen during competitive running and cycling trials compared to individual or non-competitive trials (Corbett et al., 2012;Stone et al., 2012;Tomazini et al., 2015;Williams et al., 2015a,b;Konings et al., 2016c). However, the actual presence and perception of the opponent seems to be crucial. ...
Article
Full-text available
Athlete-environment interactions are crucial factors in understanding the regulation of exercise intensity in head-to-head competitions. Previously, we have proposed a framework based on the interdependence of perception and action, which allows us to explore athletic behaviour in the more complex pacing situations occurring when athletes need to respond to actions of their opponents. In the present perspective we will further explore whether opponents, crucial external factors in competitive sports, could indeed be perceived as social invitations for action. Decisions regarding how to expend energy over the race are based on internal factors such as the physiological/biomechanical capacity of the athlete in relation to external factors such as those presented by opponents. For example: Is the athlete able to overtake competitors, or not? We present several experimental studies that demonstrate that athletes regulate their exercise intensity differently in head-to-head competition compared to time-trial exercises: Relational athlete-environment aspects seem to outweigh benefits of the individual optimal energy distribution. Also, the behaviour of the opponents has been shown to influence pacing strategies of competing athletes, again demonstrating the importance of relational athlete-environment aspects in addition to strictly internal factors. An ecological perspective is presented in which opponents are proposed to present social affordances, and decision-making is conceptualized as a resultant of affordance-competition. This approach will provide novel insights in tactical decision-making and pacing behaviour in head-to-head competitions. Future research should not only focus on the athlete’s internal state, but also try to understand opponents in the context of the social affordances they provide.
... The sensitivity and upper limit of undetectable deceptive feedback with positive performance results in cyclists was a two percent increase in specified power output was required (Stone et al., 2012). This percentage was the smallest worthwhile change in performance for a timed distance trial. ...
Article
Full-text available
Deceptive feedback involves offering altered performance results to athletes with the intention of eliciting greater physical output. The use of feedback and feedforward mechanisms used to predict a performance endpoint is referred to as teleoanticipation. The interpretation of physciological and psychological effects of stimuli upon is the basis for current and future performances. The purpose of the present study was to investigate the effects of false positive feedback, of varying percentages, on maximal strength, physical self-efficacy, and strength goals through the lens of teleoanticipation. Recreational lifters (n=17) were tested for one repetition maximum (1RM) leg press scores, future goal weights (G), and physical self-efficacy (SE), over the course of two orientation sessions and five separate test sessions. A baseline of 1RM strength was established during the first test control session (TC). Deceptive feedback was given on the subsequent three sessions and consisted of loads that were 5% (T+5), 10% (T+10) or 15% (T+15) above the loads reported to participants during each session. The full extent of deception was revealed on the final session of testing (TF). There were significant differences between the trials for 1RM measures; TC was significantly different from the T+5, T+10, and TF. Results for G revealed significance for all trials compared to TC but no differences were found in self-esteem. This data suggests that deception may enhance 1 RM measures, negatively impact goal setting, but not affect physical self-efficacy.
... 3.3 Insight 3: labeling something as ''impossible'' can constitute a precious indication that the issue deserves more attention, with the potential to make a difference and make the world a better place For instance, cyclists have been tricked to enhance their performances and surpass what they considered as their limits thanks to feedback deception (Stone et al., 2012). Roger Bannister, the first athlete to break the four-minute mile, stated: "It is the brain, not the heart or lungs, that is the critical organ. ...
Article
Purpose Labeling something as “impossible” can be performative and deprive businesses from promising ideas, by activating limiting mental models and self-fulfilling prophecies. Adopting an “everything may be(come) possible” thinking as the default option can lead businesses to discover unexpected and valuable directions and make the world a better place. This paper aims to propose practical insights to harness the power of “impossible” thinking such as considering impossibility as a current and temporary state, adopting an unconventional mindset and redirecting the reflection on what is needed to make the idea possible. Falling in love with any impossible target is obviously not without downsides. Design/methodology/approach This paper discusses conceptually how adopting an impossible thinking approach can help business to discover unexpected and valuable directions. Findings The authors caution managers on the inappropriate use of the “impossible” label that can be performative, activate a limiting mental model, lead to a self-fulfilling prophecy and deprive businesses from promising ideas. This paper proposes ways by which the power of impossible thinking can be harnessed to make a difference. Research limitations/implications Discarding impossible ideas seems perfectly justified from a logical or cultural viewpoint while constituting simultaneously a bad decision from a business viewpoint. The generalization of authors’ insight must be undertaken with caution, given that harnessing the power of impossible does not mean to fall in love with any impossible idea. Practical implications Learning to not neglect seemingly impossible options and sometimes to reveal them can lead to sustainable competitive advantages. Social implications While generating a competitive advantage for the concerned companies, implementing impossible ideas can also contribute to make the world a better place. Originality/value The authors identify some mechanisms that can make impossible thinking beneficial and profitable for companies. These insights can help managers to nurture an environment that facilitates the emergence of pathbreaking advances.
... Permitir que el ritmo cambie durante el ejercicio reduce el esfuerzo fisiológico requerido para realizar una cantidad constante de trabajo (Lander et al., 2009). Los engaños conscientes que mejoran el rendimiento incluyen usar el espejo Ramachandran para observar el brazo no fatigado al trabajar con el brazo opuesto (Tanaka et al., 2011), escuchar música (Barwood et al., 2009Lim et al., 2009;Schneider et al., 2010), la provisión de información inexacta provista por un reloj que corre lentamente (Morton, 2009) o de la distancia real que se cubrirá (Paterson y Marino, 2004), o del ritmo de un rendimiento anterior que se había incrementado engañosamente en un 2% (Stone et al., 2012), o de las verdaderas condiciones ambientales en las que el ejercicio se está realizando y el la respuesta de temperatura corporal central real del atleta (Castle et al., 2012). ...
Book
Full-text available
This book is published by the University of Guadalajara and contents several different chapters of authors who are professors, researchers and postgraduate students on the sciences of Physical Education and Sports who belong to some educational and research institutions of Mexico and other countries. Each year is delivery a new book and this version is the correspondent of 2018.
... In addition to performance feedback, cyclists have also been shown to alter pace and/or perform faster when riding with a virtual pacing avatar in comparison to a baseline, ride-alone trial (Williams, el al. 2014: Corbett, Barwood, Ouzounoglou, Thelwell, & Dicks, 2012Stone et al., 2012). This performance enhancement is supported by classic Social Facilitation theory (Triplett, 1898), increases in motivational drive (McCormick et al., 2015), a shift to a more external attentional focus and lowered perceptions of exertion (Williams et al., 2014). ...
Article
Objectives Two studies investigated expert-novice differences in information-seeking behaviour, cognitions and performance during cycling time trials (TT). Study 1 examined trained and novice cyclist’s cognitions whilst performing a TT, using a Think Aloud (TA) protocol and eye-tracking techniques. Study 2 investigated expertise differences during alone and competitive TTs. Methods in Study 1, six trained and seven novice cyclists performed a 16.1 km TT. In Study 2, eight trained and ten novice cyclists performed three 16.1 km TT; a baseline TT, an alone TT and a trial against a virtual competitor. In both studies, participants were asked to TA and in Study 1 they also wore mobile gaze-tracking glasses. Performance feedback and a simulated TT course were visually displayed during all trials, as was a virtual avatar during the competitor trial. Verbalisations were coded into primary and secondary themes. Cognitions and pacing strategies were compared between groups and across the duration of the TTs. In Study 1, eye-tracking data for total dwell time and gaze frequency were calculated for each area of interest (Time Elapsed, Power, Heart Rate, Cadence, Distance Covered, Speed and Course Scenery). Results In Study 1, no significant differences were found in information-seeking behaviour between groups, however there were expertise differences in the cognitive strategies used. Trained cyclists’ verbalisations were more performance-relevant (i.e., power output), whereas the untrained group were more focused on task completion (i.e., distance and time) and irrelevant information. Both groups talked more about distance and motivational thoughts in the later stages of the trial, and dwell time on distance feedback also increased in this final 4 km. In Study 2, the trained group performed faster than the untrained group but there were no significant differences in pace or performance between alone and competitive TTs for either group. Differences in cognitions were found between groups and across the TT duration. Conclusion Both studies demonstrate that cognitive processes differ as a function of expertise during self-paced cycling time trials. There were no differences in information-seeking behaviour between trained and untrained cyclists and there was no effect of an opponent on pace or performance.
... The most recent review (Hurst, Schipof-Godart,et al., 2019) included 32 studies including 1,513 participants, and reported smallmoderate effects for placebo treatments (Cohen's d = 0.36), small-moderate effect for nocebo treatments (d = 0.37), and small-moderate effects when classified as nutritional (d = 0.35) and mechanical (d = 0.47) treatments. The magnitude of these improvements compares closely to the 1-3% percent gains in performance reported for widely-tested ergogenic aids such as Beet root juice (Braakhuis & Hopkins,2015), caffeine (Salinero, Lara & Del Coso, 2019), high intensity training programs (Laursen, 2010), and deceptive avatar pacing (Stone et al., 2012). ...
Article
Research over the past 15 years on the placebo effect has substantiated its contribution to the efficacy of established treatments for a range of clinical conditions and identified its underlying mechanisms. There is also evidence that placebo effects contribute to the performance benefits of many ergogenic aids, and that performance can worsen when dummy treatments are associated with expectations of a harmful outcome (i.e., the nocebo effect). Unfortunately, the bulk of sport research involving placebos and nocebos continues to be hampered by outdated definitions and conceptualizations of the placebo effect and its mechanisms. This has implications not only for research but also application, as nearly 50% of athletes report experiencing a beneficial placebo effect, and a similar proportion of coaches report providing placebos to their athletes. The objective of this paper is to attempt to stimulate research by presenting updated definitions of the placebo and nocebo effects in the context of sport, describing their major mechanisms and, highlighting the importance of the psychosocial setting in the sport setting on placebo effects.
... Williams et al. (27) addressed these concerns and revealed that power outputs were higher for subjects when a simulated avatar was used as an opponent for male cyclists. These findings are in agreement with Stone et al. (23) who used deception in a study that found male cyclists exercised at a higher power output when racing against an avatar. Although this study did not use humans or avatars as an opponent, it is possible that male weightlifters were more competitive with male spotters, which subsequently led to higher MV and PP values during the 1RM trials. ...
Article
Resistance exercise is popular because of favorable health outcomes associated with increased muscular fitness. For these reasons, 1 repetition maximum (1RM), mean velocity (MV), and peak power (PP) are of interest during the bench press. However, research has yet to evaluate whether spotter sex impacts bench press performance. Therefore, the purpose of this study was to determine the impact of spotter sex on bench press performance during a 1RM testing protocol. Twenty resistance-trained individuals (10 men and 10 women) visited the laboratory on 2 separate occasions. Estimated 1RM was self-reported by subjects before the 1RM protocol. During their visits, subjects had their 1RM (kg), MV (m·s 21), and PP (W) determined on a bench press 1RM protocol while using a male or female spotter. Deception was used by telling subjects the intent of the study was to determine the reliability of a linear position transducer for measuring MV and PP during the 1RM trials. The main findings revealed that measured 1RM values for male weightlifters were significantly higher than estimated 1RM values when using both a male (p 5 0.01) and female spotter (p , 0.01). In addition, results revealed MV and PP were significantly higher for the 1RM trials when male weightlifters had a male spotter (both p , 0.01). Alternatively, there were no significant differences in estimated vs. measured 1RM values for women as well as no effect of spotter sex on bench press strength (all p. 0.05). Practitioners should note that sex of a spotter does not seem to impact measured 1RM. However, notable influences may be observed within MV and PP.
... Stone et al. 13 lieten getrainde wielrenners een tijdrit over 4 km uitvoeren op een fietsergometer. Tijdens het fietsen keken de proefpersonen naar een scherm waarop een weg door een landschap werd geprojecteerd (zie figuur 2). ...
Article
Full-text available
Neuromusculaire vermoeidheid komt tot stand door een samenspel van centrale en perifere factoren. Onze kennis hierover is de laatste decennia sterk toegenomen. Kunnen wij die kennis ook toepassen in de (sport)praktijk?
... In sports, coaches use deception as a form of training and expecting better performance when athletes have no knowledge about their training intensities 1 . In deception experimental designs, rate of perceived exertion is a variable that represent the participant knowledge about the exercise intensity 2 . ...
Poster
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Background In sports, coaches use deception as a form of training and expecting better performance when athletes have no knowledge about their training intensities 1. The ergogenic effects of deception can be explained by Noakes and his integrative theory of fatigue 2. However, there are few methodologies using deception with resistance training. The aim of this study was to compare repetitions and rate of perceived exertion (RPE) between tests with difference loads under deception conditions. Methods Eight volunteers were recruited and performed 3 sets of bilateral elbow flexion up to concentric failure with 90 seconds resting between sets. All volunteers performed 3 test with different intensities (70%, 80% and 90% of 1 maximum repetition), in different days. To establish load increases, volunteers previously perform 1 repetition maximum test (1RM). To evaluate the RPE, it was used OMNI-RES Scale exactly after last repetition. Deception effect was made with a cardboard protection around the weights plates in each side of the bar. Volunteers did not know about the load changes between days. Descriptive analysis were shown by means and standard deviation (SD) and made through natural logarithm. To compare means ANOVA repeated measures with Bonferroni post-hoc was used with alpha P≤0.05 and Effect Size (based in Hedges’g). Complementary analysis was made through coefficient variation (CV) to standarzing the measure of dispersion and confidence interval (CI) of 95. To practical application, we showed raw data together with data transformed by natural logarithm to repetitions . Results Repetitions was different among different loads 70% (6.25±1.59 repetitions; 1.59±0.75 repetitions_log; CV=15%; CI_log=0.67 to 0.83), 80% (4.88±1.75; 0.62±0.17; CV=27%; CI_log=0.50 to 0.74) and 90% (3.13±1.70; 0.40±0.22; CV=55%; CI_log=0.25 to 0.56). Comparing sets, we found value P of 0.002 (70x80%), 0.0001 (70x90%) and 0.001 (80x90%). RPE had no differences among different loads 70% (6.33±1.59 arbitrary units; CV=25%; CI=5.23 to 7.44); 80% (7.75±0.81; CV=10%; CI=7.19 to 8.31) and 90% (8.25±0.46; CV=5%; CI=7.93 to 8.57). Comparing sets, we found value P of 0.063 (70x80%), 0.053 (70x90%) and 0.359 (80x90%) Discussion Our results show no difference in RPE observing through ANOVA, but we can observe a very large ES between 70-80% 1RM and a medium ES between 80-90% 1RM. This data can lead us to highlight that OMNI-RES is not sensible to evaluate changes in strength performance in high intensity strength training (<80% 1RM). Conclusion Deception does not improve performance when used as an ergogenic strategy in resistance training with deceive loads. References 1. Stone MR, Thomas K, Wilkinson M, Jones AM, Gibson ASC, Thompson KG. Effects of deception on exercise performance: Implications for determinants of fatigue in humans. Medicine & Science in Sports & Exercise. 2012;44(3):534. 2. Noakes TD. Time to move beyond a brainless exercise physiology: the evidence for complex regulation of human exercise performance. Appl Physiol Nutr Metab. 2011;36(1):23-35. 1. Stone MR, Thomas K, Wilkinson M, Jones AM, Gibson ASC, Thompson KG. Effects of deception on exercise performance: Implications for determinants of fatigue in humans. Medicine & Science in Sports & Exercise. 2012;44(3):534. 2. Noakes TD. Time to move beyond a brainless exercise physiology: the evidence for complex regulation of human exercise performance. Appl Physiol Nutr Metab. 2011;36(1):23-35. 3. Noakes TD, St Clair Gibson A, Lambert EV. From catastrophe to complexity: a novel model of integrative central neural regulation of effort and fatigue during exercise in humans: summary and conclusions. Br J Sports Med. 2005 Feb;39(2):120-4. PubMed PMID: 15665213. Pubmed Central PMCID: 1725112. Epub 2005/01/25. eng. 1. Stone MR, Thomas K, Wilkinson M, Jones AM, Gibson ASC, Thompson KG. Effects of deception on exercise performance: Implications for determinants of fatigue in humans. Medicine & Science in Sports & Exercise. 2012;44(3):534. 2. Noakes TD. Time to move beyond a brainless exercise physiology: the evidence for complex regulation of human exercise performance. Appl Physiol Nutr Metab. 2011;36(1):23-35. 3. Noakes TD, St Clair Gibson A, Lambert EV. From catastrophe to complexity: a novel model of integrative central neural regulation of effort and fatigue during exercise in humans: summary and conclusions. Br J Sports Med. 2005 Feb;39(2):120-4. PubMed PMID: 15665213. Pubmed Central PMCID: 1725112. Epub 2005/01/25. eng. 1. Stone MR, Thomas K, Wilkinson M, Jones AM, Gibson ASC, Thompson KG. Effects of deception on exercise performance: Implications for determinants of fatigue in humans. Medicine & Science in Sports & Exercise. 2012;44(3):534. 2. Noakes TD. Time to move beyond a brainless exercise physiology: the evidence for complex regulation of human exercise performance. Appl Physiol Nutr Metab. 2011;36(1):23-35. 3. Noakes TD, St Clair Gibson A, Lambert EV. From catastrophe to complexity: a novel model of integrative central neural regulation of effort and fatigue during exercise in humans: summary and conclusions. Br J Sports Med. 2005 Feb;39(2):120-4. PubMed PMID: 15665213. Pubmed Central PMCID: 1725112. Epub 2005/01/25. eng. 1. Stone MR, Thomas K, Wilkinson M, Jones AM, Gibson ASC, Thompson KG. Effects of deception on exercise performance: Implications for determinants of fatigue in humans. Medicine & Science in Sports & Exercise. 2012;44(3):534. 2. Noakes TD. Time to move beyond a brainless exercise physiology: the evidence for complex regulation of human exercise performance. Appl Physiol Nutr Metab. 2011;36(1):23-35. 3. Noakes TD, St Clair Gibson A, Lambert EV. From catastrophe to complexity: a novel model of integrative central neural regulation of effort and fatigue during exercise in humans: summary and conclusions. Br J Sports Med. 2005 Feb;39(2):120-4. PubMed PMID: 15665213. Pubmed Central PMCID: 1725112. Epub 2005/01/25. eng. 1. Stone MR, Thomas K, Wilkinson M, Jones AM, Gibson ASC, Thompson KG. Effects of deception on exercise performance: Implications for determinants of fatigue in humans. Medicine & Science in Sports & Exercise. 2012;44(3):534. 2. Noakes TD. Time to move beyond a brainless exercise physiology: the evidence for complex regulation of human exercise performance. Appl Physiol Nutr Metab. 2011;36(1):23-35. 3. Esteves G, Motoyama Y, Pandelo DJ, Pereira P, Pereira R, Azevedo P. Transcranial Direct Current Stimulation Before Intermittent Exercise Does Not Improve Physical Performance.: 3729 Board #168 June 4, 9: 30 AM - 11: 00 AM. Med Sci Sports Exerc. 2016 May;48(5S Suppl 1):1041. PubMed PMID: 27362095. Epub 2016/07/01. Eng. 4. Noakes TD, St Clair Gibson A, Lambert EV. From catastrophe to complexity: a novel model of integrative central neural regulation of effort and fatigue during exercise in humans: summary and conclusions. Br J Sports Med. 2005 Feb;39(2):120-4. PubMed PMID: 15665213. Pubmed Central PMCID: 1725112. Epub 2005/01/25. eng. 1. Stone MR, Thomas K, Wilkinson M, Jones AM, Gibson ASC, Thompson KG. Effects of deception on exercise performance: Implications for determinants of fatigue in humans. Medicine & Science in Sports & Exercise. 2012;44(3):534. 2. Noakes TD. Time to move beyond a brainless exercise physiology: the evidence for complex regulation of human exercise performance. Appl Physiol Nutr Metab. 2011;36(1):23-35. 3. Nakamura FY, Perandini LA, Okuno NM, Borges TO, Bertuzzi RC, Robertson RJ. Construct and concurrent validation of OMNI-Kayak rating of Perceived Exertion Scale. Percept Mot Skills. 2009 Jun;108(3):744-58. PubMed PMID: 19725310. Epub 2009/09/04. eng. 4. Esteves G, Motoyama Y, Pandelo DJ, Pereira P, Pereira R, Azevedo P. Transcranial Direct Current Stimulation Before Intermittent Exercise Does Not Improve Physical Performance.: 3729 Board #168 June 4, 9: 30 AM - 11: 00 AM. Med Sci Sports Exerc. 2016 May;48(5S Suppl 1):1041. PubMed PMID: 27362095. Epub 2016/07/01. Eng. 5. Noakes TD, St Clair Gibson A, Lambert EV. From catastrophe to complexity: a novel model of integrative central neural regulation of effort and fatigue during exercise in humans: summary and conclusions. Br J Sports Med. 2005 Feb;39(2):120-4. PubMed PMID: 15665213. Pubmed Central PMCID: 1725112. Epub 2005/01/25. eng. 1. Stone MR, Thomas K, Wilkinson M, Jones AM, Gibson ASC, Thompson KG. Effects of deception on exercise performance: Implications for determinants of fatigue in humans. Medicine & Science in Sports & Exercise. 2012;44(3):534. 2. Pereira PE, Motoyama Y, Esteves GJ, Oliveira JC, Pereira R, Pandeló D, et al. Caffeine supplementation delays the fatigue through central nervous system modulation. Sport Sciences for Health. 2016:1-7. 3. Noakes TD. Time to move beyond a brainless exercise physiology: the evidence for complex regulation of human exercise performance. Appl Physiol Nutr Metab. 2011;36(1):23-35. 4. Nakamura FY, Perandini LA, Okuno NM, Borges TO, Bertuzzi RC, Robertson RJ. Construct and concurrent validation of OMNI-Kayak rating of Perceived Exertion Scale. Percept Mot Skills. 2009 Jun;108(3):744-58. PubMed PMID: 19725310. Epub 2009/09/04. eng. 5. Esteves G, Motoyama Y, Pandelo DJ, Pereira P, Pereira R, Azevedo P. Transcranial Direct Current Stimulation Before Intermittent Exercise Does Not Improve Physical Performance.: 3729 Board #168 June 4, 9: 30 AM - 11: 00 AM. Med Sci Sports Exerc. 2016 May;48(5S Suppl 1):1041. PubMed PMID: 27362095. Epub 2016/07/01. Eng. 6. Noakes TD, St Clair Gibson A, Lambert EV. From catastrophe to complexity: a novel model of integrative central neural regulation of effort and fatigue during exercise in humans: summary and conclusions. Br J Sports Med. 2005 Feb;39(2):120-4. PubMed PMID: 15665213. Pubmed Central PMCID: 1725112. Epub 2005/01/25. eng.
... A cut-off criterion of maximum 2% time difference was used as this performance variance is unexplained by physiological processes. 205 Since it was impossible to find only exclusively matched pairs of two using this strict criteria, it was necessary for five participants to complete an additional COMPTT (Two won both trials, one lost both trials, and two won and lost one trial each). Eventually, 23 participants completed the study and an overall of 14 head-to-head competitions were investigated. ...
Thesis
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Current models of exercise regulation almost solely rely on the Gestalt phenomenon of perceived exertion. This limits a more comprehensive understanding of how cause-effect relationships come to be and how perception-action coupling determines pacing behaviour and performance fatigability. A three-dimensional framework of centrally regulated and goal-directed exercise behaviour is proposed, which differentiates between sensory-discriminatory, affective-motivational, and cognitive-evaluative processes hypothesised to underpin perceived fatigability. In short: (A) perceived physical strain and perceived mental strain are primary regulators of pacing behaviour necessary to align planned behaviour with current physiological state, (B) core affect plays a primary and mediatory role in performance regulation, and (C) the mindset- shift associated with an action crisis plays a primary role in volitional self-regulatory control and decision-making. In study one, 23 cyclists of distinct performance levels engaged in 70-km individual and head-to-head competition time trials against a performance matched opponent. Sensory constructs were primarily associated with regulation of pacing behaviour. Affective and cognitive constructs acted as context-dependent modifiers and were primarily associated with regulation of performance. A five-step structural equation modelling procedure was applied to assess the extent to which the observed data fit the hypothesised cause–effect relationships under the constraint of psychological duress: valence deterioration was found to mediate the relationship between falling-behind and action crisis, which in turn predicted increased non-adaptive endocrinological distress response, which in turn predicted performance decrement. In study two, 22 highly trained runners completed two self-paced 20-km treadmill time trials in a tapered condition and with locomotor muscle fatigue and exercise-induced muscle damage. The latter was associated with medium increases in markers of physiological distress and large alterations in perceived physical strain, affective valence, and cognitive mindset. This indicates heuristic and rational antecedents in the goal-disengagement process. Structural equation modelling confirmed the hypothesised dual-pathway model under the constraint of physical duress: haematological indicators of EIMD predicted (1) amplified physiological strain and non-adaptive endocrinological distress response and (2) increase in perceived physical strain, which mediated and predicted decrease in valence, which in turn predicted an increase in action crisis; and both physiological and perceptual effects predicted performance fatigability. The proposed framework has the potential to enrich theory development in centrally regulated and goal-directed exercise behaviour by providing novel insights into and more complete account of the dynamic and complex processes in strain-perception-thinking-action coupling during prolonged endurance exercise.
... The experimental studies (N = 16) that examined the influence of a competitor have mainly focussed on the performance effects rather than the changes in pacing. In general, an improved performance during competitive trials compared with individual or non-competitive trials has been found [99][100][101][102][103][104][105][106][107][108][109][110][111][112]. In addition, most of these studies were set-up to examine the effect of deception rather than the effect of an opponent. ...
Article
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An athlete’s pacing strategy is widely recognised as an essential determinant for performance during individual events. Previous research focussed on the importance of internal bodily state feedback, revealed optimal pacing strategies in time-trial exercise, and explored concepts such as teleoanticipation and template formation. Recently, human–environment interactions have additionally been emphasized as a crucial determinant for pacing, yet how they affect pacing is not well understood. Therefore, this literature review focussed on exploring one of the most important human–environment interactions in sport competitions: the interaction among competitors. The existing literature regarding the regulation of exercise intensity and the effect of competition on pacing and performance is critically reviewed in this paper. The PubMed, CINAHL and Web of Science electronic databases were searched for studies about pacing in sports and (interpersonal) competition between January 2000 to October 2017, using the following combination of terms: (1) Sports AND (2) Pacing, resulting in 75 included papers. The behaviour of opponents was shown to be an essential determinant in the regulation of exercise intensity, based on both observational (N = 59) and experimental (N = 16) studies. However, adjustment in the pacing response related to other competitors appears to depend on the competitive situation and the current internal state of the athlete. The findings of this review emphasize the importance of what is happening around the athlete for the outcome of the decision-making process involved in pacing, and highlight the necessity to incorporate human–environment interactions into models that attempt to explain the regulation of exercise intensity in sports and exercise.
... Finishing times of the maximal BTT were used to match participants for the CTT. A cut-off criterion of maximum 2% time difference was used, as this performance variance is unexplained by physiological processes [27]. Since it was impossible to find only exclusively matched pairs of two using this strict criteria, it was necessary for five participants to complete an additional CTT (two won both trials, one lost both trials, and two won and lost one trial each). ...
Article
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Introduction: A three-dimensional framework of centrally regulated and goal-directed exercise behaviour emphasised the integration of distinct sensory-discriminatory, affective- motivational and cognitive-evaluative dimensions that underpin perceived fatigability. This study aimed to capture the complex interdependencies and temporal dynamics in these processes, their interrelations with observed pacing behaviour, performance and biochemical variables as well as their performance level- and competition outcome-dependent variances. Methods: Twenty-three cyclists of distinct performance level categories engaged in individual and head-to-head competition time trials against a performance-matched opponent. Sensory, affective and cognitive processes were respectively assessed with the constructs perceived physical strain and perceived mental strain, valence and felt arousal underpinning core affect and action crisis characterised by a shift from an implemental to a deliberative mindset. Results: Performance level- and competition outcome-dependent variances and differential temporal dynamics in constructs were associated with alterations in pacing behaviour, performance and physiological disturbance. Perceived physical and mental strain were primarily associated with observed pacing behaviour as necessary to align planned behaviour with current physiological state. Valence and arousal were primarily associated with differential responses in performance regulation. The mindset shift associated with an action crisis was primarily associated with non-adaptive, psycho-neuro-endocrinological distress response. Conclusion: The proposed constructs are interdependent in a nonlinear dynamic fashion, context dependent, constraint based, distinguishable by well-trained cyclists and interrelated with observed pacing behaviour, performance and physiological disturbance. The proposed framework provides a more comprehensive alternative to the Gestalt concept of perceived exertion and more completely accounts for centrally regulated and goal-directed exercise behaviour.
... Blanchfield, Hardy, De Morree, Staiano, and Marcora (2014) reported that even slight and subtle motivation can override the controlling function of the central governor, making it useless. Similarly, ample research shows that several deception strategies can be used to trick the brain into exerting more effort (Morton, 2009;Paterson & Marino, 2004;Stone, Thomas, Wilkinson, Jones, et al., 2012). Critics consider these findings a serious limitation of the central governor model, since it cannot execute its controlling function, and so it becomes irrelevant (Inzlicht & Marcora, 2016). ...
Article
We investigated how runners' trait emotional intelligence (trait EI) influences their performance. Participants, recruited the day before a half marathon competition, were asked to report their experience and performance in previous races and to complete a trait EI questionnaire. Through a structural equation modeling approach, we demonstrated that runners' trait EI was the main predictor of runners' finish time. Specifically, trait EI emerged as the variable with the highest power to predict finish time over and above training. Overall, these results are consistent with the explanation that being effective at controlling emotions reduces the impact of fatigue and leads to better performance.
... Laboratory studies in cooler environments have shown improved 2000-m cycling performance when athletes believed they were competing against another participant in a simulated race, but were actually competing against an avatar of their own solo performance [15]. Similarly, participants who believed they were 'racing' against a previous 4000-m cycling time trial (TT), but were actually racing against an avatar with a 2% higher power, matched the superior performance [16]. If pacing is a thermoregulatory behaviour, it is important to understand the effect of competition on pacing, performance and thermoregulation during exercise in hot conditions. ...
Article
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Background It has been suggested that pacing is a thermoregulatory behaviour. We investigated the effect of competition on pacing, performance and thermophysiological strain during exercise in the heat and the psychological factors mediating competition effects. Method Eighteen males (maximum oxygen uptake [VO2max] 3.69 [0.44] L min−1) undertook a preliminary 20-km cool (wet-bulb globe temperature [WBGT] 12 °C) cycling time trial (TT) and three experimental 20-km trials (balanced order): (i) cool TT (CoolSolo); (ii) hot (WBGT 26 °C) TT (HotSolo); (iii) hot head-to-head competition (HotH2H). During TTs, an avatar of the participant’s performance was visible. During HotH2H, participants believed they were competing against another participant, but the competitor’s avatar replicated their own preliminary (cool) TT. ResultsTTs (min:sec [SD]) slowed with increased ambient temperature [CoolSolo 35:31 (2:11) versus HotSolo 36:10 (2:26); p = 0.011]. This effect was negated by competition; performances were not different between HotH2H [35:17 (1:52)] and CoolSolo (p = 0.160) and were quicker in HotH2H versus HotSolo (p = 0.001). End-exercise rectal temperature, mean body temperature and physiological strain index were (p < 0.05) higher in HotH2H than either solo condition. Despite faster performance and greater thermophysiological strain, rating of perceived exertion (RPE), thermal comfort and sensation, and perceptual strain index were not different between HotH2H and HotSolo. The difference in end-exercise rectal temperature between HotH2H and HotSolo was related to pre-exercise anticipatory heart rate response (r = 0.608, p = 0.010) and participants’ propensity for deliberate risk-taking (B = 0.12, p < 0.001), whereas self-reported resilience predicted change in performance times between HotH2H versus HotSolo (B = − 9.40, p = 0.010). Conclusion Competition changes the relationship between perceived and actual thermophysiological state, altering behavioural thermoregulation and increasing thermophysiological strain; this could increase heat-illness risk. Psychophysiological and psychological measures may identify susceptible individuals.
... The 2% increase in speed (∼5.8% increase in power output) may have exceeded the functional increment which can elicit a further improvement in performance. Other work which implemented a deceptive 5% increment in speed and power respectively above baseline failed to yield any improvement in performance in 20 km (Micklewright et al., 2010) and 4 km (Stone, 2012) TTs. The magnitude of the deceptive feedback manipulation in these studies might have been so great as to not escape detection by participants, who then adopted a conservative pacing strategy. ...
... Laboratory based cycling time trials (TTs) have been extensively used in the literature as exercise performance criteria. Distances of between 4 (Altareki et al. 2009; Stone et al. 2012) and 40 km (Jones et al. 2015a; Maunder et al. 2016) are most frequently used in cycling based research. Performance of these TTs typically represent exercise times of approximately 5- 65 minutes in trained cyclists, and it is this wide spectrum which elicits diverse physiological responses, allowing the scrutiny of a broad range of experimental designs. ...
Article
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Laboratory based cycling time trials (TT) are widely used by both researchers and practitioners, as a method of assessing cycling performance in a controlled environment. Assessments of performance often use TT durations or distances between 20 min and one hour and in the UK the 10 mile (16.1 km) TT is the most frequently used race distance for trained cyclists. The 16.1 km TT has received relatively minimal, but increased attention as a performance criterion in the literature. Therefore, the aim of this study was to assess the reliability of 16.1 km TT performance in a large cohort of trained cyclists using the CompuTrainer cycling ergometer. Trained male cyclists (n = 58, mean±SD age 35±7 yr, height 179±6 cm, weight 79.1±9.4 kg, VO2max. 56.6±6.6 ml.kg.min-1, PPO 365±37 W) performed an initial incremental exercise test to determine PPO and VO2max. The participants then performed two 16.1 km TT on a CompuTrainer cycle ergometer separated by 3-7 days. Differences in time, power output and speed were determined using a Wilcoxon signed ranks or paired t-tests. Reproducibility of the TT performance measures was performed using the coefficient of variation (CV), intraclass correlations, and typical error (TE). There were no differences between any of the performance criteria for the whole cohort (Mean difference = 0.06 min, 0.09 km.h-1, 1.5 W, for time, mean speed and power respectively) between TT1 and TT2. All TT performance data were very reproducible (CV range = 1.1-2.7%) and demonstrated trivial or small TE. The slower cyclists demonstrated marginally lower reliability (CV range = 1.3-3.2%) compared to the fastest group (CV range = 0.7-2.0%). The 16.1 km TT on the CompuTrainer represents a very reliable performance criterion for trained cyclists. Interpretation of test-retest performance outcomes should be performed in the context of the TE of each performance indicator.
... For example, it has been shown that conditioned beliefs about performance strongly influence early pacing behaviour despite unsustainably high levels of perceived exertion [70], suggesting that in some circumstances the self-belief heuristic might have a stronger influence on decisions than the perceived exertion heuristic. In a number of other studies, the actions of a competitor have been strongly associated with pace change [71][72][73], perhaps indicating that, in some situations, it might be strategically advantageous to act in ways that would otherwise be contraindicated by the corresponding perceived exertion trajectory. ...
Article
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The extent to which athletic pacing decisions are made consciously or subconsciously is a prevailing issue. In this article we discuss why the one-dimensional conscious-subconscious debate that has reigned in the pacing literature has suppressed our understanding of the multidimensional processes that occur in pacing decisions. How do we make our decisions in real-life competitive situations? What information do we use and how do we respond to opponents? These are questions that need to be explored and better understood, using smartly designed experiments. The paper provides clarity about key conscious, preconscious, subconscious and unconscious concepts, terms that have previously been used in conflicting and confusing ways. The potential of dual process theory in articulating multidimensional aspects of intuitive and deliberative decision-making processes is discussed in the context of athletic pacing along with associated process-tracing research methods. In attempting to refine pacing models and improve training strategies and psychological skills for athletes, the dual-process framework could be used to gain a clearer understanding of (1) the situational conditions for which either intuitive or deliberative decisions are optimal; (2) how intuitive and deliberative decisions are biased by things such as perception, emotion and experience; and (3) the underlying cognitive mechanisms such as memory, attention allocation, problem solving and hypothetical thought.
... Similarly, lesions in the ascending reticular activating system suggest that reductions in arousal may mediate some aspects of fatigue in individuals with postpolio syndrome (37). Even in healthy individuals, however, psychological factors, such as performance feedback, can influence the average power produced by trained cyclists when performing a time trial as quickly as possible, which presumably coincides with maximal ratings of perceived exertion at the end of the task (66). ...
Article
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Despite flourishing interest in the topic of fatigue-as indicated by the many presentations on fatigue at the 2015 annual meeting of the American College of Sports Medicine-surprisingly little is known about its impact on human performance. There are two main reasons for this dilemma: (1) the inability of current terminology to accommodate the scope of the conditions ascribed to fatigue, and (2) a paucity of validated experimental models. In contrast to current practice, a case is made for a unified definition of fatigue to facilitate its management in health and disease. Based on the classic two-domain concept of Mosso, fatigue is defined as a disabling symptom in which physical and cognitive function is limited by interactions between performance fatigability and perceived fatigability. As a symptom, fatigue can only be measured by self-report, quantified as either a trait characteristic or a state variable. One consequence of such a definition is that the word fatigue should not be preceded by an adjective (e.g., central, mental, muscle, peripheral, and supraspinal) to suggest the locus of the changes responsible for an observed level of fatigue. Rather, mechanistic studies should be performed with validated experimental models to identify the changes responsible for the reported fatigue. As indicated by three examples (walking endurance in old adults, time trials by endurance athletes, and fatigue in persons with multiple sclerosis) discussed in the review, however, it has proven challenging to develop valid experimental models of fatigue. The proposed framework provides a foundation to address the many gaps in knowledge of how laboratory measures of fatigue and fatigability impact real-world performance.
... This study adds onto this knowledge by showing that the performance improvement when an opponent is present, is also independent of the pacing profile of the opponent. The presence of a competitive opponent, independent of its pacing behavior, seems to enable the participants to use a greater degree of their physiologic capacity that cannot be fully accessed when competing alone [23] . In fact, previous literature showed a greater anaerobic energy capacity could be achieved during time trials when an opponent was present [6]. ...
Article
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Introduction: The present study aimed to explore how athletes respond to different behaviors of their opponents. Methods: Twelve moderately to highly physically active participants with at least two years of cycling experience completed four 4-km time trials on a Velotron cycle ergometer. After a familiarization time trial (FAM), participants performed three experimental time trials in randomized order with no opponent (NO), a virtual opponent who started slower and finished faster compared to FAM (OP-SLOWFAST), or a virtual opponent who started faster and finished slower compared to FAM (OP-FASTSLOW). Repeated-measures ANOVAs (P<0.05) were used to examine differences in pacing and performance related to power output, velocity and RPE. Results: OP-SLOWFAST and OP-FASTSLOW were completed faster compared to NO (385.5±27.5, 385.0±28.6, and 390.6±29.3s, respectively). An interaction effect for condition×distance (F=3.944, P<0.001) indicated differences in pacing profiles between conditions. Post-hoc analysis revealed that a less aggressive starting strategy was adopted in NO compared to OP-FASTSLOW and OP-SLOWFAST during the initial 1000m. Finally, a faster starting opponent evokes higher power outputs by the participants in the initial 750m compared to a slower starting opponent. Conclusion: The present study is the first to show that the behavior of an opponent affects pacing-related decisions in laboratory-controlled conditions. Our findings support the recently proposed interdependence of perception and action, and emphasize the interaction with the environment as an important determinant for an athlete's pacing decisions, especially during the initial stages of a race.
... Thus, modulations in pace, which are a function of biologically and cognitively orchestrated afferent signals, and the consequent homeostatically orientated efferent responses are manifest in order to prevent a complete depletion of the finite anaerobic capacity. 2,3 This cognitive judgment is set within the context of a continuum of information from the ability to anticipate the metabolic demands and to select an appropriate strategy through the accumulation of prior experience for completion of such a task that has a known end point. 1,4,5 The significance of prior experience to the pacing paradigm was recently exemplified in works that demonstrated enhanced pace modulation and effort control in individuals, who were more experienced and well-trained than less-experienced counterparts. ...
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Abstract: To assess pacing accuracy in a group of adolescent swimmers during an incremental step test. Fifteen well-trained swimmers (age 15±1.5 years; height 170.2±8.8 cm; mass 60.2±6.6 kg), completed two 7×200 m tests, separated by ∼72 hours. They swam to a predetermined incrementally increasing pace per step and were instructed to swim at even pace. Upon completion of each step, rating of perceived exertion, heart rate and blood lactate were recorded. Significant differences observed for both trials between actual and predicted swim time (P,0.05). Significant differences also observed between the first and second 100 m of each step in trial 1 for step 1 (P=0.001, effect size [ES] =0.54), step 2 (P=0.0001, ES =0.57), step 4 (P=0.0001, ES =0.53), step 5 (P=0.005, ES =0.65), step 6 (P=0.0001, ES =0.50), and step 7 (P=0.0001, ES =0.70). Similar responses witnessed for trial 2 (P,0.05). Findings suggest that the finite anaerobic capacity was engaged sooner than would normally be anticipated, as a function of an inability to regulate pace. This is proposed to be a consequence of the volume of exposure to the biological and psychological sensations and cognitive developmental status. Given the apparent error in pacing judgment exhibited in this population group, caution should be applied when adopting such tests to monitor training responses with adolescent athletes, and alternate means of modulating pace be investigated. Keywords: effort regulation, children, exercise testing, perception
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Mental fatigue induced by an earlier cognitive task can impair performance on a subsequent physical task. The current study investigated whether such performance impairment could be mitigated by performance feedback. In an experimental sequential-task design, 63 sport science students completed a series of three tasks: 5-min physical (pre-test), 20-min cognitive, 5-min physical (post-test). Participants were randomly allocated to one of three groups: feedback (n = 23), no feedback (n = 20), control (n = 20). The physical tasks, which assessed force production during a self-paced rhythmic handgrip task as a measure of physical endurance performance, were performed with (feedback group) or without (no feedback group, control group) visual performance feedback. The cognitive tasks involved either completing a 2-back memory task to induce mental fatigue (feedback and no feedback groups) or watching a didactic film (control group). Self-report measures (fatigue, exertion, vigor, motivation) were collected throughout. The 2-back cognitive task increased mental fatigue, mental exertion and general fatigue in the feedback and no feedback groups compared to the control group. Relative to the pre-test physical task, post-test endurance performance declined in the no feedback group (−14.4%) but did not change in the control (−2.6%) and feedback (−2.4%) groups. This mitigation of performance effect was not accompanied by parallel changes in fatigue, exertion, vigor, or motivation. In conclusion, visual performance feedback mitigates the negative effects of mental fatigue on physical endurance performance.
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RESUMO: O teste contrarrelógio (TCR), ou teste de resistência com término previamente estabelecido pelas dimensões tempo ou distância, é utilizado como meio de avaliação do desempenho de corredores em uma situação com variação livre da velocidade.Tanto o aprendizado motor, isto é, a transição de uma situação nova para rotina,quanto o processamento de informações dimensionais, são aspectos cognitivos que podem influenciar o resultado do TCR. Portanto, procurou-se avaliar a influência da informação dimensional exclusiva do tempo transcorrido ou da distância percorrida na reprodutibilidade do desempenho (i.e. tempo total) entre dois TCRs em situação novidade. Adicionalmente, a estratégia de corrida de um TCR-rotina foi comparada ao TCR-novidade para avaliar a influência do aprendizado no desempenho. Para este fim, seis corredores amadores realizaram dois TCRs de 3000m (T3000)com 15 dias de intervalo como linha de base. O T3000 fazia parte da rotina dos últimos três anos de treinamento. Ao longo dos 15 dias, foram realizados duas duplicatas de TCRs-novidade com intervalos de 48h entre as repetições. Os TCRs-novidade duplicados foram testes repetidos em distâncias idênticas não vivenciadas previamente. Na duplicata 1, os corredores tiveram informação do tempo transcorrido e, na duplicata 2, da distância percorrida.Todos os corredores utilizaram aparelho GPS. Observou-se que a informação exclusiva da distância ou do tempo não influenciou a reprodutibilidade do desempenho do TCR-novidade. Contudo, os corredores apresentaram uma estratégia de corrida em "W", com maior velocidade média, reproduzida apenas nos testes T3000-rotina. Portanto, os corredores apresentaram uma estratégia de corrida mais eficiente e específica no T3000-rotina que não foi reproduzida em distâncias similares em situação novidade. O estudo aponta para o desenvolvimento de métodos de treinamento de corrida que aprimorem a transição da habilidade apresentada na rotina de treinamento para uma situação de novidade. Palavras-chave: Teste Contrarrelógio; Corredores; Estratégia de Corrida; Desempenho; Aprendizado Motor. HOHL, R; SILVA, C E; AUGUSTO, J B. Influência do aprendizado e da informação espaço-tempo no desempenho de corredores em testes contrarrelógio. R. bras. Ci. e Mov 2015;23(1): ABSTRACT: The time trial (TT) test, previously set by time or distance, is used to evaluate the performance in a situation where power or speed is freely changed by the athlete. The motor learning, namely the transition between novelty to routine, and the processing of dimensional information may influence the pacing strategy and time trial performance. Therefore, our purpose was to evaluate the influence of elapsed time or distance covered feedback on the reproducibility of performance (i.e. total time) comparing two TTs in novelty, that is, with dimensions never experienced before. In addition, the pacing of a TT in routine, that is, with dimension experienced several times, was compared with the TT in novelty to assess the influence of learning on performance. Six amateur runners performed two 3000m TT (3000TT) within fifteen days as baseline. The 3000TT was the test of routine for the last three years of running training. Along the 15 days, two TT in novelty with different dimensions were duplicated with 48h between each trial. Along the TT in novelty, runners had the feedback of elapsed time (duplicate 1) or distance covered (duplicate 2), exclusively. All runners used a GPS device during the trials. We found that exclusive information of elapsed time or distance covered did not influence the time trial's reproducibility. Nevertheless, the runners showed a "W-shape" pacing, with the highest average speed only reproduced within the two 3000TT routine tests. Therefore, the runners showed a more efficient and specific pacing strategy during the TT in routine which was not reproduced during the TTs in novelty with similar dimensions. Our study highlights the importance of training methods that transpose the performance of a routine ability to novel contexts.
Thesis
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