Ego depletion and persistent performance in a cycling task

We tested the assumption that persistent performance in an exhausting indoor cycling task would depend on momentarily available self-control strength (N = 20 active participants). In a within-subjects design (two points of measurement, exactly seven days apart), participants’ self-control strength was experimentally manipulated (depletion: yes vs. no; order counterbalanced) via the Stroop test before the participants performed a cycling task. In line with our hypothesis, hierarchical linear modelling (HLM) revealed that participants consistently performed worse over a period of 18 minutes when they were ego depleted. In addition, HLM analysis revealed that depleted participants invested less effort in the cycling task, as indicated by their lower heart rate. This effect escalated over time, as indicated by a time × condition interaction. These results indicate that self-control strength is necessary to obtain an optimal level of performance in endurance tasks requiring high levels of persistence. Practical implications are discussed.

Holistic patterns as an instrument to predict performance of promising young football players

Multidimensional talent models represent the current state of the art. However, it remains unclear how these different dimensions interact. Based on current theories of human development, person-oriented approaches seem to be particularly appropriate for talent research. The present study adopts this approach by looking at how a holistic system consisting of the different dimensions motivation, motor behaviour and the stage of development goes along with athletic performance. For this purpose, it has to be examined which patterns were formed by the constructs net hope (Elbe et al., 2003), motor abilities (3 motor tests; Höner et al., 2014), technical skills (3 motor tests; Höner et al., 2014) and the so far achieved percentage of the predicted adult height (Mirwald et al, 2002) and how these patterns are related to subsequent sporting success. 119 young elite football players were questioned and tested three times at intervals of one year, beginning at the age of 12. At the age of 15, the performance level the players had reached was examined (national, regional or no talent card). At all three measuring points, four patterns were identified which displayed partial structural and high individual stability. As expected, the players showing values above average in all factors were significantly more likely to advance to the highest performance level (Odds ratio = 2.2, p < .01). Physically strong, precocious developed players though having some technical weaknesses, have good chances to reach the middle performance level (OR = 1.6, p = .01). Players showing values under average, have an one and a half times higher probability to advance to the lowest performance level (p < .01). The results point to the importance of holistic approaches for the prediction of performance among promising football talents in the medium-term and thus provide valuable clues for their selection and promotion.

Ego depletion and action initiation

Optimal sprint start performance requires the self-control of responses. Therefore, start performance should depend on self-control strength. It was expected that momentary depletion of self-control strength (ego depletion) would slow down the initiation of a sprint start, resulting in impaired reaction times. N = 37 participants performed three sprint starts at T1 and the average reaction times were measured with a foot-pressure release system attached under the starting block (in ms). Next, participants were randomly assigned to a depletion or a non-depletion condition and self-control strength was experimentally manipulated by applying the transcription task. Following the depletion manipulation, participants performed another series of three sprints (T2). The results of a mixed between (ego depletion: yes vs. no) within (T1 vs. T2) ANOVA supported the hypothesis as average reaction times in the depletion condition significantly increased from T1 (M = 0.35, SD = 0.03) to T2 (M = 0.38, SD = 0.04), F(1, 35) = 6.77, p = .01, η2p = .16. Average reaction times in the non-depletion condition did not differ significantly between T1 (M = 0.36, SD = 0.03) and T2 (M = 0.35, SD = 0.04), F(1, 35) = 0.47, p = .50, η2p = .01. In line with the hypothesis, higher levels of self-control strength were associated with quicker movement initiations. Therefore, improving self-control strength may serve as a buffer against the negative effects of ego depletion on performance.

Ego depletion and attention regulation under pressure: Is a temporary loss of self-control strength indeed related to impaired attention regulation?

In the present study we investigated whether ego depletion negatively affects attention regulation under pressure in sports by assessing participants’ dart throwing performance and accompanying gaze behavior. According to the strength model of self-control the most important aspect of self-control is attention regulation (Schmeichel & Baumeister, 2010). As higher levels of state anxiety are associated with impaired attention regulation (Nieuwenhuys & Oudejans, 2012) we chose a mixed design with ego depletion (yes vs. no) as between-subjects and anxiety level (high vs. low) as within-subjects factor. A total of 28 right-handed students participated in our study (Mage = 23.4, SDage = 2.5; 10 female; no professional dart experience). Participants performed a perceptual-motor task requiring selective attention, namely, dart throwing. The task was performed while participants were positioned high and low on a climbing wall (i.e., with high and low levels of anxiety). In line with our expectations, a mixed-design ANOVA revealed that depleted participants in the high anxiety condition performed worse (p < .001) and displayed a shorter final fixation on bull’s eye (p < .01) than in the low anxiety condition, demonstrating that when one is depleted attention regulation under pressure cannot be maintained. This is the first study that directly supports the general assumption that ego depletion is a major factor in influencing attention regulation under pressure.

Effects of (un)predictable whole body vibrations on visual performance

Over recent years, it has repeatedly been shown that optimal gaze strategies enhance motor control (e.g., Foulsham, 2015). However, little is known, whether, vice versa, visual performance can be improved by optimized motor control. Consequently, in two studies, we investigated visual performance as a function of motor control strategies and task parameters, respectively. In Experiment 1, 72 participants were tested on visual acuity (Landolt) and contrast sensitivity (Grating), while standing in two different postures (upright vs. squat) on a ZEPTOR-platform that vibrated at four different frequencies (0, 4, 8, 12 Hz). After each test, perceived exertion (Borg) was assessed. Significant interactions were revealed for both tests, Landolt: F(3,213)=13.25, p<.01, ηp2=.16, Grating: F(3,213)=4.27, p<.01, ηp2=.06, elucidating a larger loss of acuity/contrast sensitivity with increasing frequencies for the upright compared with the squat posture. For perceived exertion, however, a diametrical interaction for frequency was found for acuity, F(3,213)=7.45, p<.01, ηp2=.09, and contrast sensitivity, F(3,213)=7.08, p < .01, ηp2=.09, substantiating that the impaired visual performance cannot be attributed to exertion. Consequently, the squat posture could permit better head and, hence, gaze stabilization. In Experiment 2, 64 participants performed the same tests while standing in a squat position on a ski-simulator, which vibrated with two different frequencies (2.4, 3.6 Hz) and amplitudes (50, 100 mm) in a predictable or unpredictable manner. Control strategies were identified by tracking segmental motion, which allows to derive damping characteristics. Considerable main effects were found for frequency, all F’s(1,52)>10.31, all p’s<.01, all ηp2’s>.16, as well as, in the acuity test, for predictability, F(1,52)=10.31, p<.01, ηp2=.17, and by tendency for amplitude, F(1,52)=3.53, p=.06, ηp2=.06. A significant correlation between the damping amplitude in the knee joint and the performance drop in visual acuity, r=-.97, p<.001, again points towards the importance of motor control strategies to maintain optimal visual performance.

Detecting single-target changes in multiple object tracking: The case of peripheral vision

In sports games, it is often necessary to perceive a large number of moving objects (e.g., the ball and players). In this context, the role of peripheral vision for processing motion information in the periphery is often discussed especially when motor responses are required. In an attempt to test the capability of using peripheral vision in those sports-games situations, a Multiple-Object-Tracking task that requires to track a certain number of targets amidst distractors, was chosen to determine the sensitivity of detecting target changes with peripheral vision only. Participants’ primary task was to recall four targets (out of 10 rectangular stimuli) after six seconds of quasi-random motion. As a second task, a button had to be pressed if a target change occurred (Exp 1: stop vs. form change to a diamond for 0.5 s; Exp 2: stop vs. slowdown for 0.5 s). Eccentricities of changes (5-10° vs. 15-20°) were manipulated, decision accuracy (recall and button press correct), motor response time and saccadic reaction time (change onset to saccade onset) were calculated and eye-movements were recorded. Results show that participants indeed used peripheral vision to detect changes, because either no or very late saccades to the changed target were executed in correct trials. Moreover, a saccade was more often executed when eccentricities were small. Response accuracies were higher and response times were lower in the stop conditions of both experiments while larger eccentricities led to higher response times in all conditions. Summing up, it could be shown that monitoring targets and detecting changes can be processed by peripheral vision only and that a monitoring strategy on the basis of peripheral vision may be the optimal one as saccades may be afflicted with certain costs. Further research is planned to address the question whether this functionality is also evident in sports tasks.

The impact of absolute importance and processing overlaps on prospective memory performance

Prospective memory is the ability to remember an intention at an appropriate moment in the future. Prospective memory tasks can be more or less important. Previously, importance was manipulated by emphasizing the importance of the prospective memory task relative to the ongoing task it was embedded in. This resulted in better prospective memory performance but also ongoing task costs. In the present study, we simply instructed one group of participants that the prospective memory task was important (i.e., absolute importance instruction) and compared them to a group with relative importance instructions and a control group. The results showed that absolute importance lead to an increase in prospective memory performance without enhancing ongoing task costs, whereas relative importance resulted in both increased prospective memory performance and ongoing task costs. Thus, prospective memory can be enhanced without ongoing task costs, which is particularly crucial for safety-work contexts.

The Quiet Eye in Motor Performance and Learning – Functional and Theoretical Considerations

High precision in motor skill performance, in both sport and other domains (e.g. surgery and aviation), requires the efficient coupling of perceptual inputs (e.g. vision) and motor actions. A particular gaze strategy, which has received much attention within the literature, has been shown to predict both inter- (expert vs. novice) and intra-individual (successful vs. unsuccessful) motor performance (see Vine et al., 2014). Vickers (1996) labelled this phenomenon the quiet eye (QE) which is defined as the final fixation before the initiation of the crucial phase of movement. While the positive influence of a long QE on accuracy has been revealed in a range of different motor skills, there is a growing number of studies suggesting that the relationship between QE and motor performance is not entirely monotonic. This raises interesting questions regarding the QE’s purview, and the theoretical approaches explaining its functionality. This talk aims to present an overview of the issues described above, and to discuss contemporary research and experimental approaches to examining the QE phenomenon. In the first part of the talk Dr. Vine will provide a brief and critical review of the literature, highlighting recent empirical advancements and potential directions for future research. In the second part, Dr. Klostermann will communicate three different theoretical approaches to explain the relationship between QE and motor performance. Drawing upon aspects of all three of these theoretical approaches, a functional inhibition role for the QE (related to movement parameterisation) will be proposed.

The effects of benefit finding on athletes’ quality of adjustment to career termination

Retirement from elite sports requires athletes to cope with adjustments on an occupational, financial, physical, social or emotional level. Research on critical life events (e.g., Filipp & Aymanns, 2010) suggests that benefit finding, defined as “the process of deriving positive growth from adversity” (Cassidy et al., 2014), may have a positive impact on this transition. The present study examined the effects of benefit finding on the quality of adjustment to career termination in the short, middle and long term. Former Swiss elite athletes (N = 290) completed a written survey collecting information on a) their emotional reaction to career termination, b) the amount of adjustment in various respects, c) situational characteristics of their career termination, d) the duration and quality of the transition, and e) their subjective well-being. Using Latent Variable Modelling, finding benefit in career termination was found to have both a direct and an indirect effect on long-term well-being (γ=.18). It predicts favorable emotional reactions to career termination (γ = .53) and less adjustment (γ = -.38) which in turn shortens the transition duration (β = -.15 and β = .55, respectively) and quality (β = -.15), and finally augments well-being (β = .41). The data suggest that a focus on benefit finding in both crisis-prevention and crisis-coping interventions may prove useful to prevent crisis transitions.

Perceptions of critical situations involving football fans: the dynamics of conflict escalation or de-escalation

Fan violence in the context of football matches has drawn the attention of stakeholders and the media. This phenomenon has also attracted the scientific community’s attention, where research mostly focused on reasons for violence escalation. The Elaborated Social Identity Model (ESIM; Drury & Reicher, 2000) for example focuses on group-interactions and social identities, while the Aggravation Mitigation Model (AM model; Hylander & Guvå, 2010) concentrates on factors contributing to an escalation or a non-escalation of group-violence. However individual perceptions of the different persons involved in potential conflicts have not been sufficiently examined. Beside of that research in domestic football or involving ultrafans is scarce. Especially in Switzerland, there is a lack of research concerning the dynamics of the development or non-development of fan violence. This exploratory study included eight critical situations from the season 2012/2013 of the Swiss premier league to gather data about the perceptions of various persons involved (fans, police officers or security) and the dynamics contributing towards escalation or de-escalation. Fifty-nine narrative interviews were conducted and analysed with interpretative phenomenological analysis (Smith, Flowers, & Larkin, 2009). The individuals involved (fans, police and security personnel) showed groupspecific perceptions and a tendency to stereotype the opponent group. Provocative symbols (balaclavas or riot-gear uniforms) were important for the interpretation of the situation. No escalation occurred when successful communication and sufficient distance between the groups was established. Knowledge about the local fan culture is important, because it influences the perception of legitimacy on the side of the fans. This study improves the understanding of fan violence and is congruent with the ESIM and the AM model. It is suggested to deploy police dialogue teams without riot gear. Their task is to establish direct communication with the fans to facilitate a peaceful ending of a critical situation.

Identifying observable criteria defining a critical situation involving football fans: an expert focus group study

Critical situations (CSs) involving football fans is a well-researched phenomenon with most studies examining factors leading to an escalation of violence (e.g. Braun & Vliegenthart, 2008). However, research so far has fallen short of analysing CSs that do not escalate (e.g. Hylander & Guvå, 2010) as well as establishing observable criteria that constitute such CSs. Granström et al. (2009), for instance, put forward a definition of a CS describing such situations as characterised by a discrepancy between peace and war-making behaviours between police and demonstrators. Still, this definition remains vague and does not provide concrete, defining criteria that can be identified on site. The present study looks beyond fans’ violent acts per se and focuses on these situations with a potentially – but not necessarily - violent outcome. The aim of this preliminary study is to identify observable criteria defining such a CS involving football fans. This focus group comprised of five experts working with football fans in the German-speaking area of Switzerland who discussed observable characteristics of a CS. Inductive content analysis led to the identification of specific criteria such as, “arrest of a fan”, “insufficient distance (<30m) between fans and police” and “fans mask themselves”. These criteria were then assigned to four phases of a CS highlighting the dynamic aspect of this phenomenon: Antecedents, Causes, Reactions, Consequence. Specifically, Causes, Reactions and Consequences are observable on site, while Antecedents include relevant, background information directly influencing a CS. This study puts forward a working definition of a CS that can facilitate the assessment of actual situations in the football context as well as for further research on fan violence prevention and control. These results also highlight similarities with studies investigating fan violence in other European countries while acknowledging unique characteristics of the Swiss German fan culture.

Punitive reactions to completed crimes versus accidentally uncompleted crimes

Previous studies have shown that the harm caused by crime affects punitive reactions even if differences in the degree of harm are merely accidental. However, it remains unclear whether the effect is direct or whether it is mediated by attributed responsibility or blame. Participants were 303 university students who listened to 4 case vignettes (between-subjects design). Half received information about a completed crime and half about an accidentally uncompleted crime. Crime type was either fraud or rape. The results suggest that individuals consider the actual harm to a significantly greater extent than attribution theory would predict. Moreover, the link between harm and punishment was virtually not mediated by attributed blame and not moderated by individual differences in morality. Future studies should investigate whether the harm-punishment link is a result of an automatic act of retaliation or a desire to compensate for the harm done to the victim (restorative justice).

Effects of team Knowledge and ecological constraints on decisional processes in customized football game scenarios

Several theories assume that successful team coordination is partly based on knowledge that helps anticipating individual contributions necessary in a situational task. It has been argued that a more ecological perspective needs to be considered in contexts evolving dynamically and unpredictably. In football, defensive plays are usually coordinated according to strategic concepts spanning all members and large areas of the playfield. On the other hand, fewer people are involved in offensive plays as these are less projectable and strongly constrained by ecological characteristics. The aim of this study is to test the effects of ecological constraints and player knowledge on decision making in offensive game scenarios. It is hypothesized that both knowledge about team members and situational constraints will influence decisional processes. Effects of situational constraints are expected to be of higher magnitude. Two teams playing in the fourth league of the Swiss Football Federation participate in the study. Forty customized game scenarios were developed based on the coaches’ information about player positions and game strategies. Each player was shown in ball possession four times. Participants were asked to take the perspective of the player on the ball and to choose a passing destination and a recipient. Participants then rated domain specific strengths (e.g., technical skills, game intelligence) of each of their teammates. Multilevel models for categorical dependent variables (team members) will be specified. Player knowledge (rated skills) and ecological constraints (operationalized as each players’ proximity and availability for ball reception) are included as predictor variables. Data are currently being collected. Results will yield effects of parameters that are stable across situations as well as of variable parameters that are bound to situational context. These will enable insight into the degree to which ecological constraints and more enduring team knowledge are involved in decisional processes aimed at coordinating interpersonal action.

The strengh model of self-control in sport and exercise psychology

The strength model of self-control assumes that all acts of self-control (e.g., emotion regulation, persistence) are empowered by a single global metaphorical strength that has limited capacity. This strength can become temporarily depleted after a primary self-control act, which, in turn, can impair performance in subsequent acts of self-control. Recently, the assumptions of the strength model of self-control also have been adopted and tested in the field of sport and exercise psychology. The present review paper aims to give an overview of recent developments in self-control research based on the strength model of self-control. Furthermore, recent research on interventions on how to improve and revitalize self-control strength will be presented. Finally, the strength model of self-control has been criticized lately, as well as expanded in scope, so the present paper will also discuss alternative explanations of why previous acts of self-control can lead to impaired performance in sport and exercise.