Social support plays an important role in our physical and mental health, and is also recognised as a key factor for the success and well-being of athletes. It would be of significant interest for researchers and practitioners to identify the components of perceived and received social support, support antecedents, and subsequent consequences of support. The first aim of this thesis was to apply a univariate generalisability theory approach to examine the components of perceived and received support. The second aim was to apply a multivariate generalisability theory approach to identify the antecedents and consequences of perceived and received support across different levels of analysis. Four studies were conducted applying either a fully crossed or partially nested design to examine components of social support when athletes rated coaches or their most important support providers within their existing social networks. Further, in Studies 3 and 4, participants also completed a performance task in the presence of support providers. Univariate analyses demonstrated that consistently across all studies the relational and social components accounted for the largest amount of variance in both perceived and received support. These findings suggest that perceivers rated certain providers to be particularly supportive, in comparison to how they rated other providers. Across all studies multivariate analyses revealed that provider personality and social identity related to perceptions of support at the relational and social level. In Studies 1 and 4, coach competency also related to perceptions of support at the relational and social level. When athletes perceived certain providers to exhibit specific personality traits, particularly the trait of agreeableness, felt certain coaches were highly competent, and shared a common identity with providers, those providers were also perceived to be particularly supportive. Studies 3 and 4, however, were unable to identify antecedents of received support at any level of analysis, suggesting that perceived and received support have distinct antecedents. Further, in Studies 3 and 4, perceived and received support had unique relationships with self-confidence and performance across the different components. At the perceiver and trait level, when athletes felt they generally received support from providers, they generally felt more confident. In comparison, at the relational and social level, if athletes perceived certain providers to be particularly supportive, they performed better in their presence. The support received from those providers was also beneficial through enhancing self-confidence and, in turn, performance. The findings from the current thesis significantly further conceptual understanding of perceived and received support by identifying their correlates at the different levels of analysis. The current thesis also offers evidence based recommendations for social support interventions.

This thesis examined the influence of support type and support visibility on the effects of enacted social support on performance and a number of key psychological and behavioural variables. It comprises five chapters. Chapter 1 is a general introduction. The next three chapters (outlined below) present the results of four studies. Chapter 5 is a general discussion. Chapter 2 examined how support type and support visibility influenced the effects of natural support exchanges between athletes and their key support providers occurring in the week prior to an athlete’s match. Athletes and key support providers reported respectively the receipt and provision of support during this week. Athletes also indicated their self-confidence and emotional states regarding the upcoming the match. Moderated hierarchical regression analyses revealed that all types of received support predicted athletes’ emotional states and self-confidence regarding the upcoming match. There was no evidence that invisibly providing these support types predicted athletes’ outcomes. For informational support, however, it was found that its provision predicted self-confidence, suggesting that athletes’ levels of confidence may have benefited from advice that they were not always aware of. Chapter 3 employed an experimental paradigm to better examine the influence of the type and visibility of enacted social support. Using a golf-putting task with novices (n = 105), it examined the influence of informational and esteem support provided in a visible or invisible manner by a fellow novice golfer. This fellow novice golfer was in reality a confederate scripted to give one of five support manipulations (visible informational support, invisible informational support, visible esteem support, invisible esteem support, no support) to participants prior to performing the golf-putting task. The results demonstrated that participants given invisible informational support or visible esteem support outperformed those given no support, while participants given visible informational support or invisible esteem support did not. There was no evidence that participants’ self-efficacy or emotional states could explain these effects. Chapter 4 also involved experimental procedures across two separate studies with samples of skilled football players completing a football aiming task. In these studies, esteem and informational support was provided in a visible or invisible manner by a coach with expertise in penalty-taking. In the first of these studies, the players (n = 68) performed better when the expert provided them with informational support than when the expert provided them with esteem support. This effect occurred regardless of whether the support was provided in a visible or invisible manner. Self-efficacy could not explain this effect. Given the lack of effects of support visibility, the second of these two studies was designed as a replication and an extension of the first. It sought to further examine why informational support might be more effective than esteem support for skilled football players (n = 84). Consistent with the first study, kicking performance was again significantly better for players provided with informational support than for players provided with esteem support regardless of whether the support was provided in a visible or invisible manner. There was evidence that players given informational support performed better than those given esteem support, because their attention was focused more externally on the target and less internally on the process of movement execution. This series of studies are important for sport and social psychology: They are the first to explore the effect of support type and support visibility in a sport context; and they are the first to examine the effect of support type and support visibility in relation to performance. The results demonstrate that support type is a crucial factor to consider when exchanging support. However, no support type may necessarily be considered the best under all conditions. In light of explaining the effects of different support types on performance, the final study suggests that attentional focus may be an important underlying mechanism. The results indicate that support visibility may play a role in the exchange of support but its influence depends on the type of support provided and the context in which this type of support is provided. An overriding finding of this thesis is that enacted support can have beneficial effects upon athletes’ psychological states and performance.

Moderne Fahrzeuginformationssysteme ermöglichen es dem Fahrer, während der Fahrt auf eine Vielzahl an geographischen Informationen wie Sonderziele zuzugreifen. Die Auswahl einer Option aus solch umfangreichen Angeboten während der Fahrt kann jedoch zu einem erheblichen Sicherheitsrisiko werden, welches eine Unterstützung des Fahrers bei der Optionsauswahl erforderlich macht. Eine vielversprechende Möglichkeit der Unterstützung liegt im Anbieten von Assistenzsystemen zur personalisierten Sonderzielauswahl. Ziel der hier vorliegenden Dissertation ist die Optimierung der Akzeptanz solcher Assistenzsysteme im fahrzeugspezifischen Nutzungskontext. Hierzu wurde in einer qualitativen Studie zunächst der Nutzungskontext untersucht. Aufbauend auf den Ergebnissen und der Taxonomie für Assistenzsysteme nach Wandke (2005) wurden drei Assistenzarten mit verschiedenen Assistenzgraden identifiziert, die potentiell für die personalisierte Optionsauswahl im Fahrzeug in Frage kommen (adaptierbare Filterassistenz, adaptive Filterassistenz, adaptive Delegationsassistenz). In zwei Szenariobefragungen konnte mit Hilfe des UbiTAM nach Rothensee (2010) aufgezeigt werden, dass alle drei Assistenzarten positiv bewertet wurden. Innerhalb dieser positiven Bewertungen wurden höhere Assistenzgrade signifikant besser bewertet. Basierend auf den Erkenntnissen wurden die Assistenzarten prototypisch realisiert und in zwei Fahrsimulationsstudien hinsichtlich ihrer Auswirkung auf die Fahrleistung und die Güte der Aufgabenbearbeitung untersucht. In den Studien konnten die Ergebnisse zur Akzeptanzbeurteilung bestätigt werden. Zusätzlich wurde deutlich, dass die adaptiven Assistenzarten das höchste Maß an Unterstützung in der Nebenaufgabe boten. Gleichzeitig zeigten sie auch die geringste Auswirkung auf die Fahrleistung. Die Ergebnisse dieser Arbeit legen für die Gestaltung von Auswahlassistenzsystemen im Fahrzeug nahe, eine Kombination aus adaptiven Filter- und Delegationsassistenzen anzustreben. / Modern vehicle information systems allow the driver to access a variety of geographical information, like points-of-interest, whilst driving. However, selecting an option from an extensive list of options, whilst driving, can pose a significant safety hazard. Thus, it becomes essential to support the driver in this selection process. A promising solution lies in supplying an assistance system that includes a personalised points-of-interest selection. The purpose of this doctoral thesis is to optimise the acceptance of those assistance systems. Firstly, a qualitative study was carried out to examine the context of use. The results were analysed using the taxonomy for assistance systems developed by Wandke (2005). This identified three suitable types of option selection assistance systems, with varying levels of support; adaptable filter assistance, adaptive filter assistance, adaptive delegation assistance. Secondly, the assistance systems were analysed by means of scenario surveys based on the UbiTAM, by Rothensee (2010). The results showed that all three assistance systems were rated positive. Within these positive ratings, those systems offering higher levels of support received significantly better ratings. Based on the findings all three assistance systems were implemented as prototypes. The prototypes were evaluated in two driving simulator studies, in order to assess their effects on both the driving performance and the quality of task processing. The simulator studies verified the results uncovered by the scenario surveys. Additionally, it became clear that adaptive assistance systems provided drivers with the most support during the fulfilment of secondary tasks. Finally, they showed that driving performance was only slightly affected by the use of the adaptive assistance systems. In terms of the development of assistance systems, the results of this thesis suggest that a combination of adaptive filter and delegation assistance should be implemented.