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Elite Youth Soccer Players’ Sources and Types of Soccer Confidence
Get PDFSport confidence is a psychological characteristic considered vital for youth soccer players to possess. However, only limited research has explored the types and sources of sport confidence important to elite youth performers in professional soccer academies. Semi-structured interviews were conducted with 11 academy footballers (aged 10 or 11). Abductive hierarchical content analysis identified types of confidence to include achievement, skill execution, psychological factors, superiority to opposition and tactical awareness. Key sources of confidence identified by players were performance accomplishments, coaching, social support, and preparation. Even though the dimensions reported were similar to previous research, a number of unique sub-themes of confidence sources emerged, including pre-training/competition emotions, coach and team-mate feedback. The results demonstrate the importance of considering maturation levels and context when seeking to understand and develop confidence in youth performers
Political advances for women and sport in the mid-1990s
Get PDFThe topic of women and girls’ rights, access and inclusion in sport and physical activity has become a mainstay of sporting and non-sporting organisational discourse. Notwithstanding, there is little published on why, how and who enabled these topics to become politicised to this extent. For example, academic texts state key moments for the advancement of women and sport, such as conferences and resolutions, but rarely provide further detail. By explaining how transnational women and sport advocacy groups lobbied the United Nations (UN) and the International Olympic Committee (IOC) into actions for women and sport in the mid-1990s, this article adds to knowledge about how advocacy groups in international sport succeeded in working together to collectively effect change despite demonstrating contention amongst one another. Data from archival analysis of papers and correspondence of key agents involved in these processes were complemented with semi-structured interviews with some of the same individuals decades later. Using terms and concepts from social movement studies, the article shows how the International Working Group on Women and Sport (IWG) and WomenSport International (WSI) developed in relation to each other and the political environment in which they were playing a key role in shaping. Their relationship was not straightforward, due in part to the formations and structure of each group, but their purposive efforts with other agents contributed to a collective endeavour that achieved milestones for the political legitimacy of women and sport
Effects of spaceflight on musculoskeletal health: a systematic review and meta-analysis, considerations for interplanetary travel
Get PDFIf interplanetary travel is to be successful over the coming decades, it is essential that countermeasures to minimize deterioration of the musculoskeletal system are as effective as possible, given the increased duration of spaceflight associated with such missions. The aim of this review, therefore, is to determine the magnitude of deconditioning of the musculoskeletal system during prolonged spaceflight and recommend possible methods to enhance the existing countermeasures.
Methods
A literature search was conducted using PubMed, Ovid and Scopus databases. 5541 studies were identified prior to the removal of duplicates and the application of the following inclusion criteria: (1) group means and standard deviations for pre- and post-spaceflight for measures of strength, muscle mass or bone density were reported (or provided by the corresponding author when requested via e-mail), (2) exercise-based countermeasures were included, (3) the population of the studies were human, (4) muscle function was assessed and (5) spaceflight rather than simulated spaceflight was used. The methodological quality of the included studies was evaluated using a modified Physiotherapy Evidence Database (PEDro) scale for quality, with publication bias assessed using a failsafe N (Rosenthal method), and consistency of studies analysed using I2 as a test of heterogeneity. Secondary analysis of studies included Hedges’ g effect sizes, and between-study differences were estimated using a random-effects model.
Results
A total of 11 studies were included in the meta-analyses. Heterogeneity of the completed meta-analyses was conducted revealing homogeneity for bone mineral density (BMD) and spinal muscle size (Tau2 0.05), although a high level of heterogeneity was noted for lower body force production (Tau2 = 1.546; I2 = 76.03%, p < 0.001) and lower body muscle mass (Tau2 = 1.386; I2 = 74.38%, p < 0.001). The estimated variance (≤ -0.306) for each of the meta-analyses was significant (p ≤ 0.033), for BMD (− 0.48 to − 0.53, p < 0.001), lower body force production (− 1.75, p < 0.001) and lower body muscle size (− 1.98, p < 0.001). Spaceflight results in small reductions in BMD of the femur (Hedges g = − 0.49 [− 0.69 to – 0.28]), trochanter (Hedges g = − 0.53 [− 0.77 to – 0.29]), and lumbo-pelvic region (Hedges g = − 0.48 [− 0.73 to – 0.23]), but large decreases in lower limb force production (Hedges g = − 1.75 [− 2.50 to – 0.99]) and lower limb muscle size (Hedges g = − 1.98 [− 2.72 to – 1.23]).
Conclusions
Current exercise countermeasures result in small reductions in BMD during long-duration spaceflight. In contrast, such exercise protocols do not alleviate the reductions in muscle function or muscle size, which may be attributable to the low to moderate loads reported by crewmembers and the interference effect associated with concurrent training. It is recommended that higher-load resistance exercise and the use of high-intensity interval training should be investigated, to determine if such modifications to the reported training practices result in more effective countermeasures to the deleterious effect of long-duration spaceflight on the muscular system
Inter-methodological quantification of the target change for performance test outcomes relevant to elite female soccer players
Get PDFIntroduction: Valid and informed interpretations of changes in physical performance test data are important within athletic development programmes. At present, there is a lack of consensus regarding a suitable method for deeming whether a change in physical performance is practically relevant or not.
Methods: We compared true population variance in mean test scores between those derived from evidence synthesis of observational studies to those derived from practioner opinion (n = 30), and to those derived from a measurement error (minimal detectable change) quantification (n = 140). All these methods can help to obtain ‘target’ change score values for performance variables.
Results: We found that the conventional ‘blanket’ target change of 0.2 (between-subjects SD) systematically underestimated practically relevant and more informed changes derived for 5-m sprinting, 30-m sprinting, CMJ, and Yo-Yo Intermittent Recovery Level 1 (IR1) tests in elite female soccer players.
Conclusions: For the first time in the field of sport and exercise sciences, we have illustrated the use of a principled approach for comparing different methods for the definition of changes in physical performance test variables that are practically relevant. Our between-method comparison approach provides preliminary guidance for arriving at target change values that may be useful for research purposes and tracking of individual female soccer player’s physical performance
Real-time multi-objective optimisation for electric vehicle charging management
Get PDFThe continuous increase in the uptake of electric vehicles and the interest to use electric vehicles to provide energy services require commercially viable business models for all involved stakeholders. It is, however, challenging to achieve the synergy among different stakeholders since their objectives are often conflicting. This work proposes a real-time multi-objective optimisation method where electric vehicle charging/discharging profile is scheduled in real-time to strike a balance among different objectives, namely electricity cost reduction, battery degradation minimisation and grid stress alleviation as well as meeting the electric vehicle user charging requirement by fulfilling the departure time. Dynamic programming is adopted due to its computational efficiency, which is suitable for real-time applications. The effectiveness of the proposed method is demonstrated using a residential case study where the house is equipped with an electric vehicle and a photovoltaic system, and is validated by experimental implementation. The results show that the proposed multi-objective optimisation algorithm achieves the set objectives to satisfy the stakeholders’ priorities and provides a profit for the electricity end-user that is double as compared to that achieved by a benchmark multi-objective algorithm. The results demonstrate the effectiveness of the proposed multi-objective method and its suitability for real-time charging/discharging scheduling
The effects of a competitive soccer match on jump performance and inter-limb asymmetries in elite academy soccer players
Get PDFThe purpose of the present study was to investigate the effects of a competitive soccer match on jump performance and inter-limb asymmetries over incremental time points during a 72-hour (h) period. Fourteen elite adolescent players from a professional English category three academy performed single leg countermovement jumps (SLCMJ) pre, post, 24, 48, and 72-h post-match on a single force platform. Eccentric impulse, concentric impulse, peak propulsive force, jump height, peak landing force, and landing impulse were monitored throughout. Inter-limb asymmetries were also calculated for each metric as the percentage difference between limbs. Significant negative changes (p < 0.05) in jump performance were noted for all metrics at all time points, with the exception of jump height. Inter-limb asymmetries were metric-dependent and showed very large increases, specifically post-match, with a trend to reduce back towards baseline values at the 48-h time point for propulsive-based metrics. Asymmetries for landing metrics did not peak until the 24-h time point and again reduced towards 16 baseline at 48-h. The present study highlights the importance of monitoring distinct jump metrics, as jump height alone was not sensitive enough to show significant changes in jump performance. However, inter-limb asymmetries were sensitive to fatigue with very large increases post-match. More frequent monitoring of asymmetries could enable practitioners to determine whether existing imbalances are also 20 associated with reductions in physical performance or increased injury risk
‘Resilient when it comes to death’: Exploring the significance of bereavement for the well-being of social work students
Get PDFThis article describes a pilot qualitative research study, exploring the impact of bereavement experiences, on pre-qualifying social work students in two UK Universities with diverse demographics. The research study took place in the context of general concern about the mental health of UK University students and suggests that social work students may be at particular risk of developing emotional wellbeing issues linked to bereavement. Interviews followed a free association narrative technique, with analysis of the data highlighting four main themes. Firstly, bereavement is associated with practical problems which may trigger wellbeing issues. Secondly, there is an increased need for specific bereavement training and support to be embedded within social work programmes, alongside skills and knowledge of cultural diversity and the part this plays in the bereavement process. Lastly, the study demonstrated that bereavement experiences are not isolated but linked to other losses and therefore students may need effective support to process these before they can effectively support others. The study appears to be distinctive in its focus on the impacts of bereavement on social work students and has significant implications for the ways in which students are supported by social work education programmes, as well as paving the way for further research in this area
A valid and reliable test of technical skill for vision impaired football
Get PDFThe International Paralympic Committee requires international federations to develop and implement sport-specific classification guidelines based on scientific evidence. As a result of these requirements, new evidence-based criteria are required in football for athletes with vision impairment (VI). Performance tests are key to the development of a new classification system. Therefore, the aim of this study was to develop a valid and reliable test of technical performance for VI football. To assure content and face validity, the Vision Impaired Football Skills (VIFS) test was based on recommendations from experienced players and coaches. To test construct validity, we compared 24 sighted football players that were split into two groups based on highest-level of performance achieved but matched on experience. To test reliability all players completed the VIFS three times on two separate days. Results supported construct validity through detecting significant differences in performance times between the two groups (p = .004, g = 1.28 95% CI = 0.41 - 2.15). The small bias between visits (.54s ± 2.93s; 95% LoA = -5.21– 6.29) and intraclass correlations (.81, 95% CI = .56 - .92) showed between-day agreement and reliability. Within-day reliability was good when participants had completed a familiarisation trial. Results support the suitability for the use of the VIFS test for classification research. Future work should establish feasibility for players with a VI
