72 research outputs found
Reliability of Change of Direction and Agility Assessments in Youth Soccer Players
Considering the vast physical and neural developments experienced throughout adolescence, the reliability of physical performance may vary in youth populations. This study aimed to examine the reliability of change of direction (COD) and agility tests in youth soccer players. Altogether, 86 youth soccer players, aged 13.6 ± 2.0 years, volunteered to participate. Data were collected from a modified 505 COD test (m505COD) and the Y-sprint drill in both pre-planned (Y-SprintPRE) and reactive (Y-SprintREACT) conditions during 2 sessions, 7 days apart. Anthropometric data including body mass, standing stature, and sitting height were also collected. COD and agility tests demonstrated good reliability (ICC = 0.81â0.91; CV = 1.2â2.0; d = 0.00â0.31; p < 0.01) for our entire sample. However, we observed a small negative relationship between age and intersession differences for the Y-SprintPRE (r = â0.28; p = 0.04), and moderate negative relationships between both age (r = â0.41; p < 0.01), and maturity offset (r = â0.39; p < 0.01) for the Y-SprintREACT. Although the COD and agility tests adopted within this study possess good intersession reliability, we observed greater intersession differences for younger and less mature individuals. We suggest that while COD and agility tests may provide meaningful objective data for monitoring the development of youth soccer players, these tests should be used with caution when evaluating younger, more immature athletes
âHeâs Just a Wee Laddieâ: The Relative Age Effect in Male Scottish Soccer
Significant structural, developmental, and financial constraints exist in Scottish soccer that may predicate a different approach to talent identification and development. To our knowledge, no published reports exist evaluating the prevalence of the relative age effect (RAE) in Scottish soccer players. Consequently, the aim of this study was to investigate the prevalence of the RAE among varied playing levels and ages of male Scottish youth soccer players. Birthdates of male youth players (n = 1,230) from U10 to U17 age groups and from playing levels: âAmateurâ (n = 482), âDevelopmentâ (n = 214), and âPerformanceâ (n = 534), alongside a group of male Scottish senior professional players (n = 261) were recorded and categorized into quartiles (Q1 = JanuaryâMarch; Q2 = AprilâJune; Q3 = JulyâSeptember; and Q4 = OctoberâDecember) and semesters (S1 = JanuaryâJune and S2 = JulyâDecember) from the start of the selection year. Birthdates were analyzed for: (a) each playing level and (b) each age group irrespective of playing level. For the varied playing levels examined, an RAE was evident in âDevelopmentâ and âPerformanceâ playing levels only at youth level. When examining each age group, an RAE was observed in U12âU17 players only. While there was a slight asymmetry favoring Q1 born senior professional players, the RAE was not present within this group of our sample. Results from our study suggest that a bias in selecting individuals born earlier in the selection year may exist within male soccer academy structures, but not at amateur level. The asymmetry favoring chronologically older players at youth but not professional level questions the efficacy of this (un)conscious bias within male Scottish soccer players
Selected, Deselected, and Reselected: A Case Study Analysis of Attributes Associated With Player Reselection Following Closure of a Youth Soccer Academy
Considering the perceived benefit of early recruitment and the time and resources spent developing youth players, individuals released from talent development programmes are often re-recruited by rival academies. However, due to the contractual nature of many talent development programmes, limited empirical data exists on players deselected from (or reselected to) youth soccer academies. Adopting a novel case study approach, differences in skill, psychological, and physical attributes associated with reselection following closure of a junior-elite soccer academy were explored. Overall subjective coach ratings for skill, psychological, and physical abilities; subjective coach ratings for skill and psychological attributes; and physical fitness test performance of 79 junior-elite soccer players (U11âU17) were assessed as part of regular scheduled testing and monitoring practices prior to the academy closure. Reselection status was monitored and recorded for all players in the 6 months following the academy closure and was classified as a persistence/progression (âReselectedâ) or attrition (âDeselectedâ) in playing level. Of the 79 released players, a total of 60 players (76%) were re-signed to a junior-elite academy within 6 months. Differences were observed for overall ratings of skill, psychological, and physical abilities in favor of the âReselectedâ player group. âReselectedâ players were also rated higher by coaches for all attributes categorized as skill and psychological, as well as performing better at all physical fitness tests. However, âReselectedâ players were lesser in stature and body mass and less mature than âDeselectedâ players. Our findings suggest that reselection is not a product of anthropometric criteria and, therefore, a pathway for selection remains open for later maturing players. We also inform upon desirable qualities associated with player reselection and provide a case study approach of a unique, yet highly relevant, scenario for talent identification and development in youth soccer
Exploring Talent Identification in Australian Rules Football: The Nuances of the Athlete Recruitment Process
The process of talent identification and recruitment is a key element of the elite athlete talent pathway. As such, it is important to understand the information and specific processes used by expert recruiters to inform talent identification decisions. Therefore, the purpose of this study was to examine the perspectives of talent identifiers in relation to their conceptions of talent and the information they collect and interpret to inform their talent identification decisions. Participating in the study were 13 heads of recruitment at elite Australian Football League clubs. They were deemed experts in their field and were responsible for the selection and recruitment of players at their respective clubs. Data were collected through semi-structured interviews conducted via teleconferencing, with thematic analysis used to identify key themes. Thematic analysis of interview data generated two first order themes: (1) Understanding Talent and (2) Talent Identification Process. Four second order themes emerged from the data: (1a) Defining Talent, (1b) Athlete Attributes, (2a) Talent List Development, and(2b) Recruiter Tasks. From these second order themes, 12 associated third order themes were produced (e.g., projecting growth/athlete potential, initial identification process, refining the list, and the final decision). In particular, the findings highlight how the recruiters assess talent based on game performance and athlete intent (i.e., "giving 100%"), rather than performance at physical testing sessions, and the psychological profile of the athletes. Overall, the findings emphasize the complexity associated with elite-level talent identification and provide insight for practitioners and researchers aiming to understand and explain the talent identification process
Exploring Talent Identification in Australian Rules Football: The Nuances of the Athlete Recruitment Process
The process of talent identification and recruitment is a key element of the elite athlete talent pathway. As such, it is important to understand the information and specific processes used by expert recruiters to inform talent identification decisions. Therefore, the purpose of this study was to examine the perspectives of talent identifiers in relation to their conceptions of talent and the information they collect and interpret to inform their talent identification decisions. Participating in the study were 13 heads of recruitment at elite Australian Football League clubs. They were deemed experts in their field and were responsible for the selection and recruitment of players at their respective clubs. Data were collected through semi-structured interviews conducted via teleconferencing, with thematic analysis used to identify key themes. Thematic analysis of interview data generated two first order themes: (1) Understanding Talent and (2) Talent Identification Process. Four second order themes emerged from the data: (1a) Defining Talent, (1b) Athlete Attributes, (2a) Talent List Development, and(2b) Recruiter Tasks. From these second order themes, 12 associated third order themes were produced (e.g., projecting growth/athlete potential, initial identification process, refining the list, and the final decision). In particular, the findings highlight how the recruiters assess talent based on game performance and athlete intent (i.e., "giving 100%"), rather than performance at physical testing sessions, and the psychological profile of the athletes. Overall, the findings emphasize the complexity associated with elite-level talent identification and provide insight for practitioners and researchers aiming to understand and explain the talent identification process
Evaluation of multi-directional speed qualities throughout adolescence in youth soccer: the non-linear nature of transfer
Training and assessment of agility is often prioritised by soccer coaches and practitioners aiming to develop multi-directional speed. Although the importance of agility is advocated throughout childhood and adolescence, limited data evidence agility performance at different stages of adolescence. The purpose of this study was to examine differences in multi-directional speed performance in youth soccer players spanning an entire soccer academy. A total of 86 male junior-elite soccer players volunteered to participate. Anthropometric data were collected, alongside performance data from a battery of physical tests including sprinting, jumping, change of direction, reaction time, and agility. Bayesian models using log-likelihoods from posterior simulations of parameter values displayed linear or curvilinear relationships between both chronological and biological age and performance in all tests other than agility and reaction time. For agility and reaction time tests, performance improved untilâ~14âyears of age or the estimated age of peak height velocity whereby arrested development in performance was observed. Our results demonstrate that while most performance skills improve as chronological or biological age increases, measures of agility and reaction time may not. These findings support the notion that agility performance is complex and multifaceted, eliciting unique, challenging physical demands and non-linear development
Quantifying measures to limit wind driven resuspension of sediments for improvement of the ecological quality in some shallow Dutch lakes
Although phosphorus loadings are considered the main pressure for most shallow lakes, wind-driven resuspension can cause additional problems for these aquatic ecosystems. We quantified the potential effectiveness of measures to reduce the contribution of resuspended sediments, resulting from wind action, to the overall light attenuation for three comparable shallow peat lakes with poor ecological status in the Netherlands: Loosdrecht, Nieuwkoop, and Reeuwijk (1.8â2.7 m depth, 1.6â2.5 km fetch). These measures are: 1. wave reducing barriers, 2. water level fluctuations, 3. capping of the sediment with sand, and 4. combinations of above. Critical shear stress of the sediments for resuspension (Vcrit), size distribution, and optical properties of the suspended material were quantified in the field (June 2009) and laboratory. Water quality monitoring data (2002â2009) showed that light attenuation by organic suspended matter in all lakes is high. Spatial modeling of the impact of these measures showed that in Lake Loosdrecht limiting wave action can have significant effects (reductions from 6% exceedance to 2% exceedance of Vcrit), whereas in Lake Nieuwkoop and Lake Reeuwijk this is less effective. The depth distribution and shape of Lake Nieuwkoop and Lake Reeuwijk limit the role of wind-driven resuspension in the total suspended matter concentration. Although the lakes are similar in general appearance (origin, size, and depth range) measures suitable to improve their ecological status differ. This calls for care when defining the programme of measures to improve the ecological status of a specific lake based on experience from other lakes.
Exploring the role of socioeconomic status and psychological characteristics on talent development in an English soccer academy
Social factors and psychological characteristics can influence selection and development in talent pathways. However, the interaction between these two factors is relatively unknown. The aim of this study was to investigate the implications of socioeconomic status and psychological characteristics in English academy soccer players (nâ=â58; aged 11 to 16âyears). To assess socioeconomic status, participantsâ home postcodes were coded according to each individualâs social classification and credit rating, applying the UK General Registrar Classification system and CameoTM geodemographic database, respectively. Participants also completed the six factor Psychological Characteristics for Developing Excellence Questionnaire (PCDEQ). A classification of âhigher-potentialsâ (nâ=â19) and âlower-potentialsâ (nâ=â19) were applied through coach potential rankings. Data were standardised using z-scores to eliminate age bias and data were analysed using independent sample t-tests. Results showed that higher-potentials derived from families with significantly lower social classifications (pâ=â0.014) and reported higher levels for PCDEQ Factor 3 (coping with performance and developmental pressures) (pâ=â0.007) compared to lower-potentials. This study can be used to support the impetus for researchers and practitioners to consider the role of social factors and psychological characteristics when selecting and developing sporting talent. For example, facilitating player-centred development within an academy and, where necessary, providing individuals with additional support
Bulk and element specific magnetism of the medium and high entropy Cantor-Wu alloys
Magnetic Compton scattering, x-ray magnetic circular dichroism spectroscopy
and bulk magnetometry measurements are performed on a set of medium (NiFeCo and
NiFeCoCr) and high (NiFeCoCrPd and NiFeCoCrMn) entropy Cantor-Wu alloys. The
bulk spin momentum densities determined by magnetic Compton scattering are
remarkably isotropic, and this is a consequence of the smearing of the
electronic structure by disorder scattering of the electron quasiparticles.
Non-zero x-ray magnetic circular dichroism signals are observed for every
element in every alloy indicating differences in the populations of the
majority and minority spin states implying finite magnetic moments. When Cr is
included in the solid solution, the Cr spin moment is unambiguously
antiparallel to the total magnetic moment, while a vanishingly small magnetic
moment is observed for Mn, despite calculations indicating a large moment. Some
significant discrepancies are observed between the experimental bulk and
surface magnetic moments. Despite the lack of quantitative agreement, the
element specific surface magnetic moments seem to be qualitatively reasonable
Mucedorus: the last ludic playbook, the first stage Arcadia
This article argues that two seemingly contradictory factors contributed to and sustained the success of the anonymous Elizabethan play Mucedorus (c. 1590; pub. 1598). First, that both the initial composition of Mucedorus and its Jacobean revival were driven in part by the popularity of its source, Philip Sidney's Arcadia. Second, the playbook's invitation to amateur playing allowed its romance narrative to be adopted and repurposed by diverse social groups. These two factors combined to create something of a paradox, suggesting that Mucedorus was both open to all yet iconographically connected to an elite author's popular text. This study will argue that Mucedorus pioneered the fashion for âcontinuationsâ or adaptations of the famously unfinished Arcadia, and one element of its success in print was its presentation as an affordable and performable version of Sidney's elite work. The Jacobean revival of Mucedorus by the King's Men is thus evidence of a strategy of engagement with the Arcadia designed to please the new Stuart monarchs. This association with the monarchy in part determined the cultural functions of the Arcadia and Mucedorus through the Interregnum to the close of the seventeenth century
- âŠ