Body composition of English Premier League soccer players: Influence of playing position,international status,and ethnicity

Abstract

Body composition is a key consideration in the physical make-up of professional soccer players. The aims of the present study were to determine whether the body composition of professional soccer players varied according to playing position, international status or ethnicity, and to establish which variables best distinguished the soccer players from a reference group. Body composition was assessed using dual-energy X-ray absorptiometry in 64 male professional soccer players. Measured variables included bone mineral density and the relative amounts of lean and fat mass. Data were analysed using analysis of variance and stepwise discriminant function. The soccer players recorded better values than a reference group (n = 24) for all body composition compartments. Percent lean mass and bone mineral density were the variables best able to identify the soccer players (95.5% correctly classified). Differences in body composition were evident between goalkeepers and outfield players, but not between outfield playing positions. No differences were found on the basis of international status. The non-Caucasian players demonstrated significantly lower percent body fat (9.2 ± 2.0%) than the Caucasian players (10.7 ± 1.8%). It was concluded that body composition is important for elite soccer players, but that homogeneity between players at top professional clubs results in little variation between individuals.     

Determination of the swing technique characteristics and performance outcome relationship in golf driving for low handicap female golfers

Abstract

Previous studies on the kinematics of the golf swing have mainly focused on group analysis of male golfers of a wide ability range. In the present study, we investigated gross body kinematics using a novel method of analysis for golf research for a group of low handicap female golfers to provide an understanding of their swing mechanics in relation to performance. Data were collected for the drive swings of 16 golfers using a 12-camera three-dimensional motion capture system and a stereoscopic launch monitor. Analysis of covariance identified three covariates (increased pelvis–thorax differential at the top of the backswing, increased pelvis translation during the backswing, and a decrease in absolute backswing time) as determinants of the variance in clubhead speed (adjusted r ² = 0.965, P < 0.05). A significant correlation was found between left-hand grip strength and clubhead speed (r = 0.54, P < 0.05) and between handicap and clubhead speed (r = ?0.612, P < 0.05). Flexibility measures showed some correlation with clubhead speed; both sitting flexibility tests gave positive correlations (clockwise: r = 0.522, P < 0.05; counterclockwise: r = 0.711, P < 0.01). The results suggest that there is no common driver swing technique for optimal performance in low handicap female golfers, and therefore consideration should be given to individual swing characteristics in future studies.     

Strategy selection for cognitive skill acquisition depends on task demands and working memory capacity

The involvement of working memory capacity (WMC) in ruled-based cognitive skill acquisition is well-established, but the duration of its involvement and its role in learning strategy selection are less certain. Participants (N = 610) learned four logic rules, their corresponding symbols, or logic gates, and the appropriate input–output combinations in three-gate circuit patterns. Participants practiced 120 repetitions of each rule (480 total gates) over the course of 10 training blocks. Memory load varied between subjects. The confluence of task demands and individual differences in WMC (N = 518) dramatically affected speed–accuracy tradeoffs and strategic use of a computerized help function. Cluster analysis revealed five distinct groups of participants based on the combination of response accuracy, latency, and help use. Some groups with moderate to high mean WMC acquired the task with predictable performance patterns. Other groups, prevalently under a memory load and with low mean WMC, failed to learn or overused help.     

Applied positive psychology: Improving everyday life,health, schools,work, and society

Multiple disciplines guide our practice, but none is more relevant than the wholesome approach of positive psychology. In Applied Positive Psychology: Improving Everyday Life, Health, Schools, Work, and Society (2011), the editors address four core areas: society, human development, institutional organizations, and future directions. The strength of this book lies in its comprehensive compilation of research‐based, applied, and integrated practices for improving the living, working, and social conditions of those we strive to help every day. Applied Positive Psychology: Improving Everyday Life, Health, Schools, Work, and Society (ISBN: 978‐0‐415‐87781‐7) is published by Routledge.     

Evaluating fifth- and sixth-grade students’ expository writing: task development, scoring, and psychometric issues

Drawing from multiple theoretical frameworks representing cognitive and educational psychology, we present a writing task and scoring system for measurement of students’ informative writing. Participants in this study were 72 fifth- and sixth-grade students who wrote compositions describing real-world problems and how mathematics, science, and social studies information could be used to solve those problems. Of the 72 students, 69 were able to craft a cohesive response that not only demonstrated planning in writing structure but also elaboration of relevant knowledge in one or more domains. Many-facet Rasch Modeling (MFRM) techniques were used to examine the reliability and validity of scores for the writing rating scale. Additionally, comparison of fifth- and sixth-grade responses supported the validity of scores, as did the results of a correlational analysis with scores from an overall interest measure. Recommendations for improving writing scoring systems based on the findings of this investigation are provided.     

Sport-specific factors predicting player retention in junior cricket

Understanding factors that motivate young athletes to continue participation in sport can help key stakeholders cultivate an environment that fosters long-term participation. This investigation sought to determine the performance and participation factors that influenced continued participation in junior cricket. Administration-level data were collected each annual season across a seven-year period by a community-level junior cricket association in Australia and analysed to identify the performance and participation-based predictors of player retention. All players were males aged <16 years. Players were categorised according to whether they remained in (or departed from) the association at the end of each playing season. A multivariate logistic regression model with a stepwise variable selection was employed to identify significant independent predictors of player retention. The number of innings batted and overs bowled were significant participation-related contributors to junior cricket player retention. Performance factors such as the number of wickets taken and the number of runs scored also significantly influenced player retention. Finally, team age group, the number of previous seasons played and age were also significant factors in player retention. This demonstrates that sufficient opportunity for children to participate in the game and expression of skills competence are key factors for retention in cricket.     

All I really needed to know I learned during gastrulation

Note from the Editor     

Matters of Form: Questions of Race,Identity, Design,and the U.S. Census

This case examines how functionalist approaches manifest culturally based on users’ contexts. The authors conduct a critical visual semiotic analysis of the race and Hispanic origin questions on the 2010 U.S. Census form, demonstrating how incongruities in design potentially harm people. This demonstrates a need for adding critical analyses to design and research and it refocuses the Society for Technical Communication’s value of promoting the public good on to design and documentation in order to fight injustice.     

Peer Teachers With Autism Teaching 3D Modeling

ABSTRACT

Few autism programmes address the needs of adolescents and young adults, and those that do are unlikely to include individuals with autism in the design and evaluation of the programme. This study involved nine youth with autism (ages 16–25) in the development and evaluation of a peer teaching programme where they taught three-dimensional modelling to other students with autism spectrum disorder. The methodology was participant-oriented research where the students with autism were co-designers and programme evaluators in the research. This approach highlighted their unique strengths and abilities and shifted the power such that they were leaders and not simply the recipients of knowledge from instructors. Four themes emerged through the qualitative analysis of the students’ perceptions of the peer teaching programme: 1) the meaning of peer teaching, 2) motivations for peer teaching, 3) challenges and 4) coping with the challenges of the role.