Information-governing dynamics of attacker–defender interactions in youth rugby union     

Pedro Passos  Duarte Araújo  Keith Davids  Luis Gouveia  João Milho  SidóNio Serpa 《Journal of sports sciences》2013,31(13):1421-1429

Abstract

Previous work on dynamics of interpersonal interactions in 1 vs. 1 sub-phases of basketball has identified changes in interpersonal distance between an attacker and defender as a potential control parameter for influencing organizational states of attacker–defender dyads. Other studies have reported the constraining effect of relative velocity between an attacker and defender in 1 vs. 1 dyads. To evaluate the relationship between these candidate control parameters, we compared the impact of both interpersonal distance and relative velocity on the pattern-forming dynamics of attacker–defender dyads in the sport of rugby union. Results revealed that when interpersonal distance achieved a critical value of less than 4 m, and relative velocity values increased or were maintained above 1 m · s^?1, a successful outcome (i.e. clean attempt) for an attacker was predicted. Alternatively, when values of relative velocity suddenly decreased below this threshold, at the same critical value of interpersonal distance, a successful outcome for the defender was predicted. Data demonstrated how the coupling of these two potential, nested control parameters moved the dyadic system to phase transitions, characterized as a try or a tackle. Observations suggested that relative velocity increased its influence on the organization of attacker–defender dyads in rugby union over time as spatial proximity to the try line increased.  相似文献   

Prenatal programming of sporting success: Associations of digit ratio (2D:4D), a putative marker for prenatal androgen action,with world rankings in female fencers     

Raúl Bescós  Marc Esteve  Jordi Porta  Mercè Mateu  Alfredo Irurtia  Martin Voracek 《Journal of sports sciences》2013,31(6):625-632

Abstract

Associations of the second-to-fourth digit ratio (2D:4D), a putative marker for prenatal androgen action, and of absolute finger length, a putative marker for pubertal–adolescent androgen action, with sport performance were examined in a multinational sample of 87 world-class women épée fencers. Lower (masculinized) digit ratios correlated, although not significantly so, with better current and highest past world rankings. These correlations were significant for right-hand 2D:4D with controls for the most salient factors for 2D:4D (ethnicity) and world rankings (years of international experience, height, and weight). Longer (masculinized) fingers correlated strongly with better current and highest past world rankings; these correlations became insignificant with the same controls. Replicating previous evidence for fencers, left-handedness was much more prevalent in this sample (21%) than in the female general population, and left-handers had somewhat, but not significantly so, lower 2D:4D as well as better world rankings than right-handers. These findings extend related evidence suggestive of prenatal programming of aptitude across a variety of sports, especially running and soccer. Some known extragenital effects of prenatal testosterone that contribute to the development of efficient cardiovascular systems, good visuospatial abilities, physical endurance and speed, and to the propensity for rough-and-tumble play, apparently promote sporting success in adult life.  相似文献   

Jump higher,run faster: effects of diversified sport participation on talent identification and selection in youth basketball     

Jorge Arede  Pedro Esteves  António Paulo Ferreira  Jaime Sampaio  Nuno Leite 《Journal of sports sciences》2013,31(19):2220-2227

ABSTRACT

The aims of this study were to examine the medium-term effects of previous experiences during early stages of sport development on physical capacities of under-13 (U-13) talented basketball players and, to identify variables that discriminated under-14 (U-14) national team training camp selection. Anthropometrical and physical measurements were collected during a basketball training camp. Previous sport experiences (6–10 years), maturity offset, power outputs for jumping and sprinting were determined. A cluster analysis was used to allocate the subjects according to their different levels of sport experiences (more specialized vs. less specialized) to allow creating a dummy variable for the subsequent analysis of the physical variables. A stepwise discriminant analysis was computed to identify the construct that best classifies selected and non-selected players for U-14 national team training camp. The less specialized group outscored more specialized in all physical parameters, irrespectively of gender. The Abalakov Jump Peak Power and Predicted Adult Height (PAH) could successfully discriminate selected from non-selected players for U-14 national team training camp in boys and PAHin girls. The diversified and non-specific sport stimulus during early ages seem to be determinant to the acquisition and development of fundamental movement skills of talented basketball players.  相似文献   

The Development of Skill and Knowledge During a Sport Education Season of Track and Field Athletics     

Peter A. Hastie  Antonio Calderón  Ramiro J. Rolim  Anthony J. Guarino 《Research quarterly for exercise and sport》2013,84(3):336-344

Purpose: The purpose of this study was to examine the relative effectiveness of 2 forms of physical education instruction on students' skill and technical performance, as well as content knowledge in 3 track and field events. Method: Students from 6 classes in 3 Portuguese schools completed 900-min units conducted under the auspices of sport education or a more traditional teacher-directed format. Classes were randomly assigned to these conditions within each school. Results: Although both groups improved significantly from pretest to posttest, the sport education classes outperformed the traditional classes in both technique and skill execution. Only the sport education group made significant improvements in content knowledge. When the students in the traditional group were tested at the point in time where they would usually complete a unit of physical education (450 min), there were no significant improvements in any of the study's variables. Conclusion: The explanation given for the superior performance outcomes of the sport education classes lies in the nature of formal competition and team affiliation, which are cornerstones of this pedagogical model. That is, students take their learning experiences more seriously than in traditional and often inauthentic classes. In terms of content knowledge, the fact that sport education has a level of content-embedded accountability that holds students accountable for their officiating duties is postulated as a significant contributor to their increased understanding of rules and protocols of athletic events.  相似文献   

La fiesta de los toros. Un patrimonio compartido [The Toros Feast. A Shared Patrimony]     

Juan Rodríguez López 《国际体育史杂志》2013,30(12):1486-1488

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The effect of adolescents' sports clubs participation on self-reported mental and physical conditions and future expectations     

Thórdís Lilja Gísladóttir  Hafrún Kristjánsdóttir 《Journal of sports sciences》2013,31(10):1139-1145

Abstract

Sports clubs create conditions for people of all ages to pursue a healthy lifestyle through exercise in sports and attend to constructive pedagogical work which creates much value for society. This study investigates the relationship between adolescents' sports clubs participation and self-reported mental and physical conditions and future expectations. The participants were 10,987 pupils in the final three years of their compulsory education in Iceland (aged 14–16 years). The participants completed questionnaires administered to students in the classroom relating to health and behaviour. The results indicate that participation in sports clubs influences adolescents positively; adolescents who work hard at sport not only believe they are in better mental and physical condition, they also believe they can succeed in other areas such as their studies. Sports clubs promote positive influence on adolescents' mental and physical conditions and their future expectations toward work and happiness. It can be concluded that participation in organised sports clubs affects the participants in a positive way.  相似文献   

A Multidimensional Analysis of the Disability Digital Divide: Some Evidence for Internet Use     

María Rosalía Vicente  Ana Jesús López 《The Information Society》2013,29(1):48-64

Over the last few years, information and communication technologies have become an essential part of daily life, affecting education, employment, and leisure, among other activities. Nonetheless, many individuals still reap few or no benefits from these technologies, and there are resilient gaps in their use. Within this larger context, the authors examine the Internet digital divide between people with and without disabilities from a multidimensional approach. Rather than analyzing the gap in terms of “haves” and “have-nots,” a range of Internet-related dimensions—affordability, motivation and attitudes, skills, usage, and others—is taken into account.  相似文献   

Generalized multistable structure via chaotic synchronization and preservation of scrolls     

E. Jiménez-López  J.S. González Salas  L.J. Ontañón-García  E. Campos-Cantón  A.N. Pisarchik 《Journal of The Franklin Institute》2013,350(10):2853-2866

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The Teaching of the Mathematical Disciplines in Sixteenth-Century Spain*     

Víctor Navarro-Brotóns 《Science & Education》2006,15(2-4):209-233

This essay examines some aspects of the teaching of mathematics and its applications in three of the principal sixteenth century Spanish universities (Salamanca, Valencia and Alcalá) and in other institutions sponsored by the monarchy, such as the “Casa de la Contratación” (House of Trade) of Seville and the so-called Academy of Mathematics of Madrid. All three of the above universities had chairs of mathematics. In the Casa de la Contratación and other nautical schools the teaching of mathematics was oriented toward providing the foundations of navigation (nautical astronomy, instruments and maps, etc.). The Academy of Mathematics was oriented mainly towards subjects related to cosmography and navigation. Although the different areas of the teaching of mathematics imposed conditions on the discourses and practices of the mathematical disciplines, they did not impede the circulation of persons, knowledge, and practices among these areas. This work has partially financed by grants from Spanish Ministry of Science and Technology (BHA 2000–1456) and from Ministry of Education and Science (BHA2003-08394-(02-01).  相似文献   

Ethnocentrism in education: A comparative analysis of problems in Eastern and Western Europe     

Miklós Szabolcsi 《Prospects》1989,19(2):149-162

Professor of modern Hungarian Literature at Budapest University, 1965/66 visiting Professor at the Sorbonne, Paris, 1981–88 Director General of the Hungarian National Institute of Pedagogy. Since 1989, responsible for educational and cultural research. Author of several books in his fields of competence.  相似文献