Specific muscular development in under‐18 soccer players     

Peter Leatt  Roy J. Shephard  Michael J. Plyley 《Journal of sports sciences》2013,31(2):165-175

A comparison of the under‐18 (U‐18) and under‐16 (U‐16) squads of the Canadian national soccer team with a representative sample of Canadians (Canada Fitness Survey, 1983) showed a tendency for the development or selection of the older players in teams of stature (U‐18, 175.8 cm; U‐16, 171.1 cm; CFS, 170.9 cm) and lean body mass (U‐18, 63.4; U‐16, 57.9; CFS, 54.2 kg). The larger lean mass of the older players could not be explained simply by size. The U‐18s also showed greater isokinetic leg extension force (particularly for rapid movements) and explosive strength (vertical jump) relative to the younger players, although the knee extension force was less than in some classes of athlete. Part of the gain in mass seems due to local training of the hip and leg muscles and part to a more general muscular development. Contrary to some reports, the hip flexibility of the Canadian players (sit and reach test) was greater than for a national sample; this may be important in avoiding soft tissue injuries to the legs. However, aerobic power (58.3±5.3 ml kg^‐1 min^‐1) and body fat (8.0±l.l%) were unremarkable.  相似文献   

The biomechanics of soccer: A review     

Robert S. Weinberg  Roy Chan  Allen Jackson 《Journal of sports sciences》2013,31(3):211-216

Abstract

The purpose of this investigation was to determine whether combining two mental preparation strategies would be more effective in enhancing performances than a single strategy. Subjects (n = 40) practiced on a basketball free throw task (20 shots) using one of the following mental preparation strategies: (a) imagery, (b) relaxation, (c) relaxation plus imagery, (d) placebo control. To simulate game conditions, subjects were allowed only 10 s in which to use their mental preparation strategy. After the practice session, subjects shot 20 test free throws using their designated technique. Results indicated a significant main effect with the imagery group performing significantly better than the placebo control group although there were no specific differences between the three experimental groups. The results are discussed in terms of potential variables mediating the effectiveness of imagery in enhancing sport performance, and future directions for research are offered.  相似文献   

American Association for Health,Physical Education,and Recreation     

Leon Garrett  Mohammed Sabie  Roy Pangle 《Research quarterly for exercise and sport》2013,84(4):496-498

Abstract

Utilizing canonical correlation analysis, the multivariate relationship between selected measures of motor performance and intellectual achievement was studied on 91 high school pupils. The students involved in the study were culturally deprived students who had been achieving well below their expected capacity. A significant relationship was found between the intellectual achievement domain and the motor performance domain. Also, significant relationships were found between the intellectual achievement domain and both of the sub-domains of fitness and coordination. The results in the present investigation were compared with the univariate analyses in a previous study. It was concluded that when the degree of relationship between two domains is desired, canonical correlation analysis may be of more value than the usual univariate procedures.  相似文献   

Modern Sport,Middle Classes and Globalization in the Post-War Caribbean 1945–1952: Variations on a Theme     

Roy McCree 《国际体育史杂志》2013,30(4):472-492

The study of the global diffusion of modern sport and the relationship between local and global processes has focused on their divergent, contested and cohesive character. Major criticisms of this study, however, include the lack of empirical and historical research, the neglect of the role of the imperial and other middle classes and a tendency to present globalization as a late-twentieth-century phenomenon driven by Americanization. By way of a regional case study of the Trinidad Amateur Athletic Association during the British colonial period 1945–1952, this paper examines (i) the varying effects of the globalization of sport through the spread of amateurism and professionalization; (ii) the role of the middle classes; (iii) the historical connection and disconnection between global and local processes; and (iv) the horizontal nature of the diffusion process, in order to counter the currently too dominant focus on vertical diffusion between first world and third world countries.  相似文献   

Family background variables as instruments for education in income regressions: A Bayesian analysis     

Lennart Hoogerheide  Joern H. Block  Roy Thurik 《Economics of Education Review》2012

The validity of family background variables instrumenting education in income regressions has been much criticized. In this paper, we use data from the 2004 German Socio-Economic Panel and Bayesian analysis to analyze to what degree violations of the strict validity assumption affect the estimation results. We show that, in case of moderate direct effects of the instrument on the dependent variable, the results do not deviate much from the benchmark case of no such effect (perfect validity of the instrument's exclusion restriction). In many cases, the size of the bias is smaller than the width of the 95% posterior interval for the effect of education on income. Thus, a violation of the strict validity assumption does not necessarily lead to results which are strongly different from those of the strict validity case. This finding provides confidence in the use of family background variables as instruments in income regressions.  相似文献   

Polydipsia and autoshaping: Drinking and leverpressing as substitutes for eating     

James Allison  Roy Mack 《Learning & behavior》1982,10(4):465-475

Three experiments delivered food at fixed or random intervals independently of the rat’s behavior, always less than the amount eaten with food freely available. The results revealed a Polydipsie response to this experimental suppression of eating, and total drinking decreased as total eating increased. When we added a lever that signaled each food delivery, leverpressing and drinking rose far above their baseline levels; both responses decreased as total eating increased. When a similar schedule presented lever and food independently, rats still became Polydipsie, but showed no sign of autoshaped leverpressing. A fourth experiment revealed a hypophagic response to schedules that suppressed drinking; total eating increased with total drinking. As mutual substitutes in the economic sense, one behavior falls as the other rises; as mutual complements in the economic sense, the two behaviors rise or fall together. We discuss polydipsia and autoshaping in terms of drinking as an intrinsic substitute for eating, and leverpressing as a learned substitute for eating. The results suggest a revision of conservation theory, which views drinking and eating as substitutes when the schedule suppresses eating but as complements when the schedule suppresses drinking.  相似文献   

The Educated Habitus, Progress at School, and Real Knowledge   总被引：1，自引：0，他引：1  

Roy Nash 《Interchange》2002,33(1):27-48

The New Zealand Progress at School study has demonstrated that certain personal dispositions, elements of the habitus, are associated with relative educational progress at school. The most important of these prove to be aspiration, academic self-concept, and perception of schooling. It is suggested, however, that these characteristics of the successful student are elements of the stratified self, unified by an overarching concept of education. Interview material with senior secondary school students is used to show how the desire to be educated within a specific concept of education is essential to their success. It is argued, with close reference to Bourdieu, that the concepts of education and the educated person need to be founded on the educational necessary as real knowledge.  相似文献   

Teacher Education,Evacuation and Community in War-Time Britain: The Women of Avery Hill at Huddersfield 1941–46     

Roy Fisher 《British Journal of Educational Studies》2019,67(1):77-96

The evacuation of civilians during Second World War Britain included the relocation not only of school children and teachers but of whole schools and, in some instances, of teacher training colleges. This paper examines the evacuation of Avery Hill College, a leading teacher training college, from London to Huddersfield between 1941 and 1946. Focusing on issues of gender and community, it provides an account of the circumstances of the move, institutional relations and resources, the social milieu of war-time Huddersfield, the challenges arising from evacuation, the responses of staff and trainees, and the broader institutional and teacher education policy transitions that ensued.  相似文献   

An Untimely Intuition: Adding a Bergsonian Dimension to Experience and Education   总被引：1，自引：0，他引：1  

Kaustuv Roy 《Educational theory》2005,55(4):443-459

This essay explores Henri Bergson's intuition as a philosophical and methodological concept, specifically considering how it might be useful in thinking about education. The main argument is that the repetition-succession model of time — or time as measure — that became established in modernity, and to which we are habituated, edits out of consciousness an organic, qualitative, nonhomogeneous aspect of time that is more true to our being-in-the world, resulting in an unfortunate thinning of our lives. An understanding of this different dimension of time, called duration here, awakens the intuition, making us less dependent on mechanical time, which is finitude, and more open to the nonmeasurable, qualitative aspects of phenomena. Pedagogically, this essay offers a praxis that aims toward a liberatory awakening to the conditions of our experience.  相似文献   

Modeling Student Cognition in Digital and Nondigital Assessment Environments     

Kristen E. DiCerbo  Yuning Xu  Roy Levy  Emily Lai  Laura Holland 《Educational Assessment》2017,22(4):275-297

Inferences about student knowledge, skills, and attributes based on digital activity still largely come from whether students ultimately get a correct result or not. However, the ability to collect activity stream data as individuals interact with digital environments provides information about students’ processes as they progress through learning activities. These data have the potential to yield information about student cognition if methods can be developed to identify and aggregate evidence from diverse data sources. This work demonstrates how data from multiple carefully designed activities aligned to a learning progression can be used to support inferences about students’ levels of understanding of the geometric measurement of area. The article demonstrates evidence identification and aggregation of activity stream data from two different digital activities, responses to traditional assessment items, and ratings based on observation of in-person non-digital activity aligned to a common learning progression using a Bayesian Network approach.  相似文献