Power training in elite young soccer players: Effects of using loads above or below the optimum power zone     

Irineu Loturco  Lucas A. Pereira  Valter P. Reis  Chris Bishop  Vinicius Zanetti  Pedro E. Alcaraz 《Journal of sports sciences》2020,38(11-12):1416-1422

ABSTRACT

This study aimed to examine the effects of two jump squat (JS) training programs involving different loading ranges in under-20 soccer players during a preseason period. Twenty-three elite young soccer players performed sprint speed (at 5-, 10-, and 20-m), change-of-direction (COD) speed, JS peak-power (PP), and countermovement jump (CMJ) tests pre and post four weeks of training. Athletes were pair-matched in two groups according to their optimum power loads (OPL) as follows: lower than OPL (LOPL; athletes who trained at a load 20% lower than the OPL) and higher than OPL (HOPL; athletes who trained at a load 20% higher than the OPL). Magnitude-based inferences were used to compare pre- and post-training measures. Meaningful increases in the PP JS were observed for both groups. Likely and possible improvements were observed in the 5- and 10-m sprint velocity in the LOPL group. Meanwhile, possible and likely improvements were observed in the CMJ, 5- and 10-m sprint velocity, and COD speed in the HOPL group. Overall, both training schemes induced positive changes in athletic performance. Soccer coaches and sport scientists can implement the JS OPL-based training schemes presented here, either separately or combined, to improve the physical performance of youth soccer players.  相似文献   

Acerca del hielo en el islam medieval     

Pedro Buendía 《Al-Masaq: Islam & the Medieval Mediterranean》2014,26(2):168-182

The history of ice in medieval Arab societies is obscured behind a mosaic of a variety of references and scholarly citations. Beyond al-Qalqashandī's reference to organised ice trafficking in fourteenth-century Mamluk Egypt, we do not have conclusive evidence on the origin and use of ice as a consumer product. In this paper we trace its presence based on three genres of references: historical and literary quotations, medicine and literature pertaining to food. These references allow us to consider the extent of ice consumption in the Arab world before the ninth century, as well as the existence of an organised trade throughout the Middle Ages from that time. However, contrary to the Persian world, with its well-documented Iranian yakhchals, we still know virtually nothing about ice-houses in medieval Arab societies. We also know very little about the profession of the thallāj or ice-seller, or whether the widespread consumption of ice that originated in Spain in the sixteenth century was in fact a legacy of an earlier trade in al-Andalus.  相似文献   

Reference power values for the jump squat exercise in elite athletes: A multicenter study     

Pedro L. Valenzuela  Michael McGuigan  Guillermo Sánchez-Martínez  Elaia Torrontegi  Javier Vázquez-Carrión  Zigor Montalvo 《Journal of sports sciences》2020,38(19):2273-2278

ABSTRACT

The present study aimed to provide reference values for lower-limb muscle power assessed during the incremental jump squat (JS) test in elite athletes (i.e., professional athletes competing at international level). We pooled data from all JS tests performed by elite athletes of different sports in two high-performance centres between 2015 and 2019, and computed reference values (i.e., terciles) for mean power (MP), mean propulsive power (MPP), and peak power (PP). Reference values were obtained from 684 elite athletes (458 male and 226 female) of 16 different sports (boxing, judo, karate, fencing, taekwondo, wrestling, basketball, soccer, futsal, handball, rugby union, badminton, tennis, long distance running, triathlon, and sprinting). Significant differences (p < 0.001) were found between male and female athletes for MP (7.47 ± 1.93 and 6.15 ± 1.68 W·Kg^?1, respectively), MPP (10.50 ± 2.75 and 8.63 ± 2.43 W·Kg^?1), and PP (23.64 ± 6.12 and 19.35 ± 5.49 W·Kg^?1). However, the velocity at which these power measures was attained seemed to be independent of sex (~0.95, 1.00 and 2.00 m·s^?1 for mean, mean propulsive, and peak velocity, respectively) and homogeneous across different sport disciplines (coefficient of variation <10%). These data can be used to classify athletes’ power capabilities, and the optimum velocity ranges provided here could be useful for training purposes.  相似文献   

Child labour and educational success in Portugal     

Pedro Goulart  Arjun S. Bedi   《Economics of Education Review》2008,27(5):575-587

The current debate on child labour focuses on developing countries. However, Portugal is an example of a relatively developed country where child labour is still a matter of concern as between 8% and 12% of Portuguese children may be classified as workers. This paper studies the patterns of child labour in Portugal and assesses the consequences of working on the educational success of Portuguese children. The analysis controls for typically unobserved attributes such as a child's interest in school and educational ambitions and uses geographical variation in policies designed to tackle child labour and in labour inspection regimes to instrument child labour. We find that economic work hinders educational success, while domestic work does not appear to be harmful. Furthermore, after controlling for a host of socio-economic variables, factors such as a child's interest in school and educational ambitions have a large effect on boosting educational success and reducing economic work.  相似文献   

Introduction to “Racial Inequality and Education: Patterns and Prospects for the Future”     

Pedro A. Noguera 《The Educational forum》2017,81(2):129-135

Abstract

American society is in the midst of profound economic and demographic changes. At the same time that the racial and ethnic composition of American society is changing, disparities in income and wealth have grown wider and more pronounced than ever before. This article explores the ways in which race is implicated in the widening gaps in wealth and opportunity, and how these inequities impact educational achievement.  相似文献   

Mental attention in gifted and nongifted children     

Jose I. Navarro  Pedro Ramiro  Jose M. Lopez  Manuel Aguilar  Manuel Acosta  Juan Montero 《European Journal of Psychology of Education - EJPE》2006,21(4):401-411

The relationship between the construct of mental attention and “giftedness” is not well established. Gifted individuals could make effective use of their executive functions and this could be related to their mental attentional capacity. The dialectic constructivist model developed by Pascual-Leone introduced the concept of mental attention or “effort”, relating it to mental capacity. The aim of this study is to investigate whether the measurement of mental capacity (M-measurement) is differential for a group of children with high IQs. 110 students between 4 and 18 years old participated in this study. Some were Gifted (n=70) and others Non-Gifted (n=40). Wechsler-R Scale and the Figural Intersection Test were administered to all participants. An interesting pattern was found in the younger groups. The gifted scored higher than the non-gifted in the Figural Intersection Test and much higher than their theoretical M. The non-gifted scored quite close to their theoretical M (based on age). In the oldest group, the gifted again achieved higher scores, but now they scored at the theoretical level, and the non-gifted underperformed.  相似文献   

Going to action? A literature review on educational proposals in formal Environmental Education     

Mercedes Varela-Losada  Pedro Vega-Marcote  Uxío Pérez-Rodríguez  María Álvarez-Lires 《Environmental Education Research》2016,22(3):390-421

The current state of the planet’s environmental deterioration calls for formal educational contexts to implement effective environmental proposals which nurture action competence. The aim of this paper is to examine the educational proposals in formal contexts that have been published in the two research journals of greatest impact on Environmental Education during the period 2008–2013, and to analyse how they contribute to the development of action competence. Special attention is paid to research (i) based on real participation by students; (ii) promotes reflection on the complexity of environmental issues; (iii) facilitates critical thinking; (iv) encourages autonomous and responsible decision-making and (v) involves communities. Our results show that these approaches can help improve the development of action-focused environmental education and bring to light a series of challenges for future research.  相似文献   

Creating Respectful Classroom Environments   总被引：1，自引：0，他引：1  

Regina Miller  Joan Pedro 《Early Childhood Education Journal》2006,33(5):293-299

Creating respectful classroom environments Respect is a critical variable in education. It is critical to each individual child in the classroom environment as well as to the teaching and learning that takes place in the classroom. Children learn by example. Where do they get their examples? This article explores the parameters of teaching and encouraging respect in classrooms for young children. Emphasis is placed on the creation of respectful classroom environments taught by teachers who have themselves been prepared to nurture this kind of environment.  相似文献   

Monitoring the ‘Enlaces’ educational computer network     

Pedro Hepp  Ernesto Laval  Gerardo Moënne  Miguel Ripoll 《Education and Information Technologies》1996,1(1):5-20

The use of networks in education is experiencing world-wide growth. Many schools have taken advantage of the reduction of price in modems, the emergence of electronic bulletin boards and world-wide web pages with educational content, and the availability of software for public participation in networks. Nevertheless, little information is available about the quality and quantity of existing network traffic; information that would allow organizations, network project administrators and supporters, to evaluate its impact, know its usage, evolution and projections. This paper presents some of the traffic monitoring mechanisms presently in use in a Chilean educational network (the Enlaces Project), together with examples of the information collected through these mechanisms.  相似文献   

Higher education and its contribution to a diverse regional supply of human capital: does the binary/unitary divide matters?     

Artur Santoalha  Ricardo Biscaia  Pedro Teixeira 《Higher Education》2018,75(2):209-230

Diversity has been an important topic of research for some time in higher education, though the purposes underlying this attention have varied across national and regional contexts. In many parts of the world, the term diversity has been emphasized with regard to variety among the programs or services provided by academic institutions, and differences among the types of institutions themselves. It is particularly important to discuss whether different dimensions of diversity may influence the degree of effectiveness of higher education (HE) in fulfilling its contribution and relevance to economic and social development. We are particularly interested in analyzing whether unitary or binary systems present significant differences in different dimensions of diversity that may be relevant to enhance higher education institutions’ (HEIs) contribution to territorial cohesion, notably by enhancing the local stock of human capital and contributing to the social and cultural development of their regions. Therefore, we propose the following research questions: *Are there relevant patterns regarding different dimensions of diversity between unitary and binary HE systems? *In the case of binary systems, is it possible to find relevant differences in different dimensions of diversity between universities and more vocational HEIs? By looking at these questions, we aim at contributing both to the literature on HE institutional diversity and to the study of the role played by HEIs on regional development.  相似文献