Association of different types of playing surfaces with bone mass in growing girls     

Esther Ubago-Guisado  Jorge García-Unanue  Jorge López-Fernández  Javier Sánchez-Sánchez  Leonor Gallardo 《Journal of sports sciences》2017,35(15):1484-1492

The aim of this cross-sectional study was to compare bone mass in young female athletes playing ball games on different types of playing surfaces. About 120 girls, 9–13 years of age (10.6 ± 1.5 years old Tanner I–III) were recruited and divided into prepubertal and pubertal groups. The sample represented 3 groups of athletes: soccer (N = 40), basketball (N = 40), and handball (N = 40); and 6 different playing surfaces (soccer – ground, soccer – artificial turf, basketball – synthetic, basketball – parquet, handball – synthetic, and handball – smooth concrete). Total and regional body composition (bone mass, fat mass, and lean mass) were measured by dual-energy X-ray absorptiometry (DXA). The mechanical properties of the surfaces (force reduction, vertical deformation, and energy return) were measured with the Advanced Artificial Athlete (Triple A) method. The degree of sexual development was determined using Tanner test. The pubertal group showed that soccer players on the ground, basketball players on synthetic, and handball players on smooth concrete had higher values of bone mineral content (BMC) and bone mineral density (BMD) (P < 0.05) than the soccer players on the artificial turf, basketball players on parquet, and handball players on synthetic. In conclusion, a hard playing surface, with less vertical deformation and force reduction, and greater energy return, is associated with higher levels of BMD and BMC in growing girls, regardless of the sport they practice.  相似文献   

Advancing our understanding of understanding     

Xavier de Donato Rodríguez 《Metascience》2015,24(3):497-502

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Editorial     

Erik de Graaff 《European Journal of Engineering Education》2011,36(1):1-2

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Educational leadership and pupil achievement in primary education     

W. van de Grift  A.A.M. Houtveen 《School Effectiveness & School Improvement》2013,24(4):373-389

Educational leadership can be defined as the ability of a principal to initiate school improvement, to create a learning-oriented educational climate, and to stimulate and supervise teachers in such a way that the latter may execute their tasks as effectively as possible. In 1989, 1993, and 1998, teacher perceptions of educational leadership of principals in Dutch elementary education were evaluated by means of a Rasch-scale. It turned out that the educational leadership of Dutch principals has grown considerably. In both 1989 and 1993 the effect of educational leadership on pupil achievement was investigated. While in 1989 no significant relationship was found, the results of 1993 show a significant relationship between educational leadership and average pupil achievement over 3 successive years corrected for school environment.  相似文献   

Quantifying the offensive sequences that result in goals in elite futsal matches     

Hugo Sarmento  Paul Bradley  M. Teresa Anguera  Tiago Polido  Rui Resende  Jorge Campaniço 《Journal of sports sciences》2016,34(7):621-629

The aim of this study was to quantify the type of offensive sequences that result in goals in elite futsal. Thirty competitive games in the Spanish Primera Division de Sala were analysed using computerised notation analysis for patterns of play that resulted in goals. More goals were scored in positional attack (42%) and from set pieces (27%) compared to other activities. The number of defence to offense “transitions” (n = 45) and the start of offensive plays due to the rules of the game (n = 45) were the most common type of sequences that resulted in goals compared to other patterns of play. The central offensive zonal areas were the most common for shots on goal, with 73% of all goals scored from these areas of the pitch compared to defensive and wide zones. The foot was the main part of the body involved in scoring (n = 114). T-pattern analysis of offensive sequences revealed regular patterns of play, which are common in goal scoring opportunities in futsal and are typical movement patterns in this sport. The data demonstrate common offensive sequences and movement patterns related to goals in elite futsal and this could provide important information for the development of physical and technical training drills that replicate important game situations.  相似文献   

Rating of perceived exertion in maximal incremental tests during head-out water-based aerobic exercises     

Cristine Lima Alberton  Stephanie Santana Pinto  Tatiane Gorski  Amanda Haberland Antunes  Paula Finatto  Eduardo Lusa Cadore 《Journal of sports sciences》2016,34(18):1691-1698

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Olympics,Media and Politics: The First Olympic Ideas in Brazilian Society During the Late Nineteenth and Early Twentieth Centuries     

Fabio de Faria Peres  Victor Andrade de Melo 《国际体育史杂志》2016,33(12):1380-1394

Abstract

The Olympic Games of the modern era are powerful global mediated events. Olympic cities receive an overwhelming examination by world media. As the 2016 Olympic host, Rio de Janeiro has been given an enormous amount of attention, both by the international media and researchers who looked at the urban spaces of Rio, the struggles over the hegemony of the city and the social meanings the Olympics bring to the host city’s citizens. However, studies over the historical relationship between Rio, sport and media are rare. This paper addresses the historical uses of the term Olympic by Brazilian media during the late nineteenth and the early twentieth centuries. By looking at the main articles in the newspapers of these periods, we examine the extent to which ideologies over sports have changed the way the Olympics were represented in Brazil’s national imaginary. We demonstrate how the use of expressions associated with the Olympics historically generated a closer appreciation of these events by the public. We also show how political authorities appropriated the Olympics for their own benefit. The paper concludes by asking whether or not the historical lessons from the early Olympic ideas in Brazil have been learned by the 2016 Rio Games organizers.  相似文献   

学风建设深层问题的几点思考   总被引：5，自引：0，他引：5  

王宝德 《煤炭高等教育》2003,21(5):49-51

高校学风建设要以学生为中心，一切从学生的根本利益出发，对学生全面负责。通过深化教育教学改革，充分调动学生学习的积极性、主动性、创造性并培养学生优良的道德品质是学风建设的根本目的。  相似文献   

Perceived health problems in swimmers according to the chemical treatment of water in swimming pools     

Álvaro Fernández-Luna  Pablo Burillo  José Luis Felipe  Julio del Corral  Jorge García-Unanue  Leonor Gallardo 《European Journal of Sport Science》2016,16(2):256-265

The objective of this study was to determine which chemical treatment used for disinfecting water in indoor swimming pools had the least impact on users' perceptions of health problems, and which generated the greatest satisfaction with the quality of the water. A survey on satisfaction and perceived health problems was given to 1001 users at 20 indoor swimming pools which used different water treatment methods [chlorine, bromine, ozone, ultraviolet lamps (UV) and salt electrolysis]. The findings suggest that there is a greater probability of perceived health problems, such as eye and skin irritation, respiratory problems and skin dryness, in swimming pools treated with chlorine than in swimming pools using other chemical treatment methods. Pools treated with bromine have similar, although slightly better, results. Other factors, such as age, gender, time of day of use (morning and afternoon) and type of user (competitive and recreational), can also affect the probability of suffering health problems. For all of the above, using combined treatment methods as ozone and UV, or salt electrolysis produces a lower probability of perceived health problems and greater satisfaction.  相似文献   

Measurement precision of body composition variables in elite wheelchair athletes,using dual-energy X-ray absorptiometry     

Mhairi Keil  Julia O. Totosy de Zepetnek  Katherine Brooke-Wavell 《European Journal of Sport Science》2016,16(1):65-71

The purpose of this study was to assess the reproducibility of body composition measurements by dual-energy X-ray absorptiometry (DXA) in 12 elite male wheelchair basketball players (age 31 ± 7 years, BMI 21 ± 2 kg/m² and onset of disability 25 ± 9 years). Two whole body scans were performed on each participant in the supine position on the same day, using Lunar Prodigy Advance DXA (GE Lunar, Madison, WI, USA). Participants dismounted from the scanning table and were repositioned in-between the first and second scan. Whole body coefficient of variation (CV) values for bone mineral content (BMC), fat mass (FM) and soft tissue lean mass (LTM) were all <2.0%. With the exclusion of arm FM (CV = 7.8%), CV values ranged from 0.1 to 3.7% for all total body and segmental measurements of BMC, FM and LTM. The least significant change that can be attributed to the effect of treatment intervention in an individual is 1.0 kg, 1.1 kg, 0.12 kg for FM, LTM, and BMC, respectively. This information can be used to determine meaningful changes in body composition when assessed using the same methods longitudinally. Whilst there may be challenges in the correct positioning of an individual with disability that can introduce greater measurement error, DXA is a highly reproducible technique in the estimation of total and regional body composition of elite wheelchair basketball athletes.  相似文献