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51.
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   
52.
Abstract

Although it is acknowledged that appropriate breast support during exercise is important, no published literature has assessed breast support usage in a cohort of female marathon runners. This study aimed to identify sport bra use and perceived importance of sports bra use in female marathon runners. Bra satisfaction, incidence of bra related issues and factors that influence the appropriateness of sports bras were also investigated. A 4-part, 30-question survey was administered to 1397 female runners at the 2012 London marathon registration and via an online survey. In total 1285 surveys were completed. Sports bra use and its perceived importance was high, however was lower in moderate compared to vigorous activity, and lower in participants with smaller breasts. Seventy-five per cent of participants reported bra fit issues. The most common issues were chaffing and shoulder straps digging in, with a higher incidence of issues reported by participants with larger breasts. Use of professional bra fitting was low, and perceived knowledge of breast health was poor. Engagement with sports bra use is high although sports bra design could be improved to alleviate bra fit issues experienced by female runners. Educational initiatives are needed to ensure females are informed regarding the importance of breast support and appropriate bra fit during activity.  相似文献   
53.
Abstract

The relationship between date of birth and success in a variety of sports, including hockey, is well established. This phenomenon is known as the relative age effect (RAE). We model the RAE in Canadian youth hockey as a positive feedback loop where an initial age advantage is reinforced through additional training and playing opportunities based on perceived skill superiority. The same causal mechanism leads to a higher quit rate for relatively younger players. Our model effectively replicates the birth month distribution of Canadian National Hockey League players (R2 = 86.79%) when driven by Canadian birth distributions. We use this model to evaluate three policies that aim to lessen the RAE. All of the policies reduce the RAE with a significant delay. The most effective policy is a combination of providing additional support to age disadvantaged children and rotating the cut-off date for youth leagues between January 1st and July 1st annually. In equilibrium, this approach leads to a 96% reduction in the RAE compared to the base case.  相似文献   
54.
ABSTRACT

Selecting effective dietary strategies for professional football players requires comprehensive information on their energy expenditure (EE) and dietary intake. This observational study aimed to assess EE and dietary intake over a 14-day period in a representative group (n = 41) of professional football players playing in the Dutch Premier League (Eredivisie). Daily EE, as assessed by doubly labelled water, was 13.8 ± 1.5 MJ/day, representing a physical activity level (PAL) of 1.75 ± 0.13. Weighted mean energy intake (EI), as assessed by three face-to-face 24-h recalls, was 11.1 ± 2.9 MJ/day, indicating 18 ± 15% underreporting of EI. Daily EI was higher on match days (13.1 ± 4.1 MJ) compared with training (11.1 ± 3.4 MJ; P < 0.01) and rest days (10.5 ± 3.1 MJ; P < 0.001). Daily carbohydrate intake was significantly higher during match days (5.1 ± 1.7 g/kg body mass (BM)) compared with training (3.9 ± 1.5 g/kg BM; P < 0.001) and rest days (3.7 ± 1.4 g/kg BM; P < 0.001). Weighted mean protein intake was 1.7 ± 0.5 g/kg BM. Daytime distribution of protein intake was skewed, with lowest intakes at breakfast and highest at dinner. In conclusion, daily EE and PAL of professional football players are modest. Daily carbohydrate intake should be increased to maximize performance and recovery. Daily protein intake seems more than adequate, but could be distributed more evenly throughout the day.  相似文献   
55.
ABSTRACT

Although the talent development environment and mental toughness are critical for athletes to realise their athletic potential, there is a dearth of literature on whether the talent development environment can enhance mental toughness among those athletes who are identified with athletic potential (i.e., talented athletes). Drawing on self-determination theory (Deci & Ryan, 2000), this research examined the relationships between the talent development environment, basic psychological needs satisfaction and mental toughness. Talented athletes (n = 261) completed a survey measuring key features of the talent development environment, needs satisfaction and mental toughness. The results of structural equation modelling indicated that three environmental factors (i.e., long-term development focus, holistic quality preparation and communication) were positive predictors of needs satisfaction, which then positively predicted mental toughness. The talent development environment may be considered for promoting talented athletes’ mental toughness.  相似文献   
56.
ABSTRACT

The aim of this study was to systematically review the literature to verify the association between participation in sports (PS) in childhood and adolescence and physical activity (PA) in adulthood. A systematic search was conducted in the following databases: Medline (PUBMED), Web of Science, Scopus, and SPORTDiscus, LILACS and SciELO. All steps of the process followed the recommendations of the PRISMA FlowDiagram. After all the steps of the process, 29 articles were included for analysis. In general, only three of the studies analyzed found no relation between PS in childhood and adolescence and PA in adulthood. However, a positive relationship was found to be weak in only 7% of the studies, a moderate relation in 62% of the studies, and a strong relation in 21%. It was found that higher weekly frequencies of PS; persistence of at least three years of PS and, finally, the highest level of practice and/or competition reached were related to higher levels of PA in adulthood. Thus, it can be concluded that there is a positive association considered moderate to strong between PS in childhood and adolescence and PA in adulthood.  相似文献   
57.
Abstract

The purpose of this study was to assess the potential influence of birth quarter on the frequency of physical activity and participation in specific activities during adulthood. We used data from one national and one provincial survey, the 2005 Canadian Community Health Survey and the 1998 Quebec Social and Health Survey (Enquête sociale et de santé du Québec) respectively. We analysed the distribution of participants at each level of practice of a given leisure activity and work-related physical activity. In the Canadian Community Health Survey, a relative age effect was found for participation in soccer in the 25- to 60-year-old population. However, for volleyball, a significant relative age effect was also observed but with over-representation of the last quarters of the year for the whole population and for men aged 12–60 years. In the Quebec Social and Health Survey, significant differences in the frequency of distribution without a relative age effect were revealed for participation in women's ice hockey, work-related physical activity level, and stage of change for physical activity. Overall, the data indicate that the systematic relative age effect reported in other studies for some competitive sports, such as ice hockey and soccer, is not as prevalent in leisure physical activities during adulthood. This may reflect lower competitive selection and attrition in population physical activity compared with competitive sports in younger athletes.  相似文献   
58.
Abstract

Research has shown that talented athletes outscore their mainstream peers on the basis of self-regulation. Although valuable, this does not tell us more about the distinction between good athletes and the best, which is a prerequisite in talent development. Therefore, we examined the self-regulatory skills of 222 male and female talented athletes aged 12–16 years as a function of competitive sport level (junior international or junior national athletes) and type of sport (individual or team sports). Multivariate analyses of covariance in combination with a discriminant function analysis revealed that “reflection” distinguishes between athletes at the highest levels of excellence. Furthermore, athletes playing individual sports had higher scores on “planning” and “effort” than team sport athletes, highlighting the importance of differences between types of sport. In conclusion, we emphasize the importance of reflection as a self-regulatory skill. Reflection facilitates the development of sport-specific characteristics, which may vary by type of sport. This means that an advanced sense of reflection may help talented athletes to acquire desirable characteristics during their “talent” years to ultimately reach adult elite levels of competition.  相似文献   
59.
Abstract

We quantify the nature and frequency of anticipation behaviours in professional tennis using video coding of incidents where the time delay between the opponent's stroke and the reaction of the player were recorded. We argue that anticipation is based on uncertain information and should lead in some situations to erroneous decisions. We identified the transition between reaction (with 100% accuracy in the selection of where the ball is played on the court) and anticipation (with less than 100% accuracy) as being 140–160 ms after ball contact. Anticipation behaviours occurred on between 6.14% and 13.42% of the coded situations. These anticipation behaviours appeared almost exclusively in ‘unfavourable’ situations, where the opponent had a significant tactical advantage, with the type of playing surface having only a limited effect. Moreover, the decrease in accuracy with shorter response times is not monotonic, with an increase in response accuracy being observed for times shorter than 120 ms before ball contact. We propose that very early anticipation behaviours occur when players use significant context-specific information before the opponent's stroke. When such information is not available, players produce anticipation behaviours that are closer to the moment of ball–racket contact using information that is more likely to be based on the opponent's preparation of the stroke. This study opens new directions for research focusing on the testing and training of anticipation in fast ball sports.  相似文献   
60.
This article studies similarities and disparities between the two nations England and Norway as they could be observed before and during the London 2012 Olympics, and discuss them in the historical perspective of geopolitical and sportive relations. The main perspective is how these relations have been seen and experienced from Norway. The article also studies whether the London Olympics of 2012 did present new forms of relationships between the two geographical neighbours. The article discusses the role of ball games, preferably team handball at the 2012 Games, as one example of where sporting interests differ. The article reflects upon these matters in a historical context. It builds upon traditional historical methods, document and media analysis. It also looks at the 2012 London Olympics against the background of the former London Games of 1908 and 1948, and the overall historical sports relations between England, ‘land of sport’ and a small country like Norway, who generally has been on the receiving end of these interchanges. Such asymmetric relationships invite to a critical use of perspectives like cultural imperialism and post-colonialism. The article discusses whether such perspectives can be fruitful also when one discusses matters between the so-called First World nations. As the title of the article indicates, Norway and England are both close, politically and culturally, while also being strangers to one another, e.g. in parts of the sports culture. The 2012 Olympics seemed to reinforce this impression.  相似文献   
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