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1.
This study empirically examines the effect of child labor on academic achievement in 10 francophone Western and Central African countries. The data were taken from the Programme d’Analyse des Systèmes Educatifs de la CONFEMEN and comprised characteristics of 25,288 grade six students across 1803 schools. Two-stage least squares analysis highlights that child labor undermines academic achievement regardless of subject, gender, and age. It lowers reading and mathematics scores for both genders and for children under 12 and over 13 years. Child labor therefore hinders human capital accumulation in African countries, and it takes place at the cost of future prosperity.  相似文献   
2.
ABSTRACT

Despite emotional, technical and endurance implications for athletes’ performance, a consensus has yet to be reached to explain the impairment of executive functioning during exercise. In particular, recent research challenges the original assumption of a linear dose–response effect of exercise intensity on cerebral physiology and executive functioning. We propose a fatigue-based neurocognitive perspective of executive functioning during prolonged exercise, suggesting that top-down (cognitive and physical efforts) and bottom-up processes (body sensations) act in parallel of arousing mechanisms to determine cognitive outcomes. In this perspective, executive functioning during prolonged exercise would be dynamical rather than steady (i.e. positively then negatively impacted by exercise) and would be to analyse in regards of exercise termination rather than of exercise intensity.  相似文献   
3.
ABSTRACT

Adaptive regulation of emotions is imperative for successful sport performance. However, the lion’s share of mainstream emotion regulation (ER) literature is founded on perspectives prioritising mental health, not performance. Consequently, ER strategies are predominantly classified as adaptive or maladaptive based on effectiveness in achieving targeted mental health outcomes. These conventional mental health classifications can catalyse misapplication of ER strategies within sport and other motor performance contexts when (1) ER motives are instrumentally directed towards performance enhancement and (2) Minimal consideration is given to the consequences of ER on the coordination and execution of motor actions. Herein, we review the current state of relevant ER research within and outside of sport contexts. We also present a novel conceptual framework, the Temporal Influence Model of Emotion Regulation (TIMER). TIMER proposes that ER strategies exert distinct, temporally dependent demands upon perceptual-cognitive and motoric resources. These unique regulatory profiles influence subsequent motor performance outcomes. Critically, the degree to which regulatory strategies are appropriate or ideal varies given environmental constraints along with performers’ affective and performance goals. The model includes testable hypotheses to guide theoretical and applied research in the domain of ER within sport and other motor performance contexts.  相似文献   
4.
胡胜 《当代体育科技》2020,(12):51-51,53
本文通过综述几种常见的力量功能训练方法,为提高运动训练成绩和大众体质健康健身服务。近年来,力量训练方法越来越多,有速度力量和耐力力量训练。常见的力量训练功能训练有振动训练、PNF训练、悬吊训练、超等长训练、本体感觉与核心训练。力量训练通常与速度、敏捷、耐力和反应训练密切相关,适时加强与力量有关的素质练习尤为重要,只有这样才能提高力量训练的效果,保持运动成绩,以力量为基础的功能训练衍生出来多种训练方法,本文对这些方法梳理和总结,为后人研究学习提供方便。  相似文献   
5.
2019年国际篮联篮球世界杯在中国圆满举行,广州作为分赛场,承接了西班牙、波多黎各、突尼斯以及伊朗四支代表队的小组比赛6场。通过对广州赛区四支队伍在小组赛中的表现技术进行分析,并对比中国队在本次赛事中的表现,发现中国男篮在备赛与参赛阶段,存在大赛目标不清晰,心理训练与细节训练不足,教练团队执教水平不稳定,篮球基本功不扎实等一系列问题,反映出我国篮球的发展正处于困境。系统地分析广州小组赛中四支队伍的赛况,并与中国队做出对比,有针对性地提出建议,为中国篮球的发展提供参考。  相似文献   
6.
ABSTRACT

The recruitment of athletes with limited resources is a global problem in professional sports. In US Major League Baseball, the experience of the Oakland Athletics’ general manager in the last decade turned his “Moneyball” model into a synonym of quantitative analysis in the transfer market of baseball players. His strategy focused on hiring players with outstanding technical skills but relatively low market value. This study adapted this model to the framework of a multiple criteria decision aid (MCDA), by selecting undervalued players who have complementary abilities. The novelty here refers to the joint use of four algorithms explored by the composition of probabilistic preferences (CPP) (i.e., ranking, classification, dynamic evaluation and regularity analysis) and their application to soccer player performance evaluation. The new model analysed the recent transfer of a left-back soccer player to Europe. The results indicated 12 opportunities for better investment, among 32 left and right-back players considered. Two years later, the value of the same player was considerably lower. He played only five matches in the 2018–2019 season, without scoring or providing any assists. On the other hand, the players better classified by the CPP-MB model presented higher performances and market values.  相似文献   
7.
ABSTRACT

Participation in youth sport is positively associated with physical fitness and performance. The purpose of the current study was to examine if physical fitness measures during childhood and early adolescence predicted high school sport participation. Participants included youth in the Michigan State University Motor Performance Study. Measures consisted of the endurance shuttle run, Wells sit-and-reach, jump and reach, standing long jump, agility shuttle run and 30-yard dash. Individual, generalized estimating equation models were used to estimate the association between each measure and the odds of participating in high school sport. For both sexes, the endurance shuttle run and agility shuttle run were related to sport participation. For boys only, the long jump and 30-yard dash were also associated with sport participation. Better physical fitness and performance across several dimensions in childhood, including those related to motor skills, enhanced the likelihood of sport participation in high school.  相似文献   
8.
ABSTRACT

Meta-analytic evidence supports that exercise has benefits for short-term memory (STM) and long-term memory (LTM). However, only three studies with children have tested the differential effects of exercise on STM and LTM. The purpose of this study was to examine the effects of an aerobic fitness test on STM and LTM and to consider the moderating effects of grade level. Children (7–13 years of age) were randomly assigned to either perform an aerobic fitness test before (exercise prior) or after (exercise post) performing the Rey Auditory Verbal Learning Test (RAVLT) to assess memory. Memory was tested again after approximately 24 hours. There were significant differences in memory performance as a function of grade with 4th and 6th graders consistently outperforming 2nd graders. For learning, Day 1 Retention, 24-hr recall, and Day 2 Retention, the exercise prior group performed better than the exercise post group. It is concluded that an aerobic fitness test performed prior to a declarative memory test benefits LTM as compared to when the aerobic fitness test is performed after the memory test.  相似文献   
9.
采用计算流体动力学的方法,利用STAR-CCM+软件对某一车型挡风玻璃除霜性能进行数值模拟分析。通过对出风口格栅进行调整,改变了暖风气流与挡风玻璃之间碰撞角的大小与碰撞点的位置,优化了挡风玻璃表面暖风气流的分布,提升了除霜性能,为汽车除霜风道的设计和改善车辆除霜性能提供了参考。  相似文献   
10.
ABSTRACT

The aim of this study was to assess if tactical and technical performance indicators (PIs) could be used in combination to model match outcomes in Australian Football (AF). A database of 101 technical PIs and 14 tactical PIs from every match in the 2009–2016 Australian Football League (AFL) seasons was merged. Two outcome measures Win-loss and Score margin were used as dependent variables. The top 45 ranked technical and tactical PIs from a feature selection process were used to model match outcome using decision tree and Generalised Linear Models (GLMs). Of the top 45 selected features, this included seven tactical PIs. The Win-loss-based Decision tree model achieved a classification accuracy of 89.0% and GLM 93.2%. A Score margin-based GLM achieved a root mean squared error (RMSE) of 6.9 points. A combined approach to the classification of match outcomes provided no improvement in model accuracy compared with previous literature. However, this study has established the relative importance of technical and tactical measures of performance in relation to successful team performance in AF.  相似文献   
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