New curve sprint test for soccer players: Reliability and relationship with linear sprint     

Alberto Fílter  Jesús Olivares  Alfredo Santalla  Fabio Y. Nakamura  Irineu Loturco  Bernardo Requena 《Journal of sports sciences》2020,38(11-12):1320-1325

ABSTRACT

The speed performance is involved not only in linear sprints, but also in a wide spectrum of multi-directional movements, such as curve sprinting. Curved sprint can be defined as sprint with gradual and continuous change of direction (COD). Although ~85% of the actions performed at maximum velocity in a professional soccer league are curvilinear sprints, there is not any specific test to assess this ability. This study aimed to analyse the reliability of a new curve sprint test, and compare its results with those obtained by soccer players in linear sprint. Forty experienced soccer players performed 3 attempts of curve sprint (using the penalty arc) to right and left side (17 m), and 3 linear sprints (17 m) in two different days. The ICCs (inter-session reliability) were 0.93 for sprint curve right side (CSRS) and 0.89 for sprint curve left side (CSLS), considered “acceptable”. The CVs (intra-session reliability) were 0.87% in CSRS and 1.15% in CSLS. The coefficient of determination (R²) between linear and curve sprinting was ~35%. The association between curve sides was “very large” (r = 0.878; p < 0.01). In summary, we showed that “curve sprint test” is highly reliable, and that curvilinear and linear sprints are different and independent actions.  相似文献   

足球比赛的负荷量化-结构、方法和特征     

缪律  史国生  黎涌明 《成都体育学院学报》2020,(2):93-99,106

足球比赛负荷是球员在比赛情景下完成各类动作所承受的物理、生理和心理等方面刺激之和。比赛负荷的量化结构分为外部和内部负荷,外部负荷的量化方法包括人工视频分析技术、自动轨迹追踪技术和全球定位设备,通过球员体能或技术表现的负荷量和强度来评定足球比赛中的行为活动特点,外部负荷特征表现为间歇性运动下频繁变向和短距离变速跑,高比例的中低强度无球跑穿插较少的高强度带球跑。内部负荷的量化方法包括耗氧量、心率和血乳酸等指标的测定,通过上述指标的变化幅度来评定足球比赛中的能量代谢水平;内部负荷特征表现为有氧供能为主、无氧磷酸原和糖酵解供能交替进行。现有研究局限为外部负荷低估了变向运动对足球比赛负荷的影响,内部负荷无法概括正式比赛的供能特征等。未来可尝试在优化量化方法基础上结合内外负荷,从而更精准地量化比赛负荷。  相似文献   

Contextual factors on physical demands in professional women’s soccer: Female Athletes in Motion study     

Jason D. Vescovi  Olesya Falenchuk 《European Journal of Sport Science》2019,19(2):141-146

The aim of this study was to examine the impact of contextual factors on relative locomotor and metabolic power distances during professional female soccer matches. Twenty-eight players (forwards, n?=?4; midfielders, n?=?12; defenders, n?=?12) that competed in a 90-min home and away match (regular season only). The generalised estimating equations (GEE) was used to evaluate relative locomotor and metabolic power distances for three contextual factors: location (home vs. away), type of turf (natural vs. artificial), and match outcome (win, loss and draw). No differences were observed for home vs. away matches. Moderate-intensity running (20.0?±?1.0?m?min^?1 and 16.4?±?0.9?m?min^?1), high-intensity running (8.6?±?0.4?m?min^?1 and 7.3?±?0.4?m?min^?1) and high-metabolic power (16.3?±?0.5?m?min^?1 and 14.4?±?0.5?m?min^?1) distances were elevated on artificial turf compared to natural grass, respectively. Relative sprint distance was greater during losses compared with draws (4.3?±?0.4?m?min^?1 and 3.4?±?0.3?m?min^?1). Overall physical demands of professional women’s soccer were not impacted by match location. However, the elevation of moderate and high-intensity demands while playing on artificial turf may have implications on match preparations as well as recovery strategies.  相似文献   

Does performance justify the underrepresentation of women coaches? Evidence from professional women’s soccer     

《Sport Management Review》2019,22(5):640-651

In this paper, the authors empirically analyze the influence of the gender of the coach on team performance in women’s soccer leagues. Moreover, the authors examine the role of initial experience of coaches (as professional players) as an attribute that converges with gender diversity and influence performance. The sample includes the top divisions in France, Germany, and Norway from 2004 to 2017. The results from the regression model show that the gender of the coach is not a significant determinant of team performance (points per game). In addition, the initial experience of coaches does not alter the results. Therefore, managerial decisions of clubs with regard to the employment of coaches should not rely on gender.  相似文献   

A mathematical model for decision-making in the classification of para-footballers with different severity of coordination impairments     

Diego Pastor  María Campayo-Piernas  Jesús Tadeo Pastor 《Journal of sports sciences》2019,37(12):1403-1410

Classification is a defining feature of Para-sport, and sports-specific classification systems determined through multidisciplinary scientific research are required, i.e., evidence-based and focused on the relationship between the impairment and the key performance determinants. Data envelopment analysis (DEA) was applied as a classification tool using a directional distance function (DDF) model. The aim of the study was to test the DEA as a possible classification tool in cerebral palsy football. We analyse the performance of 56 international para-footballers with hypertonia, ataxia or athetosis, who completed a 20-test battery with DEA models. Five of the tests are included in the model (change of direction: Illinois agility test; jumping: standing broad jump, four bounds for distance, and triple hop with the non-dominant leg; 10-m sprint/acceleration; and ball dribbling, both in a straight line and following a trajectory), showing that players with less impairment exhibit the highest efficiency. This outcome suggests that DEA models might be feasible for detecting and discriminating the performance and magnitude of impairment in cerebral palsy football, with an objective ranking of the athletes in relation to different physical performance tests. This study also provides reference scores for decision-making during classification and guidance for further research in team Paralympic sports.  相似文献   

“三个转型”综合改革：新时代世界一流体育大学发展的历史选择     

曹卫东 《北京体育大学学报》2019,42(1):17-22

摘要：新时代是我国发展新的历史方位，体育强国、教育强国、健康中国三大战略为世界一流体育大学提出了新的更高要求。为此，北京体育大学提出了“三个转型”综合改革，以推进世界一流体育大学建设和高水平竞技体育后备人才培养基地建设，为国家培养勇担新时代体育事业发展重任的优秀人才。为实现上述目标，应在深刻认识“三个转型”改革提出的背景基础上，深入理解“三个转型”的内涵与目标，全面推进“三个转型”综合改革，为新时代体育、教育事业贡献北京体育大学的力量。研究背景包括：1）新时代是“三个转型”的历史坐标，2）强国战略是“三个转型”的现实依据，3）创新模式是“三个转型”的客观需要；“三个转型”分别是：1）全面推进从传统经验型体育大学向现代科技型体育大学转型，2）从以夏季项目为主的体育大学向夏季冬季项目全面发展的体育大学转型，3）从本土化体育大学向国际化体育大学转型，其目的是实现两大办学目标：1）把北京体育大学建成中国高水平竞技体育后备人才培养基地，2）把北京体育大学建设成为世界一流体育大学；为了实现“三个转型”转型及其目标，必须准确把握“办大学与建基地、文化传承与科技创新、立足中国与放眼世界”三个维度及其核心关键问题。  相似文献   

聚力探索特色小镇 开辟体产全新格局——北京大学第9届中国体育产业高峰论坛综述     

赵雯婷  丁怡清  封英  张锐 《北京体育大学学报》2019,42(2):95-102

摘要：习近平总书记在十九大报告中出要广泛开展全民健身活动，加快推进体育强国建设。随着“健康中国”上升为国家战略、居民消费升级需求日益加深，我国运动休闲特色小镇的发展路径显得尤为重要。在此背景下，专家学者和业界名流齐聚北京大学，集思广益、畅所欲言，为特色小镇献计献策，共商特色小镇建设合作大计。此次中国体育产业高峰论坛分论坛以“运动休闲特色小镇”为主题，对运动休闲特色小镇这个概念进行了全方位、系统性的深刻剖析，并结合运动休闲特色小镇相关成功实践经验，从前期策划、设计、投资到后期的建设、运营，再到内容为王、跨界融合、聚集建构效应，多层次、多角度阐释了运动休闲特色小镇建构的内在机理和方法，为建设运动休闲特色小镇事业，开创全新体育文化产业格局提供了切实可行的路径。  相似文献   

Understanding the topic evolution of scientific literatures like an evolving city: Using Google Word2Vec model and spatial autocorrelation analysis     

Kai Hu  Qing Luo  Kunlun Qi  Siluo Yang  Jin Mao  Xiaokang Fu  Jie Zheng  Huayi Wu  Ya Guo  Qibing Zhu 《Information processing & management》2019,56(4):1185-1203

Topic evolution has been described by many approaches from a macro level to a detail level, by extracting topic dynamics from text in literature and other media types. However, why the evolution happens is less studied. In this paper, we focus on whether and how the keyword semantics can invoke or affect the topic evolution. We assume that the semantic relatedness among the keywords can affect topic popularity during literature surveying and citing process, thus invoking evolution. However, the assumption is needed to be confirmed in an approach that fully considers the semantic interactions among topics. Traditional topic evolution analyses in scientometric domains cannot provide such support because of using limited semantic meanings. To address this problem, we apply the Google Word2Vec, a deep learning language model, to enhance the keywords with more complete semantic information. We further develop the semantic space as an urban geographic space. We analyze the topic evolution geographically using the measures of spatial autocorrelation, as if keywords are the changing lands in an evolving city. The keyword citations (keyword citation counts one when the paper containing this keyword obtains a citation) are used as an indicator of keyword popularity. Using the bibliographical datasets of the geographical natural hazard field, experimental results demonstrate that in some local areas, the popularity of keywords is affecting that of the surrounding keywords. However, there are no significant impacts on the evolution of all keywords. The spatial autocorrelation analysis identifies the interaction patterns (including High-High leading, High-Low suppressing) among the keywords in local areas. This approach can be regarded as an analyzing framework borrowed from geospatial modeling. Moreover, the prediction results in local areas are demonstrated to be more accurate if considering the spatial autocorrelations.  相似文献   

Evaluation of soccer players under the Moneyball concept     

Luiz Octávio Gavião  Annibal Parracho Sant’Anna  Gilson Brito Alves Lima  Pauli Adriano de Almada Garcia 《Journal of sports sciences》2020,38(11-12):1221-1247

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   

日本足球归化运动员的历史演进、运作逻辑与实践启示     

张大为  田胜国  刘兵 《沈阳体育学院学报》2020,(3):80-86,106

从历史演进视角对日本足球归化运动员进行研究,将归化演进历程分为业余足球主导期、职业足球改革探索期、职业足球稳定发展期3个阶段。归化运作逻辑体现:以技术足球理念为基准,合理实施归化行为;以填补位置短板为目的,提高国家队竞技水平;以保障职业角色转换为举措,营造良性发展氛围;以规避资源挤占矛盾为导向,逐步改变归化价值取向。启示:我国应厘清主体责任和发展理念,做好归化顶层设计;正视国家归化需求,消解文化融合与社会认同障碍;建立长效服务机制,扩大归化行为示范效应;把握足球运动规律,构建可持续发展模式。  相似文献