Comparing the magnitude and direction of asymmetry during the squat,countermovement and drop jump tests in elite youth female soccer players     

Chris Bishop  Lucas A. Pereira  Valter P. Reis  Paul Read  Anthony N. Turner  Irineu Loturco 《Journal of sports sciences》2020,38(11-12):1296-1303

ABSTRACT

The aims of the present study were to provide an in-depth comparison of inter-limb asymmetry and determine how consistently asymmetry favours the same limb during different vertical jump tests. Eighteen elite female under-17 soccer players conducted unilateral squat jumps (SJ), countermovement jumps (CMJ) and drop jumps (DJ) on a portable force platform, with jump height, peak force, concentric impulse and peak power as common metrics across tests. For the magnitude of asymmetry, concentric impulse was significantly greater during the SJ test compared to CMJ (p = 0.019) and DJ (p = 0.003). No other significant differences in magnitude were present. For the direction of asymmetry, Kappa coefficients revealed fair to substantial levels of agreement between the SJ and CMJ (Kappa = 0.35 to 0.61) tests, but only slight to fair levels of agreement between the SJ and DJ (Kappa = ?0.26 to 0.18) and CMJ and DJ (Kappa = ?0.13 to 0.26) tests. These results highlight that the mean asymmetry value may be a poor indicator of true variability of between-limb differences in healthy athletes. The direction of asymmetry may provide a useful monitoring tool for practitioners in healthy athletes, when no obvious between-limb deficit exists.  相似文献   

Outstanding performances during elite-standard short and middle-distance finals and the hyperandrogenism regulation—A detailed analysis of Caster Semenya’s results     

Jonathan Ospina-Betancurt  Maria S. Zakynthinaki 《Journal of sports sciences》2020,38(6):703-709

ABSTRACT

Recently, there has been much controversy over the International Association of Athletics Federation (IAAF) regulations regarding eligibility to compete and natural testosterone levels in female athletes. Much interest lies in the analysis of Caster Semenya's extraordinary performance. The objective of this work were, a) Complete an analysis of Caster Semenya's results during the 800m finals and b) search for existing similar performances by other female athletes. We analysed the results of the finals of all IAAF World Championships and Olympic Games from 1984–2016, including the 800m results of the Diamond Leagues 2016–2018. Exponential curves were fit to the data to characterise and predict performance for each event. Caster Semenya's finishing times before her ineligibility to compete and after the suspension of the IAAF hyperandrogenism regulation were found to be 1.24% and 1.49%, respectively, faster than the characteristic performance of the elite-standard in the women’s 800m final. Other female athletes, with finishing times faster than the ones predicted by the characteristic curves were also discovered. The percentage difference in performance between Caster Semenya and the other participants did not reach 3% in the 800m event. No conclusions can be drawn regarding extraordinary results ever performed during the 100m, 200m or 400m finals.  相似文献   

Changes in kinematics and arm–leg coordination during a 100-m breaststroke swim     

Samuel W. Oxford  Rob S. James  Michael J. Price  Carl J. Payton  Michael J. Duncan 《Journal of sports sciences》2017,35(16):1658-1665

The purpose of this study was to compare arm–leg coordination and kinematics during 100 m breaststroke in 26 (8 female; 18 male) specialist breaststroke swimmers. Laps were recorded using three 50-Hz underwater cameras. Heart rate and blood lactate were measured pre- and post-swim. Arm–leg coordination was defined using coordination phases describing continuity between recovery and propulsive phases of upper and lower limbs: coordination phase 1 (time between end of leg kick and start of the arm pull phases); and coordination phase 2 (time between end of arm pull and start of leg kick phases). Duration of stroke phases, coordination phases, swim velocity, stroke length (SL), stroke rate (SR) and stroke index (SI) were analysed during the last three strokes of each lap that were unaffected by turning or finishing. Significant changes in velocity, SI and SL (P < 0.05) were found between laps. Both sexes showed significant increase (P < 0.05) in heart rate and blood lactate pre- to post-swim. Males had significantly (P < 0.01) faster swim velocities resulting from longer SLs (P = 0.016) with no difference in SR (P = 0.064). Sex differences in kinematic parameters can be explained by anthropometric differences providing males with increased propelling efficiency.  相似文献   

模糊手法与等值翻译     

张亚利 《福建工程学院学报》2004,2(3):343-346

东西方文化的不同以及英汉语言表达的差距势必造成英汉翻译上的困难。但语言传译贵在等值传神而不应该受制于原文语言表达方式。文章拟探讨英汉翻译实践中运用正反、虚实、顺逆、直曲、增减、揉合等模糊翻译手法以实现跨文化语言内容的等值传递的可能性。  相似文献   

The moderating role of cultural orientation in explaining temporal orientation of self-referencing     

Seungae Lee  Jun Heo 《亚洲交流杂志》2016,26(4):333-349

A psychological process called self-referencing justifies the use of ‘you’ statements in advertisements; the more an individual relates an ad to him/herself, the greater the likelihood of recall and favorable evaluation. Self-referencing can be differentiated based on the temporal dimension of the self being activated while processing advertisements: when people remember themselves in the past they engage in retrospective self-referencing whereas they engage in anticipatory self-referencing when imagining themselves in the future. The current study examined the moderating role of consumers’ cultural background (i.e. long-term vs. short-term orientation) on the effects of temporal orientation of self-referencing. A corollary of this premise is that the match between cultural time orientation and the type of self-referencing activated by an ad will increase the extent of viewers’ self-referencing as well as advertising effectiveness. Further, this study confirmed a mediating role of self-referencing in explaining the match effects. The findings inform the extant literature on self-referencing and also provide managerial implications for international advertising practitioners.  相似文献   

浅析英语教学中的文化渗透     

龚冰 《湖州职业技术学院学报》2007,5(1):71-73

语言是文化的一部分,不能独立于文化而存在。由于不同的民族有着不同的社会文化背景,因此,学习一种语言必须了解这种语言所承载的文化。英语教学中必须注重对学生进行文化渗透,首先,应充分利用现有教材,立足课堂,进行文化渗透,其次,要不断开拓第2课堂,加强文化渗透。  相似文献   

移动图书馆服务质量的感知差异性分析     

郑德俊  王硕 《图书情报工作》2016,60(21):6-16

[目的/意义] 移动图书馆的快速发展引发了学者们对移动图书馆服务质量的广泛关注,从用户感知差异的角度去探讨服务质量有助于提升移动图书馆服务水平。[方法/过程] 使用自建的移动图书馆服务质量观测量表,采用方差分析、象限分析和聚类分析方法,从用户的性别、学科类型、使用经验和机构属性进行差异性分析。[结果/结论] 研究发现用户对服务质量的感知存在差异性,移动图书馆服务应重视以服务推广为核心的服务宣传,并以交互体验改进作为未来服务质量的改进重点。  相似文献   

从认知语言学角度看英汉语时间概念隐喻的差异     

龚萍 《荆州师范学院学报》2005,28(4):104-106

英汉语在“时间是空间”、“时间流逝是运动”、“时间是金钱”、“时间是实体”等主要时间概念隐喻及相应的语言表达形式中虽有很多相同之处，但也存在着差异。这些差异来源于英汉不同的认知和社会文化背景。  相似文献   

Physical activity profiles and selected muscular fitness variables in English schoolchildren: A north–south divide?     

Lee Ingle  Ashlie Stephenson  Gavin R. Sandercock 《European Journal of Sport Science》2016,16(8):1187-1196

The aim of the study was to compare and contrast habitual physical activity (PA) profiles and muscular fitness in schoolchildren from northern and southern regions of England. Data were collected from two secondary schools in the north east (NE) of England. The study procedures followed methods employed by the East of England Healthy Hearts Study in 10–16-year-old boys and girls based in the south east (SE) region of England and data were compared. Habitual physical activity (PAQ-A), vertical jump test, and hand-grip (HG) strength were assessed. We converted raw scores from all assessments to age- and sex-normalised z-scores. We recruited 597 children (58% boys) in the NE and compared findings to 597 age- and sex-matched boys and girls from the SE. Boys in the SE had significantly stronger HG scores, jumped higher, were more powerful (mean peak power: 2131?W vs. 1782?W; P?P?P?相似文献   

语言教学中的文化教学     

李润娥 《忻州师范学院学报》2007,23(3):114-115

语言和文化互相影响，互相作用，学生如只学语言而不学其文化，将无法真正掌握一门语言也无法正确运用。文化差异决定语言差异，导致语用差异及价值观念的差异。因此，在语言教学中应渗透文化教学。  相似文献