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1.
This study investigated the evolution of physical and technical performances in the English Premier League (EPL), with special reference to league ranking. Match performance observations (= 14,700) were collected using a multiple-camera computerised tracking system across seven consecutive EPL seasons (2006–07 to 2012–13). Final league rankings were classified into Tiers: (A) 1st–4th ranking (= 2519), (B) 5th–8th ranking (= 2965), (C) 9th–14th ranking (= 4448) and (D) 15th–20th ranking (= 4768). Teams in Tier B demonstrated moderate increases in high-intensity running distance while in ball possession from the 2006–07 to 2012–13 season (< 0.001; effect size [ES]: 0.68), with Tiers A, C and D producing less pronounced increases across the same period (< 0.005; ES: 0.26, 0.41 and 0.33, respectively). Large increases in sprint distance were observed from the 2006–07 to 2012–13 season for Tier B (< 0.001; ES: 1.21), while only moderate increases were evident for Tiers A, C and D (< 0.001; ES: 0.75, 0.97 and 0.84, respectively). Tier B demonstrated large increases in the number of passes performed and received in 2012–13 compared to 2006–07 (< 0.001; ES: 1.32–1.53) with small-to-moderate increases in Tier A (< 0.001; ES: 0.30–0.38), Tier C (< 0.001; ES: 0.46–0.54) and Tier D (< 0.001; ES: 0.69–0.87). The demarcation line between 4th (bottom of Tier A) and 5th ranking (top of Tier B) in the 2006–07 season was 8 points, but this decreased to just a single point in the 2012–13 season. The data demonstrate that physical and technical performances have evolved more in Tier B than any other Tier in the EPL and could indicate a narrowing of the performance gap between the top two Tiers.  相似文献   
2.
ABSTRACT

The aims of this study are (a) to describe the evolution of neuromuscular performance over an 18 year period within a Spanish elite reserve team; (b) to check if there were any relation between the playing position and sprint and jump performances and (c) to look into the alleged impact of this factor on the top playing level attained by the soccer players. We considered the physical tests (5 m and 15 m sprint times and countermovement jump (CMJ) height) made by 235 players enrolled in the reserve team of the Club from 1994 to 2012 and the highest competitive-level they achieved: Spanish first (n = 39) and second divisions (n = 36) and semi-professional (n = 160). Furthermore, the players were classified according to their playing positions. The main findings were a very-likely/most-likely lower neuromuscular performance (ES = 0.48–0.68, small to moderate) in the last six-season term (2006–2012) than in the first term (1994–2000); possibly/very-likely lower performances in sprinting and CMJ (ES = 0.22–0.55, small) by central defenders (CDs) and midfielders than by other playing positions; very-likely better performances in sprinting and jumping by first and second divisions central defenders than by semi-professional central defenders (ES = 0.90–1.02, moderate). Sprint and jump performances are not a relevant physical parameter to promote to the top level of soccer in Spain except for one in six of the playing positions: CDs.  相似文献   
3.
It is widely assumed that there is an eccentric hamstring muscle fibre action during the swing phase of high-speed running. However, animal and modelling studies in humans show that the increasing distance between musculotendinous attachment points during forward swing is primarily due to passive lengthening associated with the take-up of muscle slack. Later in the swing phase, the contractile element (CE) maintains a near isometric action while the series elastic (tendinous) element first stretches as the knee extends, and then recoils causing the swing leg to forcefully retract prior to ground contact. Although modelling studies showed some active lengthening of the contractile (muscular) element during the mid-swing phase of high-speed running, we argue that the increasing distance between the attachment points should not be interpreted as an eccentric action of the CE due to the effects of muscle slack. Therefore, there may actually be no significant eccentric, but rather predominantly an isometric action of the hamstrings CE during the swing phase of high-speed running when the attachment points of the hamstrings are moving apart. Based on this, we propose that isometric rather than eccentric exercises are a more specific way of conditioning the hamstrings for high-speed running.  相似文献   
4.
Abstract

The aim of this study was to examine the effects of changes in maximal aerobic (MAS) and sprinting (MSS) speeds and the anaerobic reserve (ASR) on repeated-sprint performance. Two hundred and seventy highly-trained soccer players (14.5 ± 1.6 year) completed three times per season (over 5 years) a maximal incremental running test to approach MAS, a 40-m sprint with 10-m splits to assess MSS and a repeated-sprint test (10 × 30-m sprints), where best (RSb) and mean (RSm) sprint times, and percentage of speed decrement (%Dec) were calculated. ASR was calculated as MSS-MAS. While ?RSb were related to ?MSS and ?body mass (r2 = 0.42, 90%CL[0.34;0.49] for the overall multiple regression, n = 334), ?RSm was also correlated with ?MAS and ?sum of 7 skinfolds (r2 = 0.43 [0.35;0.50], n = 334). There was a small and positive association between ?%Dec and ?MAS (r2 = 0.02 [?0.07;0.11], n = 334). Substantial ?MSS and ?MAS had a predictive value of 70 and 55% for ?RSm, respectively. Finally, ?ASR per se was not predictive of ?RSm (Cohen’s = +0.8 to ?0.3 with increased ASR), but the greater magnitude of ?RSm improvement was observed when MSS, MAS and ASR increased together (0.8 vs. +0.4 with ASR increased vs. not, additionally to MSS and MAS). Low-cost field tests aimed at assessing maximal sprinting and aerobic speeds can be used to monitor ?RS performance.  相似文献   
5.
为研究斜坡跑超速训练方法对提高运动员短跑成绩的意义,通过3台数码摄像机同步拍摄,应用视讯运动解析系统对图像进行解析,得到运动学参数,并对数据进行统计学处理,用生物力学方法确定指标来说明哪个坡度对运动员训练效果会更好,即既能增大运动员的跑速,又使动作技术结构不变形。结果表明:3°斜坡是7名受试者进行提高速度的斜坡跑超速训练所应选择的合适坡度。  相似文献   
6.
我国男子百米跑一级运动员体能水平的评价与诊断   总被引:5,自引:0,他引:5  
百米跑运动属于典型的体能类速度性竞技项目,本文以我国男子百米一级运动员19人为研究对象,采用文献资料法、问卷调查法、专家访谈法、测试法与数理统计法等研究方法,运用分层逐步回归分析筛选出了有效反映我国男子百米跑一级运动员体能水平的10项指标.对各指标与百米跑成绩间的关系进行了灰色关联分析;对运动员的体能水平进行了评价诊断.  相似文献   
7.
通过对短跑、跨栏、跳高三个速度类项目的技术比较发现,我国男子短跑落后的重要技术原因是过分强凋后蹬技术;摆动腿折叠不紧,摆速慢;步长、步频达不到应有的水平要求。  相似文献   
8.
The lower limb kinetics of curve sprinting in amputees are not well described in the literature, particularly with respect to the effect of the side of amputation. This is an issue due to the importance of the knowledge for prosthetic design and classification of athletes. Thus, the aim of this study was to investigate the influence of side of amputation on curve sprinting performance in athletes with a unilateral leg amputation. A three-dimensional motion analysis system (Vicon), four force plates (Kistler) and a modified mathematical human model (ALASKA) were used to compare clockwise and counter clockwise curve sprinting lower limb kinematics and kinetics of a Paralympic medalist with a left-sided knee exarticular amputation. Results reveal that vertical ground reaction force application and total vertical impulse were lower when the affected limb was at the inside of the curve. The unaffected limb showed joint mechanics different to those established for non-amputee athletes and might contribute better to propulsion when being the inside limb. Curve sprinting biomechanics and the ability to attain high radial velocities are directly dependent on the side of amputation relative to the curve direction in a unilateral amputee athlete of highest performance level.  相似文献   
9.
This study aimed to identify the continuous ground reaction force (GRF) features which contribute to higher levels of block phase performance. Twenty-three sprint-trained athletes completed starts from their preferred settings during which GRFs were recorded separately under each block. Continuous features of the magnitude and direction of the resultant GRF signals which explained 90% of the variation between the sprinters were identified. Each sprinter’s coefficient score for these continuous features was then input to a linear regression model to predict block phase performance (normalised external power). Four significant (p < 0.05) predictor features associated with GRF magnitude were identified; there were none associated with GRF direction. A feature associated with greater rear block GRF magnitudes from the onset of the push was the most important predictor (β = 1.185), followed by greater front block GRF magnitudes for the final three-quarters of the push (β = 0.791). Features which included a later rear block exit (β = 0.254) and greater front leg GRF magnitudes during the mid-push phase (β = 0.224) were also significant predictors. Sprint practitioners are encouraged, where possible, to consider the continuous magnitude of the GRFs produced throughout the block phase in addition to selected discrete values.  相似文献   
10.
The purpose of this study was to quantify the reliability of kinematic and kinetic variables using a sample of pre-peak-height-velocity (PHV) male athletes sprinting on a non-motorised treadmill. Following variables were measured and their normative data presented, average and peak velocity, average and peak power, average and peak horizontal force, average and peak vertical force, average step frequency, average step length, average work. Twenty-five participants performed three 5-s all-out sprints from a standing split start on a non-motorised treadmill on three separate occasions. Per cent change in the means (-3.66 to 3.35%) and coefficients of variation (0.56–7.81%) were thought reliable for all variables. However, average step rate, average horizontal force and average vertical force did not meet the standards (≥0.70) set for acceptable intraclass correlation coefficients (ICC). Due to the homogeneous group, it was expected to receive low ICC values. Therefore, youth sprinting performance can be tested reliably on a non-motorised treadmill, especially if the per cent change in the mean and CV are deemed the important reliability measures. Normative data are given for the participant’s age as well as their maturity level for kinematic and kinetic variables.  相似文献   
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