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1.
In this study, we analysed running world records and found that the mean speed of the race, mu, as a function of the record time, tau, can be described asymptotically by two well-defined scaling laws of the form mu approximately tau(-beta). There is a break in the scaling laws (approximately 1000 m) between the shorter and the longer races at a characteristic time of around 150-170 s, after which a new scaling regime emerges. This is the first occasion that this characteristic time has been clearly found in physical terms; we interpreted it as the transition time between the anaerobic and the aerobic energy expenditure of athletes. This phenomenon is independent of the athletes' sex and is also found in swimming races with similar values of the characteristic time. We also investigated the forecasting of world records using historical data. Using an approach based on the identification of non-Poissonian events for a sequence of temporal point processes, we found that the sequence of improvements in all athletic records from 1900 to the present day cannot be considered as a sequence of completely random events. 相似文献
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An analysis of selected kinematic variables in national and elite male and female 100-m and 200-m breaststroke swimmers 总被引：2，自引：1，他引：1
The kinematic analysis of competition breaststroke swimming has tended to focus on the mean values of swimming speed, stroke rate and stroke length; values in individual lengths, as well as the start, turns and finish, have largely been ignored. This study includes all such variables and aims to improve the coach's holistic understanding of breaststroke racing by determining the relationships and differences between and within these selected kinematic variables. We also compare 100-m events with 200-m events to determine if there are characteristic differences between them. Competitive breaststroke swimming performances in 100-m events (males: n = 159, finishing time = 65.05 +/- 2.62 s; females: n = 158, finishing time = 74.04 +/- 3.66 s) and 200-m events (males: n = 159, finishing time = 141.47 +/- 6.15 s; females: n = 158, finishing time = 158.66 +/- 7.87 s) were collected and analysed from 12 world, international and national championships. The better 100-m and 200-m breaststroke swimmers were found to demonstrate greater competency in the kinematic variables measured, except stroke kinematics, which were unique to each individual. These findings suggest that coaches should place emphasis on all of the kinematic components in training and that they should attempt to identify the stroke rate to stroke length ratio most appropriate for the individual. Finally, characteristic differences do exist between the 100-m and 200-m events, which has implications for how swimmers might train for each event. 相似文献
3.
The kinematic analysis of competition breaststroke swimming has tended to focus on the mean values of swimming speed, stroke rate and stroke length; values in individual lengths, as well as the start, turns and finish, have largely been ignored. This study includes all such variables and aims to improve the coach's holistic understanding of breaststroke racing by determining the relationships and diff erences between and within these selected kinematic variables. We also compare 100-m events with 200-m events to determine if there are characteristic diff erences between them. Competitive breaststroke swimming performances in 100-m events (males: n = 159, finishing time = 65.05 - 2.62 s; females: n = 158, finishing time = 74.04 - 3.66 s) and 200-m events (males: n = 159, finishing time = 141.47 - 6.15 s; females: n = 158, finishing time = 158.66 - 7.87 s) were collected and analysed from 12 world, international and national championships. The better 100-m and 200-m breaststroke swimmers were found to demonstrate greater competency in the kinematic variables measured, except stroke kinematics, which were unique to each individual. These findings suggest that coaches should place emphasis on all of the kinematic components in training and that they should attempt to identify the stroke rate to stroke length ratio most appropriate for the individual. Finally, characteristic diff erences do exist between the 100-m and 200-m events, which has implications for how swimmers might train for each event. 相似文献
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对历届奥运会男女径赛不同项目的比赛成绩t与比赛距离S及比赛届次N进行统计分析,以回归分析法建立了t-N二者关系模型及t-N-S三者关系模型,可用于分析与预测各届次的比赛成绩,提出了基于近期奥运会最高纪录的各项径赛最好成绩t与径赛距离S的关系,可较准确预测近期未来奥运各项径赛是否可破纪录的情况。根据这一预测,第29届奥运会男女径赛将在100m、800m、1500m、5000m项目上有望提高或打破奥运会纪录。 相似文献
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Martin Weiss Alexandra Newman Ceri Whitmore Stephan Weiss 《European Journal of Sport Science》2016,16(4):393-401
Sprint and distance running have experienced remarkable performance improvements over the past century. Attempts to forecast running performances share an almost similarly long history but have relied so far on relatively short data series. Here, we compile a comprehensive set of season-best performances for eight Olympically contested running events. With this data set, we conduct (1) an exponential time series analysis and (2) a power-law experience curve analysis to quantify the rate of past performance improvements and to forecast future performances until the year 2100. We find that the sprint and distance running performances of women and men improve exponentially with time and converge at yearly rates of 4% ± 3% and 2% ± 2%, respectively, towards their asymptotic limits. Running performances can also be modelled with the experience curve approach, yielding learning rates of 3% ± 1% and 6% ± 2% for the women's and men's events, respectively. Long-term trends suggest that: (1) women will continue to run 10–20% slower than men, (2) 9.50 s over 100 m dash may only be broken at the end of this century and (3) several middle- and long-distance records may be broken within the next two to three decades. The prospects of witnessing a sub-2 hour marathon before 2100 remain inconclusive. Our results should be interpreted cautiously as forecasting human behaviour is intrinsically uncertain. The future season-best sprint and distance running performances will continue to scatter around the trends identified here and may yield unexpected improvements of standing world records. 相似文献
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《运动与健康科学(英文)》2021,10(5):537-549
The pacing behaviors used by elite athletes differ among individual sports, necessitating the study of sport-specific pacing profiles. Additionally, pacing behaviors adopted by elite runners differ depending on race distance. An “all-out” strategy, characterized by initial rapid acceleration and reduction in speed in the later stages, is observed during 100 m and 200 m events; 400 m runners also display positive pacing patterns, which is characterized by a reduction in speed throughout the race. Similarly, 800 m runners typically adopt a positive pacing strategy during paced “meet” races. However, during championship races, depending on the tactical approaches used by dominant athletes, pacing can be either positive or negative (characterized by an increase in speed throughout). A U-shaped pacing strategy (characterized by a faster start and end than during the middle part of the race) is evident during world record performances at meet races in 1500 m, 5000 m, and 10,000 m events. Although a parabolic J-shaped pacing profile (in which the start is faster than the middle part of the race but is slower than the endspurt) can be observed during championship 1500 m races, a negative pacing strategy with microvariations of pace is adopted by 5000 m and 10,000 m runners in championship races. Major cross country and marathon championship races are characterized by a positive pacing strategy; whereas a U-shaped pacing strategy, which is the result of a fast endspurt, is adopted by 3000 m steeplechasers and half marathoners. In contrast, recent world record marathon performances have been characterized by even pacing, which emphasizes the differences between championship and meet races at distances longer than 800 m. Studies reviewed suggest further recommendations for athletes. Throughout the whole race, 800 m runners should avoid running wide on the bends. In turn, during major championship events, 1500 m, 5000 m, and 10,000 m runners should try to run close to the inside of the track as much as possible during the decisive stages of the race when the speed is high. Staying within the leading positions during the last lap is recommended to optimize finishing position during 1500 m and 5000 m major championship races. Athletes with more modest aims than winning a medal at major championships are advised to adopt a realistic pace during the initial stages of long-distance races and stay within a pack of runners. Coaches of elite athletes should take into account the observed difference in pacing profiles adopted in meet races vs. those used in championship races: fast times achieved during races with the help of one or more pacemakers are not necessarily replicated in winner-takes-all championship races, where pace varies substantially. Although existing studies examining pacing characteristics in elite runners through an observational approach provide highly ecologically valid performance data, they provide little information regarding the underpinning mechanisms that explain the behaviors shown. Therefore, further research is needed in order to make a meaningful impact on the discipline. Researchers should design and conduct interventions that enable athletes to carefully choose strategies that are not influenced by poor decisions made by other competitors, allowing these athletes to develop more optimal and successful behaviors. 相似文献
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论当今世界优秀田径运动员身高、体重和克托莱指数的项群特征 总被引：35，自引：4，他引：31
采用文献法、数理统计法（单因素方差分析、相关分析）、归纳法,以1996亚特兰大奥运会田径决赛前8名运动员为研究对象,探讨当今世界优秀田径运动员身高、体重和克托莱指数的项群特征,以揭示田径运动不同亚类项群及其分组项目运动员在上述3指标上的量值模式及特点。结果表明;当今世界优秀田径运动员的身高、体重和克托莱指数具有鲜明的项群特征。不同亚类项群及其分组项目运动员在上述3指标上不仅差异显著,而且其量值排序具有一致性。说明上述3指标可作为基础形态指标应用于不同田径亚类项群及其分组项目的科学选材。建议尽快建立中国田径不同亚类项群及其分组项目优秀运动员身高、体重和克托莱指数的常模标准,以提高我国田径运动项目选材的科学性。 相似文献
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《Measurement in physical education and exercise science》2013,17(4):205-223
The specific purposes of this study were (a) to identify the best mathematical model and the best data set for predicting men's future world-best track and field performance, (b) to predict ultimate performances for seven selected track and field events, and (c) to develop a new "random sampling" model to predict performance for those events that have exhibited asymptotic-like behavior over the last 15 years. Linear and nonlinear models were used to fit world record data and best performance per year data to identify the best fitting model. Extreme value theory and Monte Carlo simulation methods were used to derive predicted future performances under the random sampling model for the 1,500-m event. The results showed that (a) an exponential model relating running time and historical year with yearly best performance data is the most valid deterministic model for the prediction of world records and ultimate performance, and (b) the random sampling model is an effective method to predict future world records for the 1,500-m event, the only event to exhibit asymptotic performance over the last 15 years. 相似文献
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对田径世界纪录非训练因素的研究 总被引：1，自引：0，他引：1
李强 《武汉体育学院学报》2002,36(2):71-72
从田径世界纪录设置，以及产生的国家、城市、性别、年龄等非训练因素的比较分析，探讨了田径世界纪录的发展规律。 相似文献
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近代体育运动的发展表明，田径运动是其它一切运动项目的基础，它不仅需要其它项目所要求的身体素质，还直接决定着体育的整体发展水平。随着世界竞技体育运动的不断发展，田径运动越来越被世界各国所重视，这是因为田径运动水平的高低不仅是衡量一个国家体育运动水平高低和民族体质强弱的重要标志，同时也反映了一个国家竞技体育的整体水平。故有“得田径者得天下”和“田径强国就是体育强国”的论断。本文在查阅大量相关资料和文献的基础上。运用文献资料法、数理统计法和比较分析法，对1980--2004年我国男子田径项目各单项每年的最好成绩进行统计、研究和分析，以期了解1980年以来中国男子田径运动各单项的发展态势以及与世界先进水平的差距，为有关体育部门制定相关政策、法规提供依据。 相似文献
12.
世界田径纪录不断涌现。“早期专门化训练”引起了中外教练员和体育界人士的关注 ,它直接关系到是否能培养出攀登世界体育高峰的运动员的重要问题。我们基层体校的教练员 ,应根据所从事的运动项目特点 ,对运动员的身材、素质、气质的要求 ,进行科学的选材。在训练过程中 ,按照少年儿童的特点和系统训练的要求 ,正确认识“早期专门化训练”和“身体素质全面发展”之间的辩证关系。 相似文献
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Foot strike patterns and ground contact times during high-calibre middle-distance races 总被引：1，自引：1，他引：0
Abstract The aims of this study were to examine ground contact characteristics, their relationship with race performance, and the time course of any changes in ground contact time during competitive 800?m and 1500?m races. Twenty-two seeded, single-sex middle-distance races totalling 181 runners were filmed at a competitive athletics meeting. Races were filmed at 100?Hz. Ground contact time was recorded one step for each athlete, on each lap of their race. Forefoot and midfoot strikers had significantly shorter ground contact times than heel strikers. Forefoot and midfoot strikers had significantly faster average race speed than heel strikers. There were strong large correlations between ground contact time and average race speed for the women's events and men's 1500?m (r?=?-0.521 to -0.623; P?相似文献
14.
目的：从运动员选材角度探讨短跑和中长跑项目运动员在跳深实验中支撑时间的特征，为支撑时间应用于田径运动员选材提供依据。方法：以上海市一、二线短跑和中长跑共84名运动员为研究对象。所有研究对象均进行身高、体重、跳深实验测试，分组研究两项目运动员支撑时间特征。结果：短跑男子优秀组最快和平均支撑时间都快于一般组（P＜0.05），女子优秀组最快和平均支撑时间也都快于一般组（P＞0.05），中长跑组也表现基本一致的趋势；项目之间进行比较也基本表现出一致性趋势，也就是短跑组最快和平均支撑时间基本快于相同运动等级中长跑组（P＞0.05）。结论：支撑时间在短跑和中长跑项目中具有明显的项目特征和等级特征，可以应用于短跑或中长跑项目选材。 相似文献
15.
The rules of competitive boardsailing events were changed before the Atlanta Olympic Games. Pumping the sail (pulling repeatedly on the rig) is now allowed and the duration of races has been shortened. Eight members of the French national team (mean age 23+/-2.7 years) participated in this study. Their cardiac and metabolic responses were assessed by measuring heart rate and blood lactate concentration during various competitive events in two strengths of wind (light vs. moderate). Heart rate was higher in light (87.4+/-4.3% HRmax; mean racing time 37 min) than in moderate wind conditions (82.9+/-5.3% HRmax; mean racing time 33 min). The mean post-race blood lactate concentration (5.2+/-1.0 mmol x l(-1)) was not affected by the wind conditions. Mean heart rate was highest during downwind legs (88.0+/-3.1% HRmax; duration 7-10 min). The races consisted of two laps, the first of which induced significantly higher cardiac demands than the second. We conclude that the changes to the rules of competitive boardsailing have increased the cardiac and metabolic efforts involved. 相似文献
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采用文献综述法，阐述了现代中长跑训练的新方法、新理念，运用运动生理生化知识理论，对中长跑运动员的能量供应规律及疲劳恢复进行了科学的研究，旨在为提高中长跑运动员的运动成绩提供借鉴。 相似文献
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Hans Erik Næss 《国际体育史杂志》2017,34(7-8):535-553
As the governing body of world motorsports since 1904, Fédération Internationale de l’Automobile (FIA) has, through the growth of Formula 1, become increasingly embedded in the globalization of commerce and faced with difficult political issues. Specifically, FIA events are used to sanitize the image of undemocratic countries, and FIA is, thus, becoming increasingly entangled in spheres other than sport. This presents a challenge to a sporting body which traditionally follows the principle of not mixing sport and politics. To explore this topic, two Formula 1 races where sport and politics are intertwined are chosen as examples: the 1985 South African Grand Prix and the 2016 Azerbaijan Grand Prix. As the holding of both events evoked controversy, for various reasons, this paper investigates whether something has changed at FIA along the way, and, in that case, what? As findings demonstrate, while the races differ and the context has changed, the FIA has kept its policy despite the fact that it has become increasingly difficult to maintain its neutral stance. 相似文献
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Santiago Veiga Andreu Roig Miguel A. Gómez-Ruano 《European Journal of Sport Science》2016,16(8):919-926
The main objectives of the present research were (1) to examine the relationships between the distances travelled underwater during the start and turn segments with swimming race performance at the elite level and (2) to determine if the individualised-distance start and turn parameters affect the overall race performance. The race parameters of the 100 and 200?m events during 2013 World Championships were measured by an innovative image-processing system (InThePool® 2.0). Overall, 100?m race times were largely related to faster start velocities in men's breaststroke and freestyle events. Conversely, overall, 200?m race times were largely related to longer starting distances in the women's butterfly events, to longer turn distances in men's and women's backstroke and women's butterfly events and to shorter turn distances in women's freestyle events. Changes on the start or turn velocities could represent moderate time improvements in most of the 100?m events, whereas modifications on the start or turn distances (especially in the last turn) could provide elite swimmers with time improvements of practical importance on the 200?m events. The evaluation of races by individualised-distance parameters should be provided to elite swimmers in order to decide the most appropriate race segment configuration for each event. 相似文献