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1.
Abstract Kenyan athletes have dominated international distance running in recent years. Explanations for their success include favourable physiological characteristics, which could include favourable genetic endowment, and advantageous environmental conditions. The aim of this study was to compare the demographic characteristics of elite Kenyan runners with those of the general Kenyan population. Questionnaires, administered to 404 elite Kenyan runners specializing in distances ranging from the 800 m to the marathon and 87 Kenyan controls, obtained information on place of birth, language, and distance and method of travel to school. Athletes were separated into two groups according to athletic success: those who competed in international competition and those who competed in national competition. The athletes differed from controls in regional distribution, language, and distance and method of travel to school; athletes also differed from each other with the exception of method of travel to school. Most national and international athletes came from the Rift Valley province (controls 20%, national athletes 65%, international athletes 81%), belonged to the Kalenjin ethnic group (controls 8%, national athletes 49%, international athletes 76%) and Nandi sub-tribe (controls 5%, national athletes 25%, international athletes 44%), and spoke languages of Nilotic origin (controls 21%, national athletes 60%, international athletes 79%). A higher proportion of all athletes ran to school each day (controls 22%, national athletes 73%, international athletes 81%) and covered greater distances. In conclusion, Kenyan runners are from a distinctive environmental background in terms of geographical distribution, ethnicity and travelled further to school, mostly by running. These findings highlight the importance of environmental and social factors in the success of Kenyan runners. 相似文献
2.
Mooses and colleagues suggest that running economy alone does not explain superior distance running performance in elite Kenyan runners. Whilst we agree with the multi-factorial hypothesis for Kenyan running success, we do not believe that running economy can be overlooked to the extent that it was based on this particular study. Based on the methods used and the range of athletes tested, in this response letter we question whether this study provides any basis for downplaying the influence of running economy or suggesting that other factors compensate for it to enable superior performance. 相似文献
3.
Nicholas Tam Jordan Santos-Concejero Ross Tucker Robert P. Lamberts Lisa K. Micklesfield 《Journal of sports sciences》2018,36(4):456-461
Impact loading in athletes participating in various sports has been positively associated with increased bone mineral density (BMD), but this has not been investigated in elite Kenyan runners. Body composition and site-specific BMD measures quantified with dual x-ray absorptiometry were measured in 15 elite male Kenyan runners and 23 apparently healthy South African males of different ethnicities. Training load and biomechanical variables associated with impact loading, such as joint stiffness, were determined in the elite Kenyan runners. Greater proximal femur (PF) BMD (g · cm?2) was higher (P = 0.001, ES = 1.24) in the elite Kenyan runners compared with the controls. Six of the 15 (40%) Kenyan runners exhibited lumbar spine (LS) Z-Scores below ?2.0 SD, whereas this was not found in the apparently healthy controls. PFBMD was associated with training load (r = 0.560, P = 0.003) and ankle (r = 0.710, P = 0.004) and knee (r = 0.546, P = 0.043) joint stiffness. Elite Kenyan runners exhibit greater PFBMD than healthy controls, which is associated with higher training load and higher joint stiffness. Our results reaffirm the benefits of impact loading on BMD at a weight-bearing site, while a high prevalence of low LSBMD in the elite Kenyan runners is hypothesised to be the result of a mismatch between energy intake and high training load. Future research investigating energy availability in Kenyan runners and the possible association with musculoskeletal injury should be investigated. 相似文献
4.
Naoki Kikuchi Eri Miyamoto-Mikami Haruka Murakami Tomohiro Nakamura Seok-Ki Min Masuhiko Mizuno 《European Journal of Sport Science》2016,16(6):694-701
Aim: Recent meta-analyses of the literature confirmed the association between the RR+RX genotype of the ACTN3 R577X polymorphism and elite sprint/power athletic status in Europeans but not in Asians and Africans, while the association between the R577X genotype and elite endurance athlete status is less convincing. The aim of the present study was to investigate the association between the ACTN3 R577X genotype and elite athlete status in a large Asian (Japanese) cohort of track and field athletes. Methods: One-thousand fifty-seven Japanese track and field athletes (627 sprint/power athletes and 430 endurance athletes) and 810 Japanese controls were genotyped for the ACTN3 R577X polymorphism (rs1815739) by using the TaqMan® SNP Genotyping Assay. Results: Elite sprint/power athletes had a higher frequency of the RR+RX genotype than the controls (OR: 1.59, 95% CI: 1.16–2.18; P?=?.003). A significant linear correlation was found between the RR?+?RX genotype and athlete status (i.e. regional?P?=?.001 for trend) and long-distance runners (regional: 65%, national: 72%, international: 82%; P?=?.030 for trend). Conclusions: The data obtained for this large Asian (Japanese) cohort of track and field athletes served to confirm the association between the RR?+?RX genotype of the ACTN3 R577X polymorphism and elite sprint/power athlete status and also the association between the ACTN3 RR?+?RX genotype and long-distance running athletic status. 相似文献
5.
HiHiLo与LoHi两种低氧训练效果的比较研究 总被引：6，自引：1，他引：5
研究目的：比较“高住-高练-低训”（HiHiLo）和“低住-高练”（LoHi）两种低氧训练的效果，为确定低氧训练方案提供理论与实验依据。研究对象和方法：研究对象为13名国家队女子中长跑运动员和12名少体校男子中长跑运动员。HiHiLo组每晚居住于14．7％O2低氧环境10h，白天除照常训练外，每周进行3次低氧运动。LoHi组居住于常氧环境，其他与HiHiLo组相同。测定低氧训练前及实验期间每周血象指标（RBC、Hct、Hb）和低氧训练前后最大耗氧量（VO2max）、无氧闽强度（AT）。实验结果：4周低氧训练，优秀长跑运动员和业余长跑运动员在HiHiLo期间的RBC、HCt、Hb明显增高（P〈0．05），在第3、4周出现高峰值，LoHi组变化不明显，或在大强度训练中下降。优秀长跑运动员低氧训练后HiHiLo组VO2max、AT分别提高了9％和13％，而LoHi组只增加了6％和10％。因此，HiHiLo低氧训练效果优于LoHi。 相似文献
6.
The purpose of this study was to determine how female marathon runners of varying standards differed in body composition and physique and in their training regimes, and secondly to develop predictors of distance running performance from the anthropometric and training variables. Female marathon runners (n = 36), all participants in a national 10 mile (16 km) road racing championship, were divided into three groups according to their best time for the 26.2 mile race. They were assessed for body composition and somatotype using anthropometric techniques and completed a questionnaire about their current training for the marathon. No difference was found between the groups of distance runners when measured for height, bone widths and circumferences. The three groups were found to have similar body weights of approximately 53 kg, a value which is much lower than the average for sedentary women, but which compares favourably with those from previous studies of female long distance runners. While all the runners had a lower per cent fat, as measured from skinfold thicknesses, than sedentary women, the elite runners were seen to have significantly lower values (P less than 0.05) than the other two groups. The difference in body fat was particularly reflected in the triceps skinfold value. There was also a tendency for the elite runners to be more ectomorphic and less endomorphic than the others. The better runners were seen, on the whole, to have been running longer, and to have more strenuous regimes, both in terms of intensity of training and distance run per week. Multiple regression and discriminant function analyses indicated that the number of training sessions per week and the number of years training were the best predictors of competitive performance at both 10 mile and marathon distances. They also indicated that a female long distance runner with a slim physique high in ectomorphy has the greatest potential for success. 相似文献
7.
Relationship of running economy, ventilatory threshold, and maximal oxygen consumption to running performance in high school females 总被引：1，自引：0，他引：1
L N Cunningham 《Research quarterly for exercise and sport》1990,61(4):369-374
The purpose of the study was to relate three determinants of distance running success, (a) maximal oxygen consumption (VO2max), (b) ventilatory threshold (VT), and (c) running economy (RE), to actual running time in a 5-km race (ART). Twenty-four female runners (M age = 15.9 years) from four high school teams that competed at the Massachusetts All-State 5-km Cross Country Championship Meet and placed 1st, 7th, 19th, and 20th were tested in the laboratory. The mean VO2max of these runners was 61.7 ml.kg-1.min-1, HRmax 201 b.min-1, VEmax 100 L.min-1, and RER 1.10. The VT occurred at 79% of the VO2max, and HR of 184 b.min-1 (92% of HRmax). The velocity at VT (vVT) and velocity at VO2max (vVO2max) was correlated with ART, r(22) = .78 and .77 (p less than .001), respectively. The VO2 at VT and at maximal exercise was correlated with ART by r(22) = -.66 and -.69 (p less than .001), respectively. The VO2 at 215 m.min-1 (8 mph) was poorly related to ART, r(22) = -.05, p greater than .05. It was concluded that either of the derived variables vVT and vVO2max appear to explain significant variation in distance running performance among adolescent female cross country runners. 相似文献
8.
Steffi L. Colyer Keith A. Stokes James L. J. Bilzon Danny Holdcroft 《Journal of sports sciences》2018,36(17):1930-1936
Athletes initiating skeleton runs differ in the number of steps taken before loading the sled. We aimed to understand how experimentally modifying loading distance influenced sled velocity and overall start performance. Ten athletes (five elite, five talent; 67% of all national athletes) underwent two to four sessions, consisting of two dry-land push-starts in each of three conditions (preferred, long and short loading distances). A magnet encoder on the sled wheel provided velocity profiles and the overall performance measure (sled acceleration index). Longer pre-load distances (12% average increase from preferred to long distances) were related to higher pre-load velocity (r = 0.94), but lower load effectiveness (r = ?0.75; average reduction 29%). Performance evaluations across conditions revealed that elite athletes’ preferred distance push-starts were typically superior to the other conditions. Short loading distances were generally detrimental, whereas pushing the sled further improved some talent-squad athletes’ performance. Thus, an important trade-off between generating high pre-load velocity and loading effectively was revealed, which coaches should consider when encouraging athletes to load later. This novel intervention study conducted within a real-world training setting has demonstrated the scope to enhance push-start performance by altering loading distance, particularly in developing athletes with less extensive training experience. 相似文献
9.
Elite sports are widely considered by national governments as a merit good through which many benefits to society as whole can be fostered through the stimulation of ‘national pride’ and ‘happiness’ (or ‘wellbeing’). The aim of this paper is to analyze what factors influence perceived national pride and happiness when athletes succeed at major national and/or international competitions. Based on a nation-wide survey, data was collected from n = 2006 randomly selected Germans by means of a computer assisted telephone interview. The results reveal that 66.2% respondents felt proud and 65.6% respondents were happy when German athletes were successful at major events. National pride and happiness were significantly explained through interest in elite sports, sport participation and socio-economic variables. The results reveal that there are differences between the perception of pride and that of happiness. Women, individuals with a low educational background, and low income and individuals having a migration background are the population segments who gain most from the sporting success of elite athletes. The results show in particular that the funding of elite sports and elite athletes can be considered as policy tool for social integration. 相似文献
10.
Richard G. Israel 《Research quarterly for exercise and sport》2013,84(3):521-523
Abstract The purpose of this investigation was to evaluate and quantify physiological differences among groups of distance runners. The subjects included 20 elite distance runners (8 marathon, 12 middle-long distance) and 8 good runners. Working capacity and cardiorespiratory function were determined by submaximal and maximal treadmill tests, and body composition by hydrostatic weighing. The variables studied were maximum oxygen uptake ([Vdot]O2 max), [Vdot]O2 submax, lactic acid submax, lean body weight, and fat weight. MANOVA showed that the good runners differed from the elite runners (p < 0.01) and the elite marathon runners differed from the elite middle-long distance runners (p < 0.05). Discriminant analysis showed that both functions were significant. The first was a general physiological efficiency factor that separated the good and elite runners. The second separated the elite marathon and middle-long distance groups. The second function showed that the marathon runners had lower lactic acid submax values. The middle-long distance runners had higher [Vdot]O2 max values. Classification analysis was used to evaluate the accuracy of the discriminant analysis; 80% of the elite runners were correctly classified as marathon or middle-long distance runners. The discriminant functions were used to develop a multivariate scaling model for evaluating distance runners. Two premier runners, one marathoner (F. Shorter) and one middle-long distance runner (S. Prefontaine), were found to be at the extremes of the scale. The data showed that the discriminant functions provided a valid model for evaluating differences among elite distance runners. 相似文献
11.
《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
12.
13.
优秀游泳运动员最佳竞技年龄特征分析 总被引：2，自引：0，他引：2
本文采用文献资料和数理统计法，对现阶段国内外优秀游泳运动员最佳竞技年龄特点进行分析，认为我国优秀游泳运动员的最佳竞技年龄区比世界优秀游泳运动员保持短。我国优秀游泳动员最佳竞技年龄明显早于世界优秀游泳运动员，世界优秀男女游泳运动员的平均最佳竞技年龄均为22岁；我国优秀男女游泳运动员的最佳竞技年龄分别为20岁和17．5岁。建议早期训练避免专项化过早；加强对运动员综合能力的培养；正视并且重视比赛和训练中运动成绩的短暂停滞。 相似文献
14.
Cieszczyk P Ostanek M Leońska-Duniec A Sawczuk M Maciejewska A Eider J Ficek K Sygit K Kotarska K 《Journal of sports sciences》2012,30(1):31-35
The aims of this study were to determine the distribution of the AMPD1 genotype among groups of high-level Polish power-oriented athletes, and to investigate potential associations between genetic polymorphism in exon 2 of the AMPD1 gene and power-oriented athlete status. Altogether, 158 male Polish power-oriented athletes were genotyped by PCR-RFLP. The genetic control group comprised 160 unrelated male volunteers. We observed significant differences in genotype distribution when all 158 athletes (89.25% CC, 10.75% CT, 0.00% TT; P = 0.0025) were compared with controls (75.00% CC, 23.75% CT, 1.25% TT). A significant deficiency of the T allele was noted in all subgroups (short-distance runners: 5.21%, P = 0.032; short-distance swimmers: 5.56%, P = 0.031; weightlifters: 5.36%, P = 0.024) compared with controls (13.13%), while this trend was even stronger when the frequency of the T allele was compared between controls and all 158 athletes (5.38%, P = 0.0007). Our results indicate a lower frequency of the AMPD1 exon 2 T34 allele in elite Polish power-oriented athletes. Our data suggest that the C allele may help athletes to attain elite status in power-oriented sports. 相似文献
15.
对国内外曾排名在前3位生育后又重返田径场比赛的女子田径运动员53人的资料进行了研究分析,发现其中69.8％的运动员生育后及时恢复训练,成绩再次提高,出现又一个高峰期。研究认为,生育后的优秀田径运动员应在6个月内进行科学的恢复训练,这对运动成绩的保持和提高有很大的影响。 相似文献
16.
In this study, we examined aspects of the 4 2 100 m relay that are amenable to mathematical analysis. We looked at factors that affect the time required to complete the relay, focusing on the performance of elite male athletes. Factors over which the individual athletes, and the team coach, can exercise some control are: the starting positions of the runners on legs 2, 3 and 4, the positions at which baton exchanges occur, the free distances at the baton exchanges and the running order of the athletes. The lane draw is shown to have an important influence on the relay time, although it is outside the control of the team coach. Teams drawn in the outside lanes benefit from the inverse relation between bend radius of curvature and running speed. For teams composed of athletes with different times over 100 m, we show that the fastest relay times are achieved with the fastest athlete taking the first leg, with the slowest two runners allocated to the final two legs. 相似文献
17.
In this study, we examined aspects of the 4 x 100 m relay that are amenable to mathematical analysis. We looked at factors that affect the time required to complete the relay, focusing on the performance of elite male athletes. Factors over which the individual athletes, and the team coach, can exercise some control are: the starting positions of the runners on legs 2, 3 and 4, the positions at which baton exchanges occur, the free distances at the baton exchanges and the running order of the athletes. The lane draw is shown to have an important influence on the relay time, although it is outside the control of the team coach. Teams drawn in the outside lanes benefit from the inverse relation between bend radius of curvature and running speed. For teams composed of athletes with different times over 100 m, we show that the fastest relay times are achieved with the fastest athlete taking the first leg, with the slowest two runners allocated to the final two legs. 相似文献
18.
The aim of this study was to determine the effects of 7 weeks of high- and low-velocity resistance training on strength and sprint running performance in nine male elite junior sprint runners (age 19.0 - 1.4 years, best 100 m times 10.89 - 0.21 s; mean - s ). The athletes continued their sprint training throughout the study, but their resistance training programme was replaced by one in which the movement velocities of hip extension and flexion, knee extension and flexion and squat exercises varied according to the loads lifted (i.e. 30-50% and 70-90% of 1-RM in the high- and low-velocity training groups, respectively). There were no between-group differences in hip flexion or extension torque produced at 1.05, 4.74 or 8.42 rad·s -1 , 20 m acceleration or 20 m 'flying' running times, or 1-RM squat lift strength either before or after training. This was despite significant improvements in 20 m acceleration time ( P ? 0.01), squat strength ( P ? 0.05), isokinetic hip flexion torque at 4.74 rad·s -1 and hip extension torque at 1.05 and 4.74 rad·s -1 for the athletes as a whole over the training period. Although velocity-specific strength adaptations have been shown to occur rapidly in untrained and non-concurrently training individuals, the present results suggest a lack of velocity-specific performance changes in elite concurrently training sprint runners performing a combination of traditional and semi-specific resistance training exercises. 相似文献
19.
The purpose of this paper is to examine and map the process of Australian elite athlete development from an organisational perspective, that of 35 national sporting organisations (NSOs). Research on elite development has focused on the significance of economic and cultural factors (macro-level studies) and the role of sport science and athletes’ close environment (micro-level studies) in fostering success. In an effort to depict elite athlete development processes in a more inclusive way, this paper offers an evaluation of the ways elite athletes are nurtured from an Australian NSOs perspective adopting a meso-level approach (e.g., programs). The study is based on a document analysis examining 74 annual reports from 35 NSOs over a period of four years, before and after the Sydney Olympic Games and offers a generic framework of the Australian elite athlete development process. The resulting framework shows that various interested groups are involved with nurturing elite athletes through either initiating or implementing specially designed programs or other strategies that cultivate success, and helps broaden the definition of elite development. The implications of successful elite athlete development include increased finances and public profile for sports as well as the creation of pathways to increase interest in sport. 相似文献
20.
Field tests of speed and endurance may be used to evaluate the probability of success and to create efficient training strategies for sports. Currently, both invasive and non-invasive methods are used for this purpose. While invasive methods cause some discomfort to subjects, non-invasive methods may employ practices associated with the sport itself. One such method employs the linear relationship between exercise intensity or running speed and distance covered running at that speed represented on a semi-logarithmic scale. The separation of endurance runners into three different groups can be confirmed by different values for the slope coefficient (b) of this linear relation. According to findings among top Czechoslovak endurance runners, supplemented by the data of other authors, the values of coefficient b in middle-distance runners are in the range -2.166 to -1.700, in long-distance runners -1.520 to -1.050 and in marathon runners -0.836 to -0.436. Similarly, a separation of young endurance runners into groups of middle-distance and long-distance runners must be within the range -2.158 to -1.800 and for young long-distance runners -1.700 to -1.300. Based on these findings, the optimum competitive distance for adult athletes can be established in relation to current training status. In young athletes, it is possible to select gifted runners with predispositions for middle-distance and long-distance running. For both groups of athletes, more efficient training methods can be selected to optimize their predispositions for maximal performance. 相似文献