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1.
The 1990-2010 period in professional cycling is labeled by some as the epo epidemic. Surprisingly, performance enhancement by epo and blood doping is not that clear-cut for endurance athletes, leading to the question whether doping indeed strongly influenced cyclists' performances from the 1990s onwards. We examined the records (1947-2008) of the Tour de France, Giro d'Italia, and Vuelta a Espa?a (N = 181) and assessed the time it took riders to win the race. The findings revealed normally distributed performances and linear and quartic relationships in victors' performances over time that correspond with Brewer's (2002) sociohistorical analysis of professional cycling suggesting that effects of the epo epidemic on professional cyclists'achievements may be overestimated.  相似文献   

2.
Abstract

Road cycling ranks among the most intense endurance exercises. Previous studies and mathematical models describing road cycling have not analysed performances per se. We describe the evolution of road cycling performance over the past 116 years. We studied the top ten cyclists' mean speeds in eight famous classic races and three European Grand Tours, using a previously published multi-exponential model that highlights the different progression periods of an event during the century. In addition, we measured an indicator of difficulty for the Tour de France by calculating the climbing index (i.e. the total altitude climbed over total distance). The eleven races' mean speed increased progressively from 23.13 km · h?1 in 1892 to 41.19 ± 2.03 km · h?1 in 2008. Road cycling development, like other quantifiable disciplines, fits a piecewise progression pattern that follows three periods: before, between, and after the two World Wars. However, a fourth period begins after 1993, providing a speed progression of 6.38% from the third one. The Tour de France's climbing index also provided insight into a recent paradoxical relationship with speeds: when the climbing index increased, the winner's speed also increased. Our results show a major improvement (6.38%) in road cycling performance in the last 20 years and question the role of extra-physiological parameters in this recent progression.  相似文献   

3.
《Sport in History》2013,33(3):497-514
Since the Tour de France doping scandal of 1998 there has been a concerted effort to ‘clean up’ cycling. But has this meant a change in attitude regarding the use of doping within the professional cycling community? In order to compare norms and values of today's elite cyclist with those of earlier periods, three historical phases in modern cycling are identified, and an account of professional cyclists’ preparations is given for each phase. Because of the different attitudes to doping found between riders of different categories, the article considers it necessary to reject the commonly held view that elite cyclists all take part in the same deviant subculture.  相似文献   

4.
Abstract

Aerodynamic and rolling resistances are the two major resistances that affect road cyclists on level ground. Because of reduced speeds and markedly different tyre-ground interactions, rolling resistance could be more influential in mountain biking than road cycling. The aims of this study were to quantify 1) aerodynamic resistance of mountain-bike cyclists in the seated position and 2) rolling resistances of two types of mountain-bike tyre (smooth and knobby) in three field surfaces (road, sand and grass) with two pressure inflations (200 and 400 kPa). Mountain-bike cyclists have an effective frontal area (product of projected frontal area and drag coefficient) of 0.357 ± 0.023 m2, with the mean aerodynamic resistance representing 8–35% of the total resistance to cyclists' motion depending on the magnitude of the rolling resistance. The smooth tyre had 21 ± 15% less rolling resistance than the knobby tyre. Field surface and inflation pressure also affected rolling resistance. These results indicate that aerodynamic resistance influences mountain-biking performance, even with lower speeds than road cycling. Rolling resistance is increased in mountain biking by factors such as tyre type, surface condition and inflation pressure that may also alter performance.  相似文献   

5.
This study aims to describe the intensity and load demands of different stage types within a cycling Grand Tour. Nine professional cyclists, whom are all part of the same World-Tour professional cycling team, participated in this investigation. Competition data were collected during the 2016 Giro d’Italia. Stages within the Grand Tour were classified into four categories: flat stages (FLAT), semi-mountainous stages (SMT), mountain stages (MT) and individual time trials (TT). Exercise intensity, measured with different heart rate and power output based variables, was highest in the TT compared to other stage types. During TT’s the main proportion of time was spent at the high-intensity zone, whilst the main proportion of time was spent at low intensity for the mass start stage types (FLAT, SMT, MT). Exercise load, quantified using Training Stress Score and Training Impulse, was highest in the mass start stage types with exercise load being highest in MT (329, 359?AU) followed by SMT (280, 311?AU) and FLAT (217, 298?AU). Substantial between-stage type differences were observed in maximal mean power outputs over different durations. FLAT and SMT were characterised by higher short-duration maximal power outputs (5–30?s for FLAT, 30 s–2?min for SMT) whilst TT and MT are characterised by high longer duration maximal power outputs (>10?min). The results of this study contribute to the growing body of evidence on the physical demands of stage types within a cycling Grand Tour.  相似文献   

6.
At the 1984 Los Angeles Olympic Games, the US cycling team not only won its first Olympic cycling medal since 1912 but also added eight more, marking a triumph for the team and its Polish-born coach, Eddie Borysewicz. Soon, however, news leaked that the seven members of the US cycling team, four of whom won medals, had employed controversial blood transfusions. Though not prohibited by the International Olympic Committee (IOC), the news caused a firestorm within the press and led to a significant revision of the IOC Medical Commission's anti-doping rules. Previous historical scholarship has ignored this event, focusing instead on early doping scandals such as Knud Jensen or more recent controversies such as Ben Johnson and Lance Armstrong. However, this event caused a significant shift within the IOC Medical Commission's attitude towards doping. Prior to 1984, the IOC Medical Commission had hesitated to prohibit any substance, including anabolic steroids, if it could not detect the substance through testing. The willingness of the US team to experiment with new medical procedures to improve performance galvanised the Medical Commission and set in motion new anti-doping policies that remain in place today.  相似文献   

7.
Talent identification at a young age is deemed essential for many national sporting organisations to increase the chances of success for their players on the international stage. Talent identification methods can be imprecise and national tennis associations and coaches often identify talent based on performances at youth tournaments and junior rankings. However, not much is known about the relationship between the international competition performances of young tennis players and later success. This relationship is explored in this study using comparisons based on: (a) the results of 3521 players at U14 youth tournaments; (b) the rankings of 377 junior players (U18) by the International Tennis Federation; (c) the rankings of 727 professional male players by the Association of Tennis Professionals; and (d) the rankings of 779 professional players by the Women's Tennis Association. Junior performances (U18) and performances at youth tournaments (U14) appear to have a low success rate in predicting later success. No distinct age was found at which players should start to perform in order to be successful at the professional level. It is concluded that even though good performances at young ages increase athletes’ chances to become elite players, they are not a precondition for achieving later success. Therefore, this study informs talent scouts, sport development officers, coaches and high performance managers of the role that performances at international youth competitions may play in talent identification in tennis.  相似文献   

8.
Abstract

Using a two-study approach, we examined a methodology for objectively depicting team performance and form in a professional rugby union side. Study 1 developed standardized indicators to examine a team's performance in a single match relative to their previous matches over a domestic season via a performance report and form chart. This resulted in standardized performance indicators that provided instant and coherent feedback on the team's performance relative to previous standards. Study 2 then utilized this methodology to compare a match between two professional sides, played the following season, to assess the extent to which the performance by one team affected that of the other. Comparison of the two teams' performances, for the match they played against each other, identified a drop in relative performance (against previous standards) for both teams on the same performance indicators. This appeared to be due to the match being a close, hard-fought contest particularly in the tackle and around the gain-line. The findings of the two studies suggest an accurate and viable methodology for depicting team performance that is superior to the global measures previously adopted. Presenting teams' current standardized performances (i.e. form) on a single visual scale also has utility for coaches within an applied setting. Future research should further investigate the effect of one team's performance on another through both individual and team outcomes.  相似文献   

9.
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   

10.
Purpose: Several studies have demonstrated that physiological variables predict cycling endurance performance. However, it is still unclear whether the predictors will change over different performance durations. The aim of this study was to assess the correlations between physiological variables and cycling time trials with different durations. Methods: Twenty trained male cyclists (maximal oxygen uptake [VO2max] = 60.5 ± 5.6 mL/kg/min) performed 4 separate experimental trials during a 2-week period. Cyclists initially completed an incremental exercise test until volitional exhaustion followed by 3 maximal cycling time trials on separate days. Each time trial consisted of 3 different durations: 5 min, 20 min, and 60 min performed in a randomized order. Results: The main results showed that the physiological measures strongly correlated with long cycling performances rather than short and medium time trials. The time-trial mean power output was moderately high to highly correlated with peak power output and VO2max (r = .61–.87, r = .72–.89, respectively), and was moderately to highly correlated with the lactate threshold Dmax method and second ventilatory threshold (r = .52–.75, r = .55–.82, respectively). Conclusions: Therefore, trained cyclists should develop maximal aerobic power irrespective of the duration of time trial, as well as enhancements in metabolic thresholds for long-duration time trials.  相似文献   

11.
Abstract

The relationship between domestic professional tournament structure in women's tennis and the subsequent professional ranking success of a nation's female players is examined. The 2003 women's professional tennis tournament calendar provided the distribution of events in 33 countries. Criteria used to classify nations' success in women's professional tennis were as follows: number of players with Women's Tennis Association (WTA) points, number of players with Top 200 rankings, and the combined WTA ranking of a nation's Top 5 female players. Pearson product – moment correlations were performed between the number of tournaments and the three criteria. Considerable variation was observed in the number of events organized between nations (USA, n = 56; Thailand, n = 3). All countries had internationally ranked female players, and 24 nations had players ranked in the Top 200. Results revealed relationships between a nation's number of women's professional events and both that nation's number of professionally ranked players (r = 0.60; P < 0.01) and Top 200 players (r = 0.60; P < 0.01), as well as the combined ranking of their Top 5 players (r = ?0.52; P < 0.01). While a similar association was found between the number of professional events and players ranked in the men's game, there was no significant correlation between events held and the combined standing of nations' best five ranked players. Governing bodies and national associations in tennis should consider the provision of professional, domestic competition as key to the development of female tennis players.  相似文献   

12.
With the needs of experienced teachers potentially overshadowed by a focus on recruitment, the purpose of this study was to retrospectively explore the reasons why three experienced physical education teachers resigned. They were interviewed through Louis and Smith's (1990) quality of work life (QWL) model. Data suggested shared dissatisfactions related to the lack of “genuine” opportunities to participate in educational debate and decision making, and limited professional respect shown by administrators and parents. A physical education teacher's “use-by date” was proposed. Unless these issues are further explored and addressed, quality teachers will continue to abandon the service.  相似文献   

13.
《Sport in Society》2012,15(1):88-102
This study examines whether a process of internationalization has affected the level of athletic performance amongst high-level athletes competing on the world stage. Top 100 International Association of Athletics Federations (IAAF) rankings were compared at two time points: 1984 and 2006, by event and by gender. We identified internationalization as a determinant of the level of athletic performances. This level increased more in events that witnessed more important shifts in market shares (dynamic internationalization or competitiveness) and where dominance by a subset of countries (static internationalization) decreased. This internationalization clearly affects performances in men's athletics (as the performance has clearly gone up since 1984), but not in women's athletics. Here the general level of women's athletics has actually decreased.  相似文献   

14.
为了进一步探索NBA球员薪酬的影响因素,以期为中国篮球职业联赛发展提供借鉴,选取了NBA联赛2009/2010—2018/2019赛季997名球员为研究对象,通过构建混合线性模型,得出:(1)影响NBA球员薪酬的因素是多方面的,其中国籍、学历、年龄、身体形态、选秀名次、比赛经验以及竞技表现(上场时间、效率值)对球员薪酬产生明显的影响;(2)NBA球员的胜率以及能否进入季后赛对其薪酬无显著影响;(3)NBA球员的薪酬也会受到不同赛季的影响。  相似文献   

15.
This article compares East Germany's Cold War-era approach to doping to that of the USA's in terms of their respective impacts on medical risk. Although deserving of criticism on many levels, the GDR doping programme featured a number of safeguards designed to minimise medical dangers. Unlike their East German counterparts, American governmental units were not directly involved in the administration of performance-enhancing substances. The US approach to doping was not ideal in terms of medical risk, however. As a result of the country's regulatory approach to doping, the country's athletes frequently turned to black market sources for doping agents. It was also relatively common for American athletes to use performance-enhancing drugs without the benefit of medical supervision. The US approach to doping was in these ways inferior to that of East Germany's on the subject of medical risk.  相似文献   

16.
The emergence of India as the financial and spiritual heart of world cricket in the 1990s is intrinsically linked to India's satellite TV revolution in the same period. The 1990s began with just one Indian television channel – the state owned Doordarshan – but by 2006, Indian viewers were remote-controlling their way through more than 300 private satellite television channels. While the reasons for this phenomenal growth of the television industry are varied and complex, cricket has played a central role in the story. This paper will outline Indian satellite television's linkages with cricket and what they mean for notions of identity and expressions of Indian nationhood. In particular, it focuses on India's 24-hour television news networks – there are more than 50 in 14 languages. Unlike any other country in the world, the Indian television news industry has consciously ridden on cricket's shoulders to such an extent that by 2006, cricket-oriented programming accounted for the greatest expenditure in news gathering and the greatest visibility across most news channels. Television producers looked towards cricket because of its indelible link with what might be called Indian-ness, but their focus on the game, in turn, substantially redefined and reinforced these linkages.  相似文献   

17.
《反兴奋剂条例》是我国反兴奋剂法律法规体系的主干。近年来,国际层面反兴奋剂治理的理念、规则、机构、权责都发生了较大变化,国内新修订的《中华人民共和国体育法》《中华人民共和国刑法修正案(十一)》在兴奋剂争端解决、入刑等方面也有新的发展,为我国反兴奋剂工作的法治化、制度化、规范化提供了有力支撑,指明了努力方向。我国《反兴奋剂条例》的修订,应适应当前反兴奋剂工作的需要,构建我国更为完善的反兴奋剂治理和争端解决体系,与国际反兴奋剂治理体系有效衔接,进而推进我国更多地参与国际反兴奋剂治理,提升在反兴奋剂和体育治理中的话语权。建议在《反兴奋剂条例》(修订草案)中明确兴奋剂概念、细化兴奋剂违规类型与违规处罚方式、增加争端解决机制。  相似文献   

18.
Abstract

In this holistic review of cycling science, the objectives are: (1) to identify the various human and environmental factors that influence cycling power output and velocity; (2) to discuss, with the aid of a schematic model, the often complex interrelationships between these factors; and (3) to suggest future directions for research to help clarify how cycling performance can be optimized, given different race disciplines, environments and riders. Most successful cyclists, irrespective of the race discipline, have a high maximal aerobic power output measured from an incremental test, and an ability to work at relatively high power outputs for long periods. The relationship between these characteristics and inherent physiological factors such as muscle capilliarization and muscle fibre type is complicated by inter-individual differences in selecting cadence for different race conditions. More research is needed on high-class professional riders, since they probably represent the pinnacle of natural selection for, and physiological adaptation to, endurance exercise. Recent advances in mathematical modelling and bicycle-mounted strain gauges, which can measure power directly in races, are starting to help unravel the interrelationships between the various resistive forces on the bicycle (e.g. air and rolling resistance, gravity). Interventions on rider position to optimize aerodynamics should also consider the impact on power output of the rider. All-terrain bicycle (ATB) racing is a neglected discipline in terms of the characterization of power outputs in race conditions and the modelling of the effects of the different design of bicycle frame and components on the magnitude of resistive forces. A direct application of mathematical models of cycling velocity has been in identifying optimal pacing strategies for different race conditions. Such data should, nevertheless, be considered alongside physiological optimization of power output in a race. An even distribution of power output is both physiologically and biophysically optimal for longer ( >4km) time-trials held in conditions of unvarying wind and gradient. For shorter races (e.g. a 1km time-trial), an‘all out’ effort from the start is advised to‘save’ time during the initial phase that contributes most to total race time and to optimize the contribution of kinetic energy to race velocity. From a biophysical standpoint, the optimum pacing strategy for road time-trials may involve increasing power in headwinds and uphill sections and decreasing power in tailwinds and when travelling downhill. More research, using models and direct power measurement, is needed to elucidate fully how much such a pacing strategy might save time in a real race and how much a variable power output can be tolerated by a rider. The cyclist's diet is a multifactorial issue in itself and many researchers have tried to examine aspects of cycling nutrition (e.g. timing, amount, composition) in isolation. Only recently have researchers attempted to analyse interrelationships between dietary factors (e.g. the link between pre-race and in-race dietary effects on performance). The thermal environment is a mediating factor in choice of diet, since there may be competing interests of replacing lost fluid and depleted glycogen during and after a race. Given the prevalence of stage racing in professional cycling, more research into the influence of nutrition on repeated bouts of exercise performance and training is required.  相似文献   

19.
Abstract

In this study, we assessed the longitudinal effects of social-cognitive mechanisms on the self-reported use of doping substances and supplements among Italian high school students. In total, 1232 students completed questionnaires measuring various psychological factors hypothesized to influence students' intention to use substances. Three months later, 762 of the students completed the same questionnaires a second time and also reported their use of substances during the time between assessments. Overall, the percentages of students using doping substances (2.1%) or supplements (14.4%) were consistent with values reported in the literature. Analysis of the data showed that adolescents' intention to use doping substances increased with stronger attitudes about doping, stronger beliefs that significant others would approve of their use, a stronger conviction that doping use can be justified, and a lowered capacity to resist situational pressure or personal desires. In turn, stronger intentions and moral disengagement contributed to a greater use of doping substances during the previous 3 months. Doping use was also correlated significantly to supplementation. In conclusion, our results provide novel information about some of the psychological processes possibly regulating adolescents' use of doping substances and supplements. The results also highlight possible areas for future study and intervention, focusing on the prevention of adolescents' substance use.  相似文献   

20.
职业篮球运动员工会是维护职业篮球运动员合法权益的重要组织。鉴于实践领域的具体矛盾冲突,在中国男子篮球职业联赛(CBA)职业化发展趋向倒推劳资结构调整以及劳资纠纷中运动员的有效救济途径阙如的背景下,我国职业篮球运动员工会的建立具有现实必要性。从建构职业篮球劳资关系三方机制的维度来看,中国篮球协会改革已经进入深水区,CBA联盟已基本具备资方联盟形态,由中国篮球协会牵头组建独立的运动员工会是弥补我国职业篮球劳资关系三方机构结构缺失的关键之举,同时该建构模式是兼具合法性与现实性的可行之策。美国职业篮球运动员工会(NBPA)的建立为我国运动员工会的建立提供了可资参考的域外经验,应结合我国本土实际进行选择判断,应当明确独立性与渐进式是我国职业篮球运动员工会应具备的本质属性。  相似文献   

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