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1.
Boxing, weight-lifting, wrestling, and judo are graded events in that opponents are matched by weight. If protection were to be denied by removing this restriction such sports would overwhelmingly favour the heavyweights. Data on Olympic winners show that many running and jumping events are seriously biased in favour of the very tall. It is suggested that the rules of these events should be revised to include a grading by height. This would remedy an element of unfairness in many athletic contests, beginning at school.  相似文献   

2.
The aim of the study was to determine which of the observed variables differentiate mostly the successful (Olympic Games contenders) from the less successful rowers (Internationally competitive rowers) and in order for that anthropometric and physiological profile of elite Croatian heavyweight rowers was assessed. Twenty nine national rowing champions were divided into two groups according to their international competitive achievements. Physiological characteristics were assessed during a continuous progressive rowing ergometer test. Differences were determined using the independent t-test with Bonferroni corrections. Successful rowers had somewhat larger values of almost all of the observed lengths, widths and girths (exceptions: chest and thigh girth). In addition, their maximal oxygen uptake was significantly higher (5.51 +/- 0.40 L/min vs. 5.16 +/- 0.39 L/min; p < 0.05) as was their power output at anaerobic threshold (346.3 +/-17.9 W vs. 319.2 +/- 20.1 W; p < 0.01). Less successful Croatian rowers should target their training in the upcoming years towards increasing, primarily, maximal oxygen uptake and power output at anaerobic threshold.  相似文献   

3.
World records (WR) in sports illustrate the ultimate expression of human integrated muscle biology, through speed or strength performances. Analysis and prediction of man's physiological boundaries in sports and impact of external (historical or environmental) conditions on WR occurrence are subject to scientific controversy. Based on the analysis of 3263 WR established for all quantifiable official contests since the first Olympic Games, we show here that WR progression rate follows a piecewise exponential decaying pattern with very high accuracy (mean adjusted r(2) values = 0.91+/-0.08 (s.d.)). Starting at 75% of their estimated asymptotic values in 1896, WR have now reached 99%, and, present conditions prevailing, half of all WR will not be improved by more than 0,05% in 2027. Our model, which may be used to compare future athletic performances or assess the impact of international antidoping policies, forecasts that human species' physiological frontiers will be reached in one generation. This will have an impact on the future conditions of athlete training and on the organization of competitions. It may also alter the Olympic motto and spirit.  相似文献   

4.
The aim of this study was to investigate the seasonal behaviour of the plasma free testosterone: cortisol ratio (FTCR) and to relate hormonal changes to daily training volume and performance parameters on a rowing ergometer in elite female rowers. During 9 months of training preceding the 1988 Olympic Games the resting values of the FTCR in six elite female rowers were regularly (ten times) studied. Daily training volume was analysed in terms of rowed distance (l rowad) and time (t). In addition, two performance parameters, the power at 4.0 mmol·l–1 lactate concentration in the blood and the maximal power, were determined by a test on a rowing ergometer. The results indicated that the mean FTCR test value did not differ significantly from the level of the initial test or from the mean value of the directly preceding test. A significant negative correlation (r=–0.98, P<0.01) between FTCR and l rowed was found in a period i.e. at a training camp, when there was a sudden increase in training volume. When FTCR was related to t a significant positive correlation (r=0.88, P<0.05) was found only for the period at the training camp. Our data further suggested that the FTCR alone was not an adequate indicator for the anabolic/catabolic balance in elite female rowers. This finding was contrary to previous findings in elite male rowers. However, in training practice the FTCR seems useful as an indicator of the hormonal training status of elite female rowers when complemented with data about total and free testosterone, performance parameters and knowledge concerning cyclic variations of the FTCR.Both departments co-operate in the working group Janus Jongbloed Research Centre, Utrecht, The Netherlands  相似文献   

5.

Background/Aim

Strenuous endurance training required to participate in the highest sports level has been associated with deleterious effects on elite athletes'' health and cardiac abnormalities. We aimed to describe overall mortality and main causes of deaths of male French rowers participating in at least one Olympic Game (OG) from 1912 to 2012 in comparison with the French general population.

Methods

Identity information and vital status of French Olympic rowers were validated by National sources from 1912 to 2013 (study''s endpoint) among 203 rowers; 52 out of 255 (20.3%) were excluded because their vital statuses could not be confirmed. Main causes of deaths were obtained from the National registry from 1968 up to 2012. Overall and disease-specific mortalities were calculated through standardised mortality ratios (SMRs) with its 95% confidence intervals (CIs). The overall mortality was calculated for the whole rowers'' cohort (PT) and for two periods apart: (P1) including rowers from 1912 to 1936 OG, a cohort in which all rowers have deceased and (P2) considering rowers from 1948 to 2012 OG.

Results

Among the 203 rowers analysed, 46 died before the study''s endpoint, mainly from neoplasms (33%), cardiovascular diseases (21%) and external causes (18%). PT demonstrates a significant 42% lower overall mortality (SMR: 0.58, 95% CI: 0.43–0.78, p<0.001), P1 a 37% reduction (SMR: 0.63, 95% CI: 0.43–0.89, p = 0.009) and P2 a 60% reduction (SMR: 0.40, 95% CI: 0.23–0.65, p<0.001) compared with their compatriots. Mortality due to cardiovascular diseases is significantly reduced (SMR: 0.41, 95% CI: 0.16–0.84, p = 0.01) among rowers.

Conclusions

French Olympic rowers benefit of lower overall mortality compared with the French general population. Among rowers'' main causes of death, cardiovascular diseases are reduced in relation to their compatriots. Analytical studies with larger samples are needed to understand the reasons for such reductions.  相似文献   

6.
目的:通过对奥运会赛前6周运动员微循环血流储备能力的变化与常规机能指标关系的研究,探讨微循环血流储备能力用于运动员机能状态监控的可行性。方法:以国家赛艇队8名男子轻量级运动员为研究对象,每周一6:30-7:00在安静空腹状态下,指尖采血进行血红蛋白(Hb)、红细胞数量(RBC)、血尿素(BU)和血清肌酸激酶(CK)的测试,同时,训练负荷较大的两周以及奥运会前的两周分别进行静脉取血测试睾酮(T)和皮质醇(C);在相应的时间节点使用PeriFluxSystem 5000激光多普勒血流监测仪对运动员进行微循环血流储备能力测试。结果:运动员肱二头肌微循环血流储备能力与常规机能指标均呈现出一定的相关性,其中与T存在显著性正相关,(P <0.05),与Hb、C和T/C存在正相关,但不具有显著性(P > 0.05);与BU和CK存在负相关,且与BU的相关具有显著性(P < 0.05);结论:微循环血流储备能力在评价训练强度对机体疲劳积累的影响时更敏感,其的变化与常规生化指标变化特点具有一定的一致性,可在一定程度上作为运动员机能状态评价和疲劳程度判断的一项无创性指标。  相似文献   

7.

Background

The tobacco industry has long sought affiliation with major sporting events, including the Olympic Games, for marketing, advertising and promotion purposes. Since 1988, each Olympic Games has adopted a tobacco-free policy. Limited study of the effectiveness of the smoke-free policy has been undertaken to date, with none examining the tobacco industry’s involvement with the Olympics or use of the Olympic brand.

Methods and Findings

A comparison of the contents of Olympic tobacco-free policies from 1988 to 2014 was carried out by searching the websites of the IOC and host NOCs. The specific tobacco control measures adopted for each Games were compiled and compared with measures recommended by the WHO Tobacco Free Sports Initiative and Article 13 of the Framework Convention on Tobacco Control (FCTC). This was supported by semi-structured interviews of key informants involved with the adoption of tobacco-free policies for selected games. To understand the industry’s interests in the Olympics, the Legacy Tobacco Documents Library (http://legacy.library.ucsf.edu) was systematically searched between June 2013 and August 2014. Company websites, secondary sources and media reports were also searched to triangulate the above data sources.This paper finds that, while most direct associations between tobacco and the Olympics have been prohibited since 1988, a variety of indirect associations undermine the Olympic tobacco-free policy. This is due to variation in the scope of tobacco-free policies, limited jurisdiction and continued efforts by the industry to be associated with Olympic ideals.

Conclusions

The paper concludes that, compatible with the IOC’s commitment to promoting healthy lifestyles, a comprehensive tobacco-free policy with standardized and binding measures should be adopted by the International Olympic Committee and all national Olympic committees.  相似文献   

8.
We staged contests between convict cichlids (Cichlasoma nigrofasciatum)that were matched for size and gender to test the influenceof prior information and resource value on the duration andstructure of fights. The contestants were separated before thecontest by either clear or opaque dividers to allow or preventvisual assessment, respectively. Contests were shorter in the"clear" than in the "opaque" treatment, suggesting that visualassessment occurred. The duration of lateral display, a noncontactdisplay, was shorter in the clear than in the opaque treatment,but the treatments did not differ significantly in the durationof three contact displays (biting, mouth wrestling, and circling).These results are consistent with the hypothesis that lateraldisplay provides primarily visual information, probably aboutbody size, whereas the other behavior patterns provide primarilynonvisual information, probably about strength. Second contestsbetween the same pair of fish were shorter than first contests,suggesting that the information acquired during the first contestmade it easier to resolve the second. After the subordinatefish from the second contest was given access to a mate, itfought more persistently so that third contests were longerthan second contests. Our results support the predictions ofthe sequential assessment model.  相似文献   

9.
In sport events like Olympic Games or World Championships competitive athletes keep pushing the boundaries of human performance. Compared to team sports, high achievements in many athletic disciplines depend solely on the individual’s performance. Contrasting previous research looking for expertise-related differences in brain anatomy at the group level, we aim to demonstrate changes in individual top athlete’s brain, which would be averaged out in a group analysis. We compared structural magnetic resonance images (MRI) of three professional track-and-field athletes to age-, gender- and education-matched control subjects. To determine brain features specific to these top athletes, we tested for significant deviations in structural grey matter density between each of the three top athletes and a carefully matched control sample. While total brain volumes were comparable between athletes and controls, we show regional grey matter differences in striatum and thalamus. The demonstrated brain anatomy patterns remained stable and were detected after 2 years with Olympic Games in between. We also found differences in the fusiform gyrus in two top long jumpers. We interpret our findings in reward-related areas as correlates of top athletes’ persistency to reach top-level skill performance over years.  相似文献   

10.

Background

Despite the provision of maternity leave offered to mothers, many American women fail to take leave.

Methods

We developed an evidence-based maternity leave educational tool for working women in California using participatory design. We tested its short-term efficacy with a randomized controlled trial of pregnant English-speakers (n=155).

Results

Among intervention participants exposed to the tool, 65% reported that they learned something new; 38% were motivated to seek more information; and 49% said it helped them plan their maternity leave. Among participants who delivered at ≥ 37 weeks gestation and said the tool helped them plan their leave, 89% took more than one week of prenatal leave, a significantly higher proportion than among controls who did not receive the tool (64%, p=0.049). Other findings favored trial participants, but were not statistically significant in this small sample. More intervention participants took some prenatal leave (80%) vs. controls (74%, p=0.44). Among participants who had returned to work when surveyed (n=50), mean postnatal leave uptake was on average 1 week longer for intervention participants vs. controls (13.3 vs. 12.2 weeks, p=0.54).

Conclusions

The first-phase evaluation of this tool shows that it successfully informed women about maternity leave options, clarified complex regulations, encouraged women to seek further information and helped plan maternity leave. Compared to controls, trial participants who used the tool to plan their leave were far more likely to take prenatal leave close to term. Future evaluation of the tool when mediated by a health provider or employer is warranted.  相似文献   

11.
The alternative transportation strategy implemented during the 2008 Summer Olympic Games in Beijing provided an opportunity to study the impact of the control measures and weather conditions on air quality and asthma morbidity. An ecological study compared the 41 days of the Olympic Games (8 August–17 September 2008) to a baseline period (1–30 June). Also, in order to emphasize the impact of weather conditions on air quality, a pollution linking meteorological index (Plam) was introduced to represent the air pollution meteorological condition. Our study showed that the average number of outpatient visits for asthma was 12.5 per day at baseline and 7.3 per day during the Olympics—a 41.6% overall decrease. Compared with the baseline, the Games were associated with a significant reduction in asthma visits (RR 0.58, 95%CI: 0.52–0.65). At 16.5 visits per day, asthma visits were also significantly higher, during the pre-Olympic period (RR 1.32, 95% CI: 1.15–1.52). The study also showed that the RR of asthma events on a given day, as well as the average daily peak ozone concentration during the preceding 48–72 h, increased at cumulative ozone concentrations of 70 to 100 ppb and 100 ppb or more compared with ozone concentrations of less than 70 ppb (P < 0.05). We concluded that along with “good” weather conditions, efforts to reduce traffic congestion in Beijing during the Olympic Games were associated with a prolonged reduction in air pollution and significantly lower rates of adult asthma events. These data provide support for efforts to reduce air pollution and improve health via reductions in motor vehicle traffic.  相似文献   

12.
In Men's Artistic Gymnastics the current trend in elite high bar dismounts is to perform two somersaults in an extended body shape with a number of twists. Two techniques have been identified in the backward giant circles leading up to release for these dismounts (J. Biomech. 32 (1999) 811). At the Sydney 2000 Olympic Games 95% of gymnasts used the "scooped" backward giant circle technique rather than the "traditional" technique. It was speculated that the advantage gained from the scooped technique was an increased margin for error when releasing the high bar. A four segment planar simulation model of the gymnast and high bar was used to determine the margin for error when releasing the bar in performances at the Sydney 2000 Olympic Games. The eight high bar finalists and the three gymnasts who used the traditional backward giant circle technique were chosen for analysis. Model parameters were optimised to obtain a close match between simulated and actual performances in terms of rotation angle (1.2 degrees ), bar displacements (0.014 m) and release velocities (2%). Each matching simulation was used to determine the time window around the actual point of release for which the model had appropriate release parameters to complete the dismount successfully. The scooped backward giant circle technique resulted in a greater margin for error (release window 88-157 ms) when releasing the bar compared to the traditional technique (release window 73-84 ms).  相似文献   

13.
Human trade and transport is a major contributor to the global spread of invasive species and biodiversity change. Much of the focus on anthropogenic spread has been the movement of species between countries with far less attention being placed on the within country spread. For invasive arthropods, trade in ornamentals is a key contributor to global spread, but the role played by the transport of ornamentals within countries has been less well explored. In China, the hosting of major international events is an important expression of national and international pride and prestige. Hosting these is associated with the substantial use of landscaping to beautify the sites, all of which need to transport considerable numbers of plants to the event sites from various parts of China. To assess the consequences of this in terms of the spread of arthropod pests we sampled ornamental plants used to landscape the 29th Olympic Games in Beijing and the 16th Asia Games in Guangzhou. Plants used to landscape the Olympic Games were transported from ten provinces from across the eastern half of China. A total of 44 species of herbivorous arthropods belonging to six orders were recorded with eight species being new records for Beijing. Plants used at the 16th Asian Games came from five provinces. In total 32 species of arthropod herbivores belonging to six orders were recorded with four being new records for Guangdong province. Our results suggested that measures need to be considered to reduce the likelihood of invasive species spread when hosting major international events.  相似文献   

14.
The relationship between the dynamics of cardiorespiratory parameters of elite rowers determined in ergospirometer testing and their performance in 2000- and 6000-m Concept II rowing ergometer contests was analyzed. The analysis showed a strong correlation between sports results and physiological parameters, such as the maximal oxygen consumption in absolute units, oxygen consumption at the aerobic threshold and respiratory compensation point, fat-free body mass, maximum attainable power of performance, and powers at the aerobic threshold and respiratory compensation point, despite the substantial period of time between the contests and the functional ergospirometer tests.  相似文献   

15.
In this commentary, we describe two new protein structure prediction experiments being run in parallel with the CASP experiment, which together may be regarded as the 2000 Olympic Games of structure prediction. The first new experiment is CAFASP, the Critical Assessment of Fully Automated Structure Prediction. In CAFASP, the participants are fully automated programs or Internet servers, and here the automated results of the programs are evaluated, without any human intervention. The second new experiment, named LiveBench, follows the CAFASP ideology in that it is aimed towards the evaluation of automatic servers only, while it runs on a large set of prediction targets and in a continuous fashion. Researchers will be watching the 2000 protein structure prediction Olympic Games, to be held in December, in order to learn about the advances in the classical 'human-plus-machine' CASP category, the fully automated CAFASP category, and the comparison between the two.  相似文献   

16.
17.
The purpose of this study was to determine the relationship between attack time (AT) and skipping time (ST) during the 2007 Taekwondo World Championship and 2008 Beijing Olympic Games. A total of 22 matches (65 rounds, 13 semifinals, and 8 finals) from the World Championship and 23 matches (63 rounds, 22 rounds with 16 athletes each and 1 quarterfinal round) from the Olympic Games, both in the male category, were assessed using time-motion analysis. The AT was considered as the total time during which the athlete attacked or tried to attack, whereas ST was the total time without attempting to attack. The ratio of AT to ST was ~ 1:7 based on the data pooled from the 2 competitions. The AT/ST ratio was significantly lower for the World Championship than for the Olympic Games (p ≤ 0.05). In the Olympic Games, no consistent differences across weight divisions were found. However, during the World Championship, the heavier weight divisions (>78 kg) exhibited a lower average AT, lower summed AT, lower attack numbers (ANs)and higher average ST than lighter weight divisions (<58 kg, p ≤ 0.05). For both competitions, the ST was lower, and the ANs and AT/ST ratio were higher in round 3 than in round 1 or 2. In conclusion, the results of this study suggest that matches in the Olympic Games were less cadenced than in the World Championship, but that in both competitions, the intensity of the match increased in round 3. Practically, these data suggest that coaches need to structure Taekwondo training sessions in a manner that allows the work/pause ratio to mirror the physical demand imposed during competitions.  相似文献   

18.
The use of the data from various athletic sports for exercises in the interpretation of data is proposed, and accounts are given of two such exercises. The first looks at the relationship between time and distance in world records for men running. When the logarithm of the time is plotted against the logarithm of the distance a straight line is produced. Thefactors that govern the speeds at which various distances are run are discussed and the application of these to other sports and to animals other than man is briefly mentioned. The second exercise looks at anomalous performances by men running in the 1968 Olympic Games which took place at high altitude. It is shown that while the lowered air resistance increased the speeds in sprint events, and the lowered oxygen content slowed down speeds in long distance events, these were not the only factors involved in limiting speeds.

Among the advantages of the use of such data are that they are readily and easily available, that they are the result of a lengthy selection process involving many subjects, that they appeal to students interested in sport and that they can link courses in biology and physical education.  相似文献   

19.
R J Shephard 《CMAJ》1984,131(2):105-109
Air pollution may affect athletic performance. In Los Angeles, contaminants include carbon monoxide, ozone, peroxyacetylnitrate (PAN) and nitrogen oxides, whereas in older European cities, such as Sarajevo, "reducing smog" of sulfur dioxide is the main hazard. The carbon monoxide and ozone levels expected in Los Angeles this summer could affect the athletes'' performance in endurance events at the Olympic Games. Carbon monoxide may also impair psychomotor abilities, and PAN causes visual disturbances. The only likely physiologic consequence from reducing smog is an increase in the workload of the respiratory system and thus a decrease in endurance performance. While carbon monoxide has been blamed for myocardial infarctions, nitrogen oxides for pulmonary edema and sulfur dioxide for deaths due to respiratory failure, the only illnesses that are likely to be more frequent than usual among young athletes exposed to high levels of these pollutants are upper respiratory tract infections. Therapeutic tactics include the avoidance of pollution, the administration of oxygen, vitamin C and vitamin E, and general reassurance.  相似文献   

20.
R S Remis  E L Eason  R W Palmer  M Najjar  P Leclerc  F Lebel  M Fauvel 《CMAJ》1995,153(9):1271-1279
OBJECTIVE: To determine the seroprevalence and correlates of HIV infection in a subpopulation of women of childbearing age in Montreal. DESIGN: Anonymous unlinked seroprevalence study. SETTING: Pregnancy termination unit in a teaching hospital in Montreal. PARTICIPANTS: Women presenting for abortion from July 1989 to June 1993 who resided in Quebec and were not known to have HIV infection; 12,017 (99.6%) of 12,068 eligible women were included in the study. INTERVENTION: HIV antibody testing of serum left over from samples obtained for routine Rh typing; the same algorithm as for serodiagnostic testing, namely enzyme immunoassay (EIA) followed by confirmatory testing of repeatedly EIA-reactive samples, was used. OUTCOME MEASURES: HIV serostatus by age, marital status, region of residence (metropolitan Montreal versus other), country of birth and number of living children. RESULTS: Most (84.7%) of the subjects resided in metropolitan Montreal. The median age was 27.0 (range 13 to 50) years. The serum samples of 22 women were confirmed to be HIV positive, for an overall seroprevalence rate of 1.8 per 1000 (95% confidence interval 1.1 to 2.8). The seroprevalence rate did not vary significantly by age, marital status, region of residence or study year. However, it was strongly correlated with country of birth: Canada 0.16, Haiti 23.5, HIV-endemic countries other than Haiti 5.3 and non-HIV-endemic countries other than Canada 0.0 per 1000. The seroprevalence rate among women born in Haiti was 147 times higher than that among women born in Canada (p < 0.0001). Of the women born in Haiti the rate was 3.0 times greater among those who immigrated to Canada in 1985 or later than among those who immigrated earlier (p = 0.047). CONCLUSIONS: The results of this study indicate that the HIV seroprevalence rate among women in Montreal is strongly associated with country of birth, women born in HIV-endemic countries, especially Haiti, having the highest rate. These results will help in the development of policies regarding HIV antibody testing and prevention of HIV transmission in Quebec.  相似文献   

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