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Home advantage is well documented for professional baseball, basketball and ice hockey in North America. One of the possible causes of this advantage is familiarity with the local playing facility. This was investigated and quantified in an analysis of 37 teams moving to new stadiums, but in the same city, from 1987 to 2001. Home advantage during the first season in a new stadium after the move was significantly less than home advantage in the final season in the old stadium (P= 0.011). The reduction was evident in all three sports. Possible confounding factors, such as crowd size and crowd density, were considered but did not appear to have an effect. It is estimated that about 24% of the advantage of playing at home maybe lost when a team relocates to a new facility.  相似文献   

3.
赛制的改革和变化是最能反映一项运动是否能够与时俱进的标准。对于电子竞技的项目来说,除了游戏本身的升级和规则变更以外,一个比赛的赛制也是反映自己特点的最鲜明的地方。对于PGL来说,这种繁杂的赛制就是自己轻易不会更改的特色。但对于WC3L和NGL来说,则是到了非变不可的时候了。变多少?怎么变?看了赛季初比赛的朋友也会给出自己的理解,唯一一点确定的就是,War3还活着,而且活得很健康。  相似文献   

4.
《电子竞技》2009,(4):23-23
赛制的改革和变化是最能反映一项运动是否能够与时俱进的标准。对于电子竞技的项目来说,除了游戏本身的升级和规则变更以外,一个比赛的赛制也是反映自己特点的最鲜明的地方。对于PGL来说,这种繁杂的赛制就是自己轻易不会更改的特色。但对于WC3L和NGL来说,则是到了非变不可的时候了。变多少?怎么变?看了赛季初比赛的朋友也会给出自己的理解,唯一一点确定的就是,war3还活着,而且活得很健康。  相似文献   

5.
《Sport Management Review》2015,18(2):308-316
Organisational performance has become an imperative management function within the non-profit sport context as increased pressure is placed on these organisations to provide a quality service to stakeholders in an accountable and transparent manner. The case presented here examines the issue of developing and implementing a robust performance management tool that can potentially help national sport organisation managers with the multitude of performance challenges now facing these organisations. The theoretical underpinnings of a performance management tool are presented followed by background information to a fictional national sport organisation (Racquetball Australia) and views from the CEO of the organisation in relation to the topic of performance management. The case is written from a fictional perspective so that instructors may adapt the case to suit the geographical context in which the class is taking place.  相似文献   

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Purpose

Previous research demonstrating that specific performance outcome goals can be achieved in different ways is functionally significant for springboard divers whose performance environment can vary extensively. This body of work raises questions about the traditional approach of balking (terminating the takeoff) by elite divers aiming to perform only identical, invariant movement patterns during practice.

Method

A 12-week training program (2 times per day; 6.5 hr per day) was implemented with 4 elite female springboard divers to encourage them to adapt movement patterns under variable takeoff conditions and complete intended dives, rather than balk.

Results

Intraindividual analyses revealed small increases in variability in the board-work component of each diver's pretraining and posttraining program reverse-dive takeoffs. No topological differences were observed between movement patterns of dives completed pretraining and posttraining. Differences were noted in the amount of movement variability under different training conditions (evidenced by higher normalized root mean square error indexes posttraining). An increase in the number of completed dives (from 78.91%–86.84% to 95.59%–99.29%) and a decrease in the frequency of balked takeoffs (from 13.16%–19.41% to 0.63%–4.41%) showed that the elite athletes were able to adapt their behaviors during the training program. These findings coincided with greater consistency in the divers' performance during practice as scored by qualified judges.

Conclusion

Results suggested that on completion of training, athletes were capable of successfully adapting their movement patterns under more varied takeoff conditions to achieve greater consistency and stability of performance outcomes.  相似文献   

8.
Abstract

This study describes the changes which occurred in the instructional ecology of a boys' physical education class with a change of teacher. Moreover, it examines the critical incidences which promoted and inhibited that teacher's attempts to change the accountability system of the class from one of attendance and minimal participation to one of performance quality. Twenty-two eighth and ninth grade boys participated in a 6-week program of physical activity with the researcher as the new teacher. Through an action research methodology, using the teacher's reflective accounts of lessons together with formal and informal interviews with the students, it was determined that three factors were critical in the change process: the students' previous history with the subject, the nature of the set tasks, and the emotional climate of the class.  相似文献   

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In sailing regattas, the actions of sailboats are to meet, overlap, pursue, pass, anti-collide, and defend. The aerodynamic performance of a sail based on a numerical simulation method is reported in this study. The parameters affecting the sail’s aerodynamic force coefficients, namely sailing angle, attack angle, mast shape, pitch angle, and camber ratio, are analyzed. From the results, basic principles and corresponding tactics of sail trimming are discussed and recommended for the start, during the windward, running, and leeward legs, before the finish, and near the marks. Sailors in the regatta should decrease the interaction of air flows around the sail to increase the lift force. The sailing angle, attack angle, pitch angle, and camber ratio should be adjusted to the appropriate degree to speed the boat when it is balanced. Sail trimming tactics have been practiced by professional sailors in regattas during which they can be scientifically supervised to compete against each other at Olympic Games.  相似文献   

11.
高校田径运动会管理系统网络化设计   总被引:1,自引:0,他引:1  
张来明 《山东体育科技》2003,25(2):27-29,26
根据普通高校学生和教工田径运动会的特点,用Visual Basic和SOL Sever设计高校田径运动会网络管理系统。依据高校田径运动会管理的一般原则和程序,采用灵活的界面设计,系统具有可操作性强易于理解掌握的特点。  相似文献   

12.
Sport scientists have devoted relatively little attention to soccer penalty kicks, despite their decisive role in important competitions such as the World Cup. Two possible kicker strategies have been described: ignoring the goalkeeper action (open loop) or trying to react to the goalkeeper action (closed loop). We used a paradigm simulating a penalty kick in the laboratory to investigate the dynamics of the closed-loop strategy in these controlled conditions. The probability of correctly responding to the simulated goalkeeper motion as a function of time available followed a logistic curve. Kickers on average reached perfect performance only if the goalkeeper committed him or herself to one side about 400 ms before ball contact and showed chance performance if the goalkeeper motion occurred less than 150 ms before ball contact. Interestingly, coincidence judgement--another aspect of the laboratory responses--appeared to be affected for a much longer time (> 500 ms) than was needed to correctly determine laterality. The present study is meant as groundwork for experiments in more ecological conditions applicable to kickers and goalkeepers.  相似文献   

13.
The effect of practice on predicting elbow flexion movement time was studied. Participants (N = 18) performed 400 elbow flexion trials to a target in the horizontal plane. The trials were distributed equally over four sessions. The goal was to decrease the movement time (MT) for the same degree of accuracy. The electromyographic (EMG) activity of the biceps and triceps brachii was monitored with standard Beckman Ag/AgCl surface electrodes. The EMG measures formed two variable sets within one prediction equation. One variable set was composed of the onset of muscle activity relative to the start of movement (motor time) and the duration of muscle activity. The other variable set consisted of the mean amplitude value of the entire burst and of the first 30 ms (Q30) of activity. As the maximal speed of limb movement increased, the duration of muscle activity (motor time and EMG duration) decreased, and the magnitude of muscle activity (MAV and Q30) increased. Most of the change in the duration of muscle activity occurred in Session 1, while the magnitude of muscle activity continued to increase until Session 3. Multiple regression analysis revealed a cooperative strategy between the magnitude and duration of muscle activity. Early in learning, participants adjusted the magnitude of muscle activity to increase limb movement speed. As practice continued, alterations in the duration of muscle activity became more important, while the magnitude changes were less involved. Late in learning, both dimensions of muscle activity were used to decrease MT. We suggest that the interplay between the magnitude and duration of muscle activity may be due to: (a) cognitive factors related to the division of attention in a motor skill, (b) an increase in the frequency of motor unit firing that affects both dimensions of muscle activity, or (c) some combination of (a) and (b).  相似文献   

14.
This study involved a theoretical and an experimental investigation of the direct free kick in soccer. Our aim was to develop a mathematical model of the ball's flight incorporating aerodynamic lift and drag forces to explore this important 'set-play'. Trajectories derived from the model have been compared with those obtained from detailed video analysis of experimental kicks. Representative values for the drag and lift coefficients have been obtained, together with the implied orientation of the ball's spin axis in flight. The drag coefficient varied from 0.25 to 0.30 and the lift coefficient from 0.23 to 0.29. These values, used with a simple model of a defensive wall, have enabled free kicks to be simulated under realistic conditions, typical of match-play. The results reveal how carefully attackers must engineer the dynamics of a successful kick. For a central free kick some 18.3 m (20 yards) from goal with a conventional wall, and initial speed of 25 m·s?1, the ball's initial elevation must be constrained between 16.5° and 17.5° and the ball kicked with almost perfect sidespin.  相似文献   

15.
Eight cyclists were photographed with a digital camera for three trials while positioned on their own bicycle wearing their helmet. The positions were different from each other and described as hands on the brake hoods, hands below the curve of the brake hoods on the handlebars, and using aerobars. Twenty-four trials were digitized by two different individuals three times to estimate the inter- and intra-rater reliability of the method. The intraclass correlation coefficient (p < .05) value for the intra-rater (test–retest) reliability was .993, and for inter-rater consistency, it was .976. There were significant differences (p < .05) between digitizers and between trials, apparently due to a learning effect that disappeared by the third trial. Due to small differences between digitizers and trials, caution is recommended when considering the use of this method.  相似文献   

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The purpose of the present study was to determine the reliability of a 5km run test on a motorized treadmill. Over three consecutive weeks, 12 well-trained runners completed three 5km time trials on a treadmill following a standardized warm-up. Runners were partially-blinded to their running speed and distance covered. Total time to complete the run was recorded for analysis of reliability. The highest intraclass correlation coefficient between trials for 5km time trial (TT) time was .99 (90% confidence intervals [CI]; .96–1.00, very high), which occurred between trials 2 and 3. The lowest typical error of measurement (expressed as a coefficient of variation percentage [CV%] and as an absolute value in seconds) also occurred between trials 2 and 3, and was 1.0% and 10.9 seconds, respectively. The testing protocol performed on a motorized treadmill in the current study is reproducible in well-trained runners following a single trial, making it a reliable method for monitoring running performance.  相似文献   

18.
Sport scientists have devoted relatively little attention to soccer penalty kicks, despite their decisive role in important competitions such as the World Cup. Two possible kicker strategies have been described: ignoring the goalkeeper action (open loop) or trying to react to the goalkeeper action (closed loop). We used a paradigm simulating a penalty kick in the laboratory to investigate the dynamics of the closed-loop strategy in these controlled conditions. The probability of correctly responding to the simulated goalkeeper motion as a function of time available followed a logistic curve. Kickers on average reached perfect performance only if the goalkeeper committed him or herself to one side about 400 ms before ball contact and showed chance performance if the goalkeeper motion occurred less than 150 ms before ball contact. Interestingly, coincidence judgement?-?another aspect of the laboratory responses?-?appeared to be affected for a much longer time (>500 ms) than was needed to correctly determine laterality. The present study is meant as groundwork for experiments in more ecological conditions applicable to kickers and goalkeepers.  相似文献   

19.
Expert performers in striking sports can hit objects moving at high speed with incredible precision. Exceptionally well developed anticipation skills are necessary to cope with the severe constraints on interception. In this papr we provide a review of the empirical evidence regarding expert interception in striking sports and propose a preliminary model of expert anticipation. Central to the review and the model is the notion that the visual information used to guide the sequential phases of the striking action is systematically different between experts and nonexperts. Knowing the factors that contribute to expert anticipation, and how anticipation may guide skilled performance in striking sports, has practical implications for assessment and training across skill levels.  相似文献   

20.
While Turkey is mostly a Muslim country, officially it is a secular country; traditional gender roles are still maintained, and homosexuality is a taboo subject. The Turkish sporting world is no exception; it also excludes and ignores the existence of homosexuals and homosexuality. Using a single case study, this study aimed to contribute to fill the gap in the understudied subject of homosexuality in physical education (PE) and sports literature through investigating the experiences of a gay male Turkish PE and sports major. The respondent was aged 25 and a fourth-year undergraduate student at the time. Purposive sampling was used to select the respondent based on his willingness to participate in the study and a semi-structured interview allowed for data to be collected regarding being gay in Turkey, and in particular in the PE and sports environment. The four major themes derived from the analysed interview data were (1) conflicting feelings about coming out of the closet, (2) life in the Turkish community, (3) life in a PE and sports department and (4) perceived roots of homophobia. The findings indicated that the respondent's disclosure of his sexual orientation to friends resulted in positive reactions; however, he still hesitates to acknowledge his homosexuality publicly. Traditional gender roles, misconceptions about homosexuality and homosexuals and religion were perceived as the most influential factors for homophobic attitudes and behaviour in Turkish society. His experiences in Turkey's world of PE and sports were rife with homophobia.  相似文献   

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