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1.
For a valid determination of a rower’s mechanical power output, the anterior–posterior (AP) acceleration of a rower’s centre of mass (CoM) is required. The current study was designed to evaluate the accuracy of the determination of this acceleration using a full-body inertial measurement units (IMUs) suit in combination with a mass distribution model. Three methods were evaluated. In the first two methods, IMU data were combined with either a subject-specific mass distribution or a standard mass distribution model for athletes. In the third method, a rower’s AP CoM acceleration was estimated using a single IMU placed at the pelvis.

Experienced rowers rowed on an ergometer that was placed on two force plates, while wearing a full-body IMUs suit. Correspondence values between AP CoM acceleration based on IMU data (the three methods) and AP CoM acceleration obtained from force plate data (reference) were calculated. Good correspondence was found between the reference AP CoM acceleration and the AP CoM accelerations determined using IMU data in combination with the subject-specific mass model and the standard mass model (intraclass correlation coefficients [ICC] >?0.988 and normalized root mean square errors [nRMSE]?3.81%). Correspondence was lower for the AP CoM accelerations determined using a single pelvis IMU (0.877?Based on these results, we recommend determining a rower’s AP CoM acceleration using IMUs in combination with the standard mass model. Finally, we conclude that accurate determination of a rower’s AP CoM acceleration is not possible on the basis of the pelvis acceleration only.  相似文献   

2.
This article examines the social forces underlying FIFAgate. Why do corrupt practices, which are often highly consolidated or even institutionalized, suddenly become scandalous? What is a scandal? Why did FIFA fall into crisis in 2015 and not before? To answer these questions, it is necessary to look at the sequence of thrusts and parries between all the parties involved. Our analysis embraces the notion that social processes are based on relationships in order to provide insights into why and how denunciations can lead to long-tolerated corrupt practices suddenly becoming compromising enough to force an organization’s leaders to implement measures that would have previously been unimaginable. We use multiple sources to examine the emergence of FIFAgate and the way FIFA overcame previous critical situations, describing how FIFA neutralized earlier allegations and developed a remarkable ‘resilience’ to scandal. Finally, we analyse the successive mobilizations whose domino effect led to the emergence of FIFAgate and the measures FIFA took to contain the scandal. Our research enabled us to draw up a new theoretical model for analysing corruption scandals.  相似文献   

3.
《Sport Management Review》2014,17(4):507-519
The purpose of this article is to contribute to the understanding of the emergence and change in institutional logics by analyzing the theorization (e.g., Greenwood, Suddaby, & Hinings, 2002) of a new and distinctly “different” practice in Swedish voluntary sport: drive-in sport. The article builds on data from 29 interviews with key actors involved in the organizing of drive-in sport in four municipalities. The findings show that two problems were constructed to legitimize drive-in sport: norm-breaking behavior displayed by youth during weekend nights, and organized sport's failure to live up to a sport-for-all ideal. The findings also show that it is perceived that in order for drive-in sport to be the solution to both these problems, the activities need to be arranged in a particular way. The findings are discussed in relation to recent developments in Swedish organized sport as an institutional context. Additionally, the discussion puts forth the value of the theorization concept in terms of furthering our understanding of the social-constructionist interpretive processes that underpin the broader processes of change documented in previous sport-related studies of change in institutional logics.  相似文献   

4.
In this essay, I defend sport as a (mere) hobby in contrast to sport as a ‘mutual quest for excellence through challenge’. With the assistance of ideas found in the novel Don Quixote, I raise questions about the clarity, merit, and sufficiency of the quest-for-excellence apologetic. I employ arguments made by James and Dewey to support my alternate defense of sporting activity as a hobby, that is, as ‘the gentle pursuit of a modest competence’. Based on the work of Wu, my defense stands as both a philosophic argument and a cultural critique.  相似文献   

5.
The following research approximated how the central nervous system of Paralympic wheelchair athletes resolve kinematic redundancies during upper-limb movements. A multibody biomechanical model of a tetraplegic Paralympic athlete was developed using subject-specific body segment parameters. The angular joint kinematics throughout a specified Paralympic sport movement (i.e., wheelchair curling) were experimentally measured using inertial measurement units. The motor control system of the Paralympian was mathematically modelled and simulated using forward dynamics optimization. The predicted kinematics from different optimization objective functions (i.e., minimizing resultant joint moments, mechanical joint power, and angular joint velocities and accelerations) were compared with those experimentally measured throughout the wheelchair curling movement. Of the optimization objective functions under consideration, minimizing angular joint accelerations produced the most accurate predictions of the kinematic trajectories (i.e., characterized with the lowest overall root mean square deviations) and the shortest optimization computation time. The implications of these control findings are discussed with regards to optimal wheelchair design through predictive dynamic simulations.  相似文献   

6.
The aim of this study was to analyse the characteristics of the asymmetries in the dominant and non-dominant limbs when kicking stationary and rolling balls. Ten experienced Brazilian amateur futsal players participated in this study. Each participant performed kicks under two conditions (stationary ball vs. rolling ball) with the dominant and non-dominant limbs (five kicks per condition per limb). We analysed the kicking accuracy, ball and foot velocities, angular joint displacement and velocity. The asymmetry between the dominant and non-dominant limbs was analysed by symmetry index and two-way repeated measures ANOVA. The results did not reveal any interaction between the condition and limb for ball velocity, foot velocity and accuracy. However, kicking with the dominant limb in both kicks showed higher ball velocity (stationary ball: dominant – 24.27 ± 2.21 m · s?1 and non-dominant – 21.62 ± 2.26 m · s?1; rolling ball: dominant – 23.88 ± 2.71 m · s?1 and non-dominant – 21.42 ± 2.25 m · s?1), foot velocity (stationary ball: dominant – 17.61 ± 1.87 m · s?1 and non-dominant – 15.58 ± 2.69 m · s?1; rolling ball: dominant – 17.25 ± 2.26 m · s?1 and non-dominant – 14.77 ± 2.35 m · s?1) and accuracy (stationary ball: dominant – 1.17 ± 0.84 m and non-dominant – 1.56 ± 1.30 m; rolling ball: dominant – 1.31 ± 0.91 m and non-dominant – 1.97 ± 1.44 m). In addition, the angular joint adjustments were dependent on the limb in both kicks (the kicks with non-dominant limb showed lower hip external rotation than the kicks with the dominant limb), indicating that the hip joint is important in kick performance. In conclusion, the kicks with the non-dominant limb showed different angular adjustments in comparison to kicks with the dominant limb. In addition, kicking a rolling ball with the non-dominant limb showed higher asymmetry for accuracy, indicating that complex kicks are more asymmetric.  相似文献   

7.
Abstract

The main aim of this study was to determine the test–retest reliability of existing tests of health-related fitness. Participants (mean age 14.8 years, s = 0.4) were 42 boys and 26 girls who completed the study assessments on two occasions separated by one week. The following tests were conducted: bioelectrical impedance analysis (BIA) to calculate percent body fat, leg dynamometer, 90° push-up, 7-stage sit-up, and wall squat tests. Intra-class correlation (ICC), paired samples t-tests, and typical error expressed as a coefficient of variation were calculated. The mean percent body fat intra-class correlation coefficient was similar for boys (ICC = 0.95) and girls (ICC = 0.93), but the mean coefficient of variation was considerably higher for boys than girls (22.2% vs. 12.2%). The boys' coefficients of variation for the tests of muscular fitness ranged from 9.0% for the leg dynamometer test to 26.5% for the timed wall squat test. The girls' coefficients of variation ranged from 17.1% for the sit-up test to 21.4% for the push-up test. Although the BIA machine produced reliable estimates of percent body fat, the tests of muscular fitness resulted in high systematic error, suggesting that these measures may require an extensive familiarization phase before the results can be considered reliable.  相似文献   

8.
ABSTRACT

Sport events that depend upon natural landscapes tend to draw athletes from urban centres to peripheral areas. In doing so these events function as tourist attractions but little is known about the way participating athletes understand these places. This study explores the ways that one type of sport traveller (i.e. ultramarathon runners) understands the host destination (Grande Cache, Canada) as a place of training and competition. A volunteer employed photography data collection method was used along with an inductive thematic analysis. Four themes emerged including place as: (a) landscape, (b) sport competition, (c) community, and (d) an introspective self-portrait. First, under the landscape theme runners saw place as sublime nature during the training camp (TC) and a terrain to be conquered during the race. Second, the sport competition theme reflected place as the event with the competition being the filter through which all other aspects of the setting were understood. Third, the setting was characterized as a place of community that fostered social connection and celebration. Finally, the introspective self-portrait theme focused on the runners themselves as they centred their identity within the setting. While landscape was a dominant theme during the TC visit, the sport competition and community themes became more salient during the competition weekend. The introspective self-portrait theme was strong during both visits. Study findings suggest that runners were attached to the setting through ‘place identity’ in addition to their dependence on it to facilitate the ultramarathon event.  相似文献   

9.
The first goal of this paper is to reply to a number of criticisms levied by Gunnar Breivik and Robert L. Simon against an account of sporting skills I published almost 20 years ago in which I distinguished between constitutive and restorative skills and examined their normative significance. To accomplish this goal, I first summarize my characterization and classification of skills and then detail the criticisms. After responding to the latter, and thus reconsidering and hopefully strengthening my account of skill in sport, I turn my attention to Scott Kretchmar and Tim Elcombe’s inquiry into the skills involved in competitive sport. These authors claim that contesting skills demand the same respect usually accorded to testing skills. The second goal of this paper is then to explore Kretchmar and Elcombe’s inquiry under the light of my reconsidered analysis of skill. I specifically advocate a plausible relationship, both in terms of their distinctive character and relative import, between testing and contesting skills and constitutive and restorative skills. In doing so, I seek to present a more comprehensive account of skill in non-competitive and competitive sport.  相似文献   

10.
Three physical activity questionnaires were validated against heart rate (HR) monitoring and motion accelerometer data. All three methods were carried out simultaneously on 62 children ages 4–8 years on 4 consecutive days. The questionnaires were filled in by the children's parents and teachers. The reported time of physical activity with moderate to vigorous intensity, expected to increase HR above 140 beats per minute (bpm), correlated with the time of HR ≥ 140 bpm and ≥ 150 bpm (r = .40, p < .01) and with the accelerometer score (r = .53, p < .0001). Correlation between the HR ≥ 140 bpm and accelerometer score was r = .45, p < .001, and between the HR ≥ 150 bpm and accelerometer score, it was r = .41, p < .01  相似文献   

11.
The article presents the most important results of metabolic (hormonal) study of dosed vibration training (DVT).The author presents vibrating training as an alternative to anabolic steroids on the basis of a comparison of the effectiveness of two types of stimulants - forbidden (doping) and non-medicinal non-invasive, relating to permitted physical means.The study shows that the level of androgens (testosterone),corticosteroids (cortisol), thyroid hormones (thyroxine,triiodothyronine),hormones of adenohypophysis (prolactin) increased under the effect of dosed vibration training.At the same time the level of hormones have no changes under traditional strength training with the use of a synthetic anabolic steroid (retabolil).For the duration of a limited period of time (1 microcycles) dosed vibrotraining causes a more powerful secretion of testosterone than the traditional strength training with the use of anabolic steroids. In this case,the overall time spent on the performance of the DVT training program comprises not more than 15% of the time spent on the traditional training exercises.  相似文献   

12.
Fundamental movement skills (FMS) competence is low in adolescent girls. An assessment tool for teachers is needed to monitor FMS in this demographic. The present study explored whether the Canadian Agility and Movement Skill Assessment (CAMSA) is feasible for use by physical education (PE) teachers of Australian Year 7 girls in a school setting. Surveys, focus group interviews, and direct observation of 18 specialist PE teachers investigated teachers’ perceptions of this tool. Results indicated that the CAMSA was usable in a real-world school setting and was considered a promising means to assess FMS in Year 7 girls. However, future iterations may require minor logistical alterations and further training for teachers on how to utilize the assessment data to enhance teaching practice. These considerations could be used to improve future design, application, and training of the CAMSA in school-based PE.  相似文献   

13.
Based on the moral problem of Maradona’s goal, known as the ‘Hand of God’, this essay presents a theoretical discussion using the perspective of figurational sociology of how game rules and moral rules are related. It does not aim to solve the moral dispute occasioned by actions like the ‘Hand of God’, but concentrates on a much more limited discussion (appealing to far fewer people) in which we strive to reach a proper sociological understanding. Indeed, we believe that the ‘Hand of God’ is a paradigmatic event for sociological reasoning. This is not to claim that sociology can give any final answers, but to suggest the opposite, namely that an understanding of the value of ‘hand goals’ can be very important for understanding the limits of sociological reason.  相似文献   

14.
Abstract

The generality of the variability in practice prediction, arising from Schmidt's schema theory (1975) of motor learning was tested on young children. More specifically, the structure of the variability session and its subsequent influence on transfer performance to a novel variation of the task was examined. Children tossed a weighted bean bag to a fixed target location. Three groups experienced variability in practice with four bean bags of varying weights (3, 4, 5, and 6 oz.); however, the trial-by-trial presentation of each weight was different for each group. One group received a random presentation of each weight from trial to trial while another experienced random presentations of a weight for blocks of three trials. The third variability group received blocked practice with six trials per block for each weight. All variability groups experienced the same amount of practice at each weight. A constant practice group experienced only a single weight. Following 24 practice trials, all subjects transferred outside the range of previous experience, receiving three trials with one of two possible test weights (2 oz. or 7 oz.). The results indicated that the variability group practicing with blocks of three trials at each variation led to superior performance at transfer to novel variations of the task. Overall, the experiment suggested that transfer performance for children is affected by the appropriate structure of variable practice which formulates the schemata for movement production.  相似文献   

15.
《Sport in History》2013,33(4):507-533
ABSTRACT

Various sport scholars have noted the transition of sports from amateur leisure pastimes to professionalised and globalised media sporting spectacles. Recent developments in darts offer an excellent example of these changes, yet the sport is rarely discussed in contemporary sports studies. The only sustained theoretical research on darts focuses primarily on the origins of the sport in its nostalgic form as a working-class, pub taproom pastime in England. This article critically examines the transformation of darts from a leisurely game to a professional sport between the 1970s and the 1990s. The change was enabled by the creation of the British Darts Organisation (BDO) and the introduction of television broadcasting, which together fed a continual process of professionalisation. Initially, this article discusses both the concept of professionalisation and similar developmental changes in a selection of English sports. Following this, via selected interviews, documentary analysis and archival information, the reasons behind the split in darts are explicated, shedding light on how the BDO did not successfully manage the transformation and the sport split into two governing bodies, from which the Professional Darts Corporation (PDC), the sport’s most successful organisation in the present day, has emerged to dominate the world of televised darts.  相似文献   

16.
This article reports on the ‘uptake’ dynamics and resultant manifestations of a school-based, incentive-driven, sport-for-development programme in the South African context of poverty. The ecological systems theory of Brofenbrenner, the theory of complexity and a neo-liberal framework underpin the social constructions of local meanings associated with programme participation and involvement. Thirty-nine primary schools in the Western Cape Province and four schools in the Eastern Cape Province deliver the programme in partnership with a local foundation. A representative sample of 15 schools, from rural and urban (township) impoverished communities, were selected for a baseline study. A mixed-method approach of the Sport-in Development Impact Assessment Tool was adapted to collect comparative data through 57 interviews, 35 focus group sessions (with 75 teachers and 176 learners) and 159 questionnaires completed by learners and 29 by school and cluster coordinators. Various models of implementation render nuanced findings at meso-, exo- and micro-levels, where interrelated systems, demographic and developmental influences translate into culturally informed sense-making, pro- and anti-social associative behaviours, praxis, institutional empowerment and status-conferring identity constructions. All partners promote a neoliberal approach that limits changes to the underlying social systems, and mostly promote individual and group attributes within the institutional and social world settings of participants.  相似文献   

17.
The influence of a 12-week-proprioceptive training on functional ankle stability was investigated in young speed skaters. Twenty-eight speed skaters were randomly divided into an intervention (n = 14) and into a control group (n = 14). A 15-min circle training was performed 5 times per week over a 12-week period. Measurements were taken prior to the training, after 6 and 12 weeks of training. Kinaesthesia was evaluated with the Isomed2000 in all movements of the ankle joint. Dynamic balance was tested with the Biodex Stability System at the stable level 8 and at the unstable level 2, measuring the overall stability index, the anterior/posterior and the medial/lateral scores. Static single-leg stance was evaluated using the Kistler force platform. Kinaesthesia of the intervention group improved significantly for plantarflexion of the right foot (P = 0.001) after 12 weeks. Dynamic balance showed significant differences in the intervention group after 12 weeks in comparison with the first measurement for each foot in the overall stability index, the anterior/posterior and the medial/lateral scores (P ≤ 0.017, respectively) at the unstable level 2. Functional ankle stability improved in terms of dynamic balance after 12 weeks of proprioceptive training. Therefore, inclusion of proprioceptive exercises in the daily training programme is recommended for young speed skaters.  相似文献   

18.
In this article, we investigate ‘no touch policies’ as a practical teacher concern that includes the body as a location, a source and a means in educational activity. We argue that to understand issues regarding physical touch within school practice we must conceive it as deeply associated with specific teaching techniques. Thus, the didactical challenge is not found in argumentations about the pro and cons of physical touch, but through analysis of how teachers handle student interaction and teaching intentions.

We consider teaching as a caring profession. Caring, as a practical teacher concern, requires wisdom regarding the right time to use bodily touch and to refrain from such use. This wisdom involves the ability to discern people’s needs, desires, interests and purposes in particular situations and act appropriately. From a body pedagogical perspective we approach intergenerational touch not only as a discursive and power-related question but as an essential tension in the intersection of the; ambiguity attendant to any intentional act such as teaching, the conflict between the ethics of care and the ethics of justice, and finally, the paradox of caring.

We draw on interviews with PE-teachers in Swedish primary, secondary and upper-secondary schools and analyses of a collection of techniques of bodily touch that are established and practiced with specific pedagogical purposes. The results shows PE teacher’s competence in handling different functions of intergenerational touch in relation to three different techniques of bodily touch; (1) Security touch, which is characterized by intentions to handle the fragile; (2) Denoting touch, which is characterized by intentions to handle learning content and (3) Relational touch, which is characterized by caring intentions. Each of these is of importance for the teachers in carrying out their call to teach and each of these relies on professional assessments whether or not it meets its intended purpose.  相似文献   


19.

This study tested a computer‐aided coaching analysis instrument (CAI) as part of an intervention strategy designed to modify verbal coaching behaviour. Four coaches were observed and analysed over 12 practice sessions. Coaches A, B and C received intervention feedback through CAI data, where selected behaviours were highlighted for discussion, and videotape images were used to illustrate discussion points. Coach D was provided with videotapes of his own performance and told to formulate and implement any of his own recommendations. The CAI data are primarily quantitative, so target values were created for the different dimensions of verbal behaviour. This benefited the coaches in interpreting their effectiveness and provided a reference to evaluate the magnitude of change. Written journals and audiotape recordings were also used to promote insight into the complexity of verbal behaviour and the ‘human factors’ (e.g. relationship with players, attitude to researcher) that affect behaviour modification.

Instructional effectiveness was assessed by time‐series analysis. There was evidence from each behaviour dimension that change can occur and be maintained as a result of exposure to the CAI intervention strategy. However, this is clearly contingent upon the coach understanding what is asked of him or her, and remains focused and committed to changing these particular behaviours. The analysis of Coach D's behavioural change suggests there are limitations to the sensitivity of discretionary viewing, as only two dimensions of behaviour were identified for, and resulted in, positive change. The results of this study provide support for Locke's (1984) contention that behaviour modification can occur by using data as direct feedback, as reinforcement and as information in the form of recommendations. However, the study also illuminates several factors that can negate the modification and maintenance of verbal coaching behaviour.  相似文献   

20.
In recent years studies have shown that sport can serve as a means towards conflict resolution. Since the time of British colonialism in the 1950s, and after its 1960 independence, Cyprus has experienced conflict between its two main communities – the Greek Cypriots and the Turkish Cypriots. The de facto division of the island in 1974 caused community isolation of the Turkish Cypriots who, for political reasons, have been excluded from participating in international sports competitions. This situation is more visible in football (soccer), the most popular sport on the island. In the last two years the two sides have been trying – so far unsuccessfully – to reinstate the Turkish Cypriots as members of the Official Cyprus Football Federation. This paper gives a background on what has preceded these attempts and discusses whether football is a means of reuniting the two communities, or whether it is used as a vehicle to further separation.  相似文献   

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