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Joanne MacLean, Laura Cousens and Martha Barnes

The Canadian Sport Policy advocates for increased interaction among sport organizations as a means to create a more efficient and effective system. The purpose of this study was to explore the existence and nature of linkages among a network of community basketball providers. Network theory focuses on the interconnections of organizations by considering the structural, social, and economic bonds of cooperative behavior. Quantitative data were collected via a questionnaire and analyzed using network software UCINET 6 to assess the numbers and types of linkages among a network of community basketball organizations (n = 10) in one geographical region. Next, in-depth, semistructured interviews were conducted with leaders from the organizations and from their provincial/national governing bodies (n = 11) to assess the barriers to linkages among these organizations. Results indicated a loosely coupled network, wherein issues of power and dependence, uncertainty, and the lack of managerial structures to initiate and manage linkages prevailed.

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Jenny McMahon and Kerry McGannon

This paper presents two meta-autoethnographies written by a former elite swimmer. In the first metaautoethnography, the swimmer revealed doubts in relation to details, emotions and inner-thoughts that she had included in her historical autoethnographic work. As a means of sorting and pondering these tensions and uncertainties, the swimmer explored cultural re-immersion as a possible additional element in the metaautoethnographic process. The second meta-autoethnography centers on the swimmer’s re-immersion into elite swimming culture. It was revealed how cultural re-immersion enabled the swimmer to better reflect on her historical autoethnographic work by providing a more conscientized, rational and reflexive voice. This research highlights how cultural re-immersion should be considered as an additional element in the metaautoethnographic process as it benefits both the author and also audience.

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Martin Gérin-Lajoie, Carol L. Richards and Bradford J. McFadyen

This article introduces a novel, ecological, obstructed walking paradigm. Gait adaptations to circumvent obstacles undergoing uncertain displacements, and the effect of revealing the obstacle’s action beforehand, were investigated in young adults. The personal space (PS) maintained during walking was quantified for the first time under different environmental factors including auditory distractions. Obstacle movement and its uncertainty resulted in gait adjustments aimed at gaining time to assess the situation. Early gait adaptations and constant clearances around the obstacle suggest that anticipation and preplanning are involved in such navigational tasks. Participants systematically maintained an elliptical PS during circumvention, but they adjusted its size according to different environmental factors. There was a relationship between the size of PS and level of attention, which suggests that the regulation of PS is used to control locomotion. This novel paradigm has important implications for the assessment and training of locomotor ability within real world environments.

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Stefan Kesenne

This article uses economic theory to examine the variables that affect the competitive balance in a professional sports league and the impact of revenue sharing. The generally accepted proposition that revenue sharing does not affect the competitive balance in a profi t-maximizing league has been challenged by many. It is shown that the competitive balance and the impact of revenue sharing not only depend on the relative size of the market of the clubs, but that they are also affected by the objectives of the club owners and the importance to spectators of absolute team quality and uncertainty of outcome. Furthermore, the clubs’ hiring strategies, including the talent supply conditions, turn out to be important elements affecting competitive balance and the impact of revenue sharing.

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Patricia Nascimento de Sousa, Marina Brito Silva, Andrea Cristina de Lima-Pardini and Luis Augusto Teixeira

The effect of resistance strength training on different phases of reactive postural responses to upright-stance perturbation was assessed in elderly women. Perturbation to body balance was produced by fast arm movements aiming at lifting different loads in either certain or uncertain contexts. Results from center-of-pressure analysis showed that lifting a light load under uncertainty led to more body sway than under certainty. Resistance strength training led to short periods of body sway in the compensation phase and to decreased variability in the stabilization phase of postural responses. These results suggest that neuromuscular adaptation from resistance strength training benefits late phases of postural responses to perturbation of body balance in the elderly.

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Richard J. Barker and Matthew R. Schofield

In a recent commentary on statistical inference, Batterham and Hopkins1 advocated an approach to statistical inference centered on expressions of uncertainty in parameters. After criticizing an approach to statistical inference driven by null hypothesis testing, they proposed a method of “magnitude-based” inference and then claimed that this approach is essentially Bayesian but with no prior assumption about the true value of the parameter. In this commentary, after we address the issues raised by Batterham and Hopkins, we show that their method is “approximately” Bayesian and rather than assuming no prior information their approach has a very specific, but hidden, joint prior on parameters. To correctly adopt the type of inference advocated by Batterham and Hopkins, sport scientists need to use fully Bayesian methods of analysis.

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Christoph Lienert, Claudine Sherrill and Bettye Myers

The purpose was to conduct a qualitative cross-cultural comparison of the concerns of physical educators in two countries about integration of children with and without disabilities. In-depth interviews were held with 30 regular elementary physical education teachers in Berlin (7 males, 9 females) and in the Dallas-Ft. Worth (DFW) area (2 males, 12 females), and observations were made of school settings. The Concerns-Based Adoption Model (CBAM) of Hall, Wallace, and Dossett (1973) guided the study. Data were analyzed by grounded theory procedures. Many concerns about integration were generalizable across cultures. In both countries, teachers reported concerns at only four of the seven stages of CBAM: personal, management, consequence, and collaboration. Most concerns focused on management. The major cultural difference was that DFW teachers reported more personal concerns (uncertainty about everyday demands and competence to meet these demands) than Berlin teachers. A dynamic systems model was proposed to guide future research.

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Calum Mattocks, Andy Ness, Sam Leary, Kate Tilling, Steven N. Blair, Julian Shield, Kevin Deere, Joanne Saunders, Joanne Kirkby, George Davey Smith, Jonathan Wells, Nicholas Wareham, John Reilly and Chris Riddoch

Background:

Objective methods can improve accuracy of physical activity measurement in field studies but uncertainties remain about their use.

Methods:

Children age 11 years from the Avon Longitudinal Study of Parents and Children (ALSPAC), were asked to wear a uni-axial accelerometer (MTI Actigraph) for 7 days.

Results:

Of 7159 children who attended for assessment, 5595 (78%) provided valid measures. The reliability coefficient for 3 days of recording was .7 and the power to detect a difference of 0.07 SDs (P ≤ .05) was > 90%. Measures tended to be higher on the first day of recording (17 counts/min; 95% CI, 10–24) and if children wore the monitor for fewer days, but these differences were small. The children who provided valid measures of activity were different from those who did not, but the differences were modest.

Conclusion:

Objective measures of physical activity can be incorporated into large longitudinal studies of children.

Open access

Darren J. Burgess

Research describing load-monitoring techniques for team sport is plentiful. Much of this research is conducted retrospectively and typically involves recreational or semielite teams. Load-monitoring research conducted on professional team sports is largely observational. Challenges exist for the practitioner in implementing peer-reviewed research into the applied setting. These challenges include match scheduling, player adherence, manager/coach buy-in, sport traditions, and staff availability. External-load monitoring often attracts questions surrounding technology reliability and validity, while internal-load monitoring makes some assumptions about player adherence, as well as having some uncertainty around the impact these measures have on player performance This commentary outlines examples of load-monitoring research, discusses the issues associated with the application of this research in an elite team-sport setting, and suggests practical adjustments to the existing research where necessary.

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Luis Augusto Teixeira, Mariana Marília Franzoni and Juliana Bayeux da Silva

Movement reprogramming in a task requiring timing accuracy was investigated in young and elderly individuals. The task consisted of manually hitting a hemiball in synchrony with the arrival of a moving light stimulus running through an electronic trackway. Movement reprogramming was required by unexpectedly changing the regular stimulus velocity at different moments before the due time of arrival at the interception position. Such changes produced times after velocity decrease (TAVD) between 150 ms and 750 ms, representing the periods of time available for generation of new movement timing specifications. Effect of probability of stimulus velocity change was investigated by comparing the conditions of 25% and 50% of chance of velocity decrease. Analysis of performance in conditions of velocity decrease showed an enlargement of temporal error as a function of longer TAVDs up to 300-375 ms. In conditions in which TAVDs were longer than 375 ms young participants showed a progressive improvement of accuracy over time, while the elderly were unable to improve their performance even for a TAVD of 750 ms. A trend toward a more efficient reprogramming with reduced uncertainty was observed only in the young. These results indicate that movement reprogramming is a continuous process in young individuals, but it is impaired in the elderly, preventing an appropriate reorganization of the action.