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Heidi L. Keller, Stephen E. Tolly and Patty S. Freedson

The sport of wrestling often encourages participants to engage in extreme weight loss practices in order to compete in a weight class one to three weight categories below normal weight. This review discusses the prevalence of the problem, methods wrestlers use to accomplish weight loss, and the health and performance consequences of rapid weight loss, with particular emphasis on weight cycling and minimal safe wrestling weight assessment. Some useful and practical recommendations for minimizing extreme weight loss practices are presented. Several state wrestling associations have adjusted their rules and regulations based on recommendations by organizations such as the American College of Sports Medicine to reduce the prevalence of the problem. Nevertheless, extreme weight loss continues to be a concern among health professionals, particularly with regard to health and performance.

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Iina Antikainen and Rebecca Ellis

Although physical activity interventions have been shown to effectively modify behavior, little research has examined the potential of these interventions for adoption in real-world settings. The purpose of this literature review was to evaluate the external validity of 57 theory-based physical activity interventions using the RE-AIM framework. The physical activity interventions included were more likely to report on issues of internal, rather than external validity and on individual, rather than organizational components of the RE-AIM framework, making the translation of many interventions into practice difficult. Furthermore, most studies included motivated, healthy participants, thus reducing the generalizability of the interventions to real-world settings that provide services to more diverse populations. To determine if a given intervention is feasible and effective in translational research, more information should be reported about the factors that affect external validity.

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Daniela Mattos, Joshua Kuhl, John P. Scholz and Mark L. Latash

The concept of motor equivalent combinations of arm muscles, or M-modes, was investigated during reaching to insert a pointer into a cylindrical target with and without an elbow perturbation. Five M-modes across 15 arm/scapula muscles were identified by principal component analysis with factor extraction. The relationship between small changes in the M-modes and changes in the position/orientation of the pointer were investigated by linear regression analyses. The results revealed a motor equivalent organization of the M-modes for perturbed compared with nonperturbed reaches, both with respect to hand position and orientation, especially in the first 100-ms postperturbation. Similar findings were obtained for motor equivalence computed based on changes in the joint configuration, although the kinematically defined motor equivalence was stronger for pointer orientation. The results support the hypothesis that the nervous system organizes muscles into M-modes and flexibly scales M-mode activation to preserve stable values of variables directly related to performance success.

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David Cardenas, Karla A. Henderson and Beth E. Wilson

The purpose of the article was to examine the physical activity perceptions and behaviors of older adults who were active participants in a statewide senior games (i.e., North Carolina Senior Games; NCSG) program with its focus on year-round involvement through activities in local communities. A random sample of 440 older adults (55 years and older) completed a questionnaire in 2006 about their participation in community-based senior games. A uniqueness of this study is its focus on active older adults, which provides insight into how to maintain physical involvement. Older adults who were most active perceived the most benefits from senior games but did not necessarily have the fewest constraints. This study of NCSG as an organization designed to promote healthy living in communities offered an example of how a social-ecological framework aimed at health promotion can be applied.

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Melvin H. Williams

As nutritional technology advanced, scientists have been able to synthesize and manufacture all known nutrients, and many of their metabolic by-products, essential to human physiology. Many of these substances are theorized to possess ergogenic potential when take in quantities or forms normally not found in typical foods or diets. Research, although limited in most cases, supports the ergogenicity of some nutrients (e.g., creatine) when consumed in substantial amounts, suggesting such nutrients may function as drugs or nutraceuticals. The International Olympic Committee (IOC) doping legislation stipulates that any physiologic substance taken in abnormal quantity with the intention of artificially and unfairly increasing performance should be construed as doping, violating the ethics of sport performance. Given this stipulation, the IOC and other athletic-governing organizations should consider the legality and ethics underlying the use of ergogenic nutraceuticals in sport.

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Marjorie H. Woollacott and Anne Shumway-Cook

Current research suggests that there are complex interactions between intrinsic factors related to the individual and extrinsic environmental factors, all of which contribute to falls in the older adult. A new approach to balance assessment, the task-oriented conceptual framework for clinical intervention, takes into account many of these intrinsic and extrinsic variables in assessing balance function. It contains three levels of assessment of balance and gait function: performance-based functional assessment, strategy assessment, and impairment assessment. This approach quantifies performance on functional tests of balance, determines the strategies used by the individual to carry out functional tasks, and evaluates the relative contribution of specific neural and musculoskeletal variables to normal postural control. Results of recent experiments suggest that older adults who are given a sensory training program that is designed to improve the organization of sensory inputs contributing to balance control (strategy level) are able to significantly improve sway and that this training effect transfers to other balance conditions.

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Christopher M. Janelle, Charles H. Hillman, Ross J. Apparies, Nicholas P. Murray, Launi Meili, Elizabeth A. Fallon and Bradley D. Hatfield

The purpose of this study was to examine whether variability in gaze behavior and cortical activation would differentiate expert (n = 12) and nonexpert (n = 13) small-bore rifle shooters. Spectral-activity and eye-movement data were collected concurrently during the course of a regulation indoor sequence of 40 shots from the standing position. Experts exhibited significantly superior shooting performance, as well as a significantly longer quiet eye period preceding shot execution than did nonexperts. Additionally, expertise interacted with hemispheric activation levels: Experts demonstrated a significant increase in left-hemisphere alpha and beta power, accompanied by a reduction in right-hemisphere alpha and beta power, during the preparatory period just prior to the shot. Nonexperts exhibited similar hemispheric asymmetry, but to a lesser extent than did experts. Findings suggest systematic expertise-related differences in ocular and cortical activity during the preparatory phase leading up to the trigger pull that reflects more optimal organization of the neural structures needed to achieve high-level performance.

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Jean Côté, John Saimela, Pierre Trudel, Abderrahim Baria and Storm Russell

An expert system approach (Buchanan et al., 1983) was used to identify and conceptualize the knowledge of 17 Canadian expert high-performance gymnastic coaches. The knowledge elicitation process consisted of open-ended questions and various questioning methods to unveil, explore, and prove important information (Patton, 1987; Spradley, 1979) about coaching. All coaches’ interviews were transcribed verbatim, and the unstructured qualitative data were inductively analyzed following the procedures and techniques of grounded theory (Strauss & Corbin, 1990). The inductive analysis process allowed the meaning units of the interview transcripts to be regrouped into properties, categories, and components. The components emerging from the analysis consisted of (a) competition, (b) training, (c) organization, (d) coach’s personal characteristics, (e) gymnast’s personal characteristics and level of development, and (f) contextual factors. These components were further developed into a model representing coaches’ knowledge.

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Nikos Ntoumanis, Anne-Marte Pensgaard, Chris Martin and Katie Pipe

The purpose of this study was to provide an in-depth account of amotivation in compulsory school physical education by examining its major causes, the way it is displayed, and how it can be tackled. From an initial participant pool of 390 British schoolchildren ages 14 to 15 years, 21 of them (15 girls and 6 boys) were selected to participate in semi-structured interviews. They were categorized as being amotivated based on their responses to a questionnaire measuring motivation in physical education. Three main perceived causes of amotivation were identified in the interviews: learned helplessness beliefs, low need satisfaction, and contextual factors. Amotivation was mainly displayed by nonattendance, low involvement in the class, and low intention to be physically active after leaving school. Students’ suggestions for reducing amotivation focused on the enhancement of positive affect, need satisfaction, and structural/organizational changes. The findings are discussed in conjunction with contemporary motivation theories and models of amotivation.

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Kathleen Benjamin, Nancy Edwards and Wenda Caswell

In 2006, the authors conducted a multisite qualitative study in Ottawa, Ontario, Canada to examine organizational and environmental factors that influence physical activity for long-term-care (LTC) residents. The article describes the results of interviews with 9 administrators from nonprofit and for-profit LTC facilities. A content analysis revealed that despite having positive views about the value of physical activity, the administrators encountered challenges related to funding, human resources, and the built (physical) environment. The intersection of staffing issues and challenges in the built environment created less than optimal conditions for physical activity programs. Findings suggest that until there are adequate human and financial resources, it will be difficult to implement evidence-informed physical activity programs for residents in LTC settings in Ontario. A review of provincial LTC standards for physical activity program requirements and the built environment is warranted.