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971.
John D. Van Buren 《Journal of The Franklin Institute》1866,81(4):219-223
972.
Michael J Shoemaker Heather Hurt Leah Arndt 《Cardiopulmonary Physical Therapy Journal》2008,19(3):75-83
Purpose: To conduct a systematic review of the evidence regarding the efficacy of exercise training in the management of cystic fibrosis (CF).Methods: Articles were found by searching PEDRO, MEDLINE, and CINAHL databases. Included articles involved exercise-related interventions for long-term adaptations (ie, not acute effects of exercise). Articles were excluded if the language was other than English or if other non-exercise interventions were used. Date of publication was not a factor for exclusion. Two independent reviewers evaluated the included articles using Sackett''s levels of evidence and select scoring criteria.Results: Twelve articles were eligible for inclusion. Interventions studied included various aspects of exercise training: anaerobic, aerobic, or resistance training. Study end-points included pulmonary function, aerobic capacity, strength, and health-related quality of life (HRQL).Conclusions: Exercise training in individuals with CF is beneficial, with aerobic and resistance training having the greatest support in the literature for improved aerobic capacity and strength, respectively. Exercise training does not appear to have an effect of improving pulmonary function, but may have a preservation effect. Strong conclusions about improvement in HQRL from exercise training cannot be made. However, greater consistency in measuring this outcome is needed in future trials. There is a paucity of evidence regarding the role of exercise training in reducing hospitalization and health care utilization, and questions raised by this review should be considered in the design of future trials.Key Words: cystic fibrosis, aerobic exercise, review 相似文献
973.
Since the time of state socialism, Hungarian sport has been totally financed by the state. Therefore, Hungarian soccer and sponsorship market is a relatively new and unexplored subject of research in the field of sports sponsorship, as most studies so far have focused on the major European soccer leagues. The main objective of this paper, focusing on the Hungarian soccer sponsorship market, was to evaluate the range of soccer sponsorship objectives and the range of evaluation tools that sponsors use to measure the effectiveness of their sponsorships. A combined approach of qualitative and quantitative research methods served as the methodological foundation of this study. In the quantitative phase, representatives of the sponsor companies (n=103) were asked to rate the importance of the sponsorship objectives and the importance of the evaluation techniques used to measure the effectiveness of their sponsorships. The results of this study have implications for the sports sponsorship industry, the Hungarian soccer club sponsors, and the sport properties too. According to the research results, many of the Hungarian sponsor companies have failed to assess the effectiveness of sponsorship in meeting their objectives. The research can be used to bridge the gap between the theory and practice of soccer sponsorship in Hungary. 相似文献
974.
Understanding the role of shaft stiffness in the golf swing 总被引:3,自引:3,他引:0
Theoretically, shaft stiffness can alter shot distance by increasing clubhead speed or altering clubhead orientation at impact.
A 3D forward dynamics model of a golfer and flexible club simulated the downswing. A genetic algorithm optimized the coordination
of the model’s muscles (four torque generators) to maximize clubhead speed. The maximum torque output and maximum rate of
torque development from the torque generators were varied to simulate the swing of golfers that generate different clubhead
speeds. Four shafts of varying stiffness (flexible, regular, stiff, and completely rigid) were entered into these simulations
to examine the role that shaft flexibility had on clubhead speed and orientation at impact. Shaft stiffness was found to have
a meaningful effect only on clubhead orientation (dynamic loft and dynamic close) at impact. There was no evidence to support
the premise that matching the stiffness properties of the shaft with the golfer would improve clubhead speed. 相似文献
975.
976.
Tyler J. Stidwill Rene Albert Turcotte Phil Dixon David J. Pearsall 《Sports Engineering》2009,12(2):63-68
The purpose of this study was to develop a portable force measurement system for ice hockey skating. The system consisted
of three strain gauge pairs affixed to an ice hockey skate’s blade holder with wire leads connected to a microprocessor controlled
data acquisition device carried in a backpack worn by the skater. The configuration of the strain gauges simultaneously determined
the vertical and medial–lateral force components experienced by the blade holder with a resolution accuracy of 1.9 N and a
coefficient of variation of 9.2%. On-ice testing of this system with subjects performing forward start, acceleration, and
constant velocity skating permitted unencumbered, natural movement and demonstrated clear, unambiguous signal responses, high
trial-to-trial repeatability, and easy data retrieval. The practicality and accuracy of this testing approach have many applications,
such as a quantitative tool for skating force assessment to aid athletes and coaches, as well as providing the means to examine
other skill-specific dynamics. 相似文献
977.
Acknowledgement
Acknowledgements 相似文献978.
Accurate measurement of physical activity is fundamentally important in epidemiological research of physical activity behavior A widely used telephone-based physical activity questionnaire was compared with other methods of administration and objective measures (pedometers and accelerometers) among 80 adults (43 women). The telephone questionnaire was comparable to both the self-administered form and international telephone-administered equivalent. Although moderate correlation coefficients with objective measures supported the use of the questionnaire, wide prediction intervals generated using Bland Altman methods highlighted large discrepancies between the measures, particularly in the moderate intensity category. These findings illustrate the limitations of correlation coefficients in validation studies and the inaccuracy of self-report questionnaires in measuring physical activity. 相似文献
979.
980.
A sport-specific measure of moral disengagement was developed in 2 studies. In Study 1, a 59-item questionnaire was developed and tested with 308 athletes from 5 team sports. A series of confirmatory factor analyses (CFA) testing different models suggested the model that best fitted the data had 6 first-order factors that could be represented by 1 second-order factor. Study 2 involved 305 athletes from the same 5 sports. CFA confirmed the 6-factor, second-order structure for the final 32-item measure. Results from Study 2 supported the construct validity of the scale, providing evidence for the factorial, concurrent, convergent, and discriminant validity. The Moral Disengagement in Sport Scale (MDSS) is proposed as a valid and reliable measure of moral disengagement for use in the sport context. 相似文献