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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
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We analyse the evolution of the slope (critical speed) and the y-intercept (anaerobic distance capacity) of the linear distance-time relationship over a century of Olympic running performances. The distance-time relationship of each Olympic Games (1920-2004) was plotted using the performances in the 800-, 1500- and 5000-m track events. Values for critical speed and anaerobic distance capacity were determined by linear modelling. Mean performances for the 800, 1500 and 5000 m were 104.9 +/- 1.5 s (1.4%), 217.2 +/- 2.8 s (1.3%) and 808.9 +/- 18.4 s (2.3%), respectively. Critical speed improved during the first three-quarters of the twentieth century to reach a plateau in 1984. This is in accordance with the literature (Peronnet & Thibault, 1989) and suggests that "human aerobic endurance" has improved within the century (+13.4%) and tends to stabilize. Anaerobic distance capacity was highly variable over the century (coefficient of variation = 9.4%) and did not show a linear improvement over the years as has previously been suggested (Peronnet & Thibault, 1989). This could be due to an artefact in the application of the two-parameter model to only three Olympic performances. A limitation to the use of this linear mathematical model to fit physiological data may have been demonstrated. 相似文献
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Lisa M. W. DaDeppo 《Learning disabilities research & practice》2009,24(3):122-131
Despite increased enrollment, outcomes such as grade point average (GPA), persistence, and graduation rates for college students with learning disabilities (LD) continue to lag behind those of their nondisabled peers. Reasons for the differences vary but may include academic and social integration, factors identified as important to the success of college students in general. This research investigated the relative influence of background characteristics, precollege achievement, and college integration variables on the academic success and intent to persist of college freshmen and sophomores with LD. While academic and social integration were not unique predictors of college GPA, both integration variables were unique predictors of intent to persist. The findings suggest that beyond high school achievement and background characteristics, college experiences as captured by academic and social integration are promising constructs to help explain the persistence of college students with LD. Implications for future research and practices for high school and college personnel are discussed. 相似文献
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