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131.
Women are more prone to anterior cruciate ligament (ACL) injury during cutting sports than men. The purpose of this study was to examine knee kinematic and ground reaction forces (GRF) differences between genders during cutting. Male and female athletes performed cutting trials while force platform and video data were recorded (180 Hz). Differences (p < . 05) were observed between groups for knee flexion at contact and GRF at maximum knee flexion. Women averaged 5.8 degrees less flexion at contact and 1.0 N. (kg x m x s(-1))(-1) greater GRF at maximum flexion. Knee range of motion and peak GRF variables were not significantly different, but women had greater values. Women exhibited technique characteristics believed to increase ACL injury risk, but men exhibiting similar characteristics were also observed and could also be at risk.  相似文献   
132.
Abstract

The aim of this study was to compare optimization and correction procedures for the determination of peak power output during friction-loaded cycle ergometry. Ten male and 10 female sports students each performed five 10-s sprints from a stationary start on a Monark 864 basket-loaded ergometer. Resistive loads of 5.0, 6.5, 8.0, 9.5, and 11.0% body weight were administered in a counterbalanced order, with a recovery period of 10 min between sprints. Peak power was greater and occurred earlier, with less work having been done before the attainment of peak power, when the data were corrected to account for the inertial and frictional characteristics of the ergometer. Corrected peak power was independent of resistive load (P > 0.05), whereas uncorrected peak power varied as a quadratic function of load (P < 0.001). For males and females, optimized peak power (971 ± 122 and 668 ± 37 W) was lower (P < 0.01) than either the highest (1074 ± 111 and 754 ± 56 W respectively) or the mean (1007 ± 125 and 701 ± 45 W respectively) of the five values for corrected peak power. Optimized and mean corrected peak power were highly correlated both in males (r = 0.97, P < 0.001) and females (r = 0.96, P < 0.001). The difference between optimized and mean corrected peak power was 37 ± 30 W in males and 33 ± 14 W in females, of which approximately 15 W was due to the correction for frictional losses. We conclude that corrected peak power is independent of resistive load in males and females.  相似文献   
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Abstract

Inertial sensors may provide the opportunity for broader and more cost effective gait analysis; however some questions remain over their potential use in this capacity. The aim of the study was to determine whether an inertial sensor could discriminate between normal walking, fast walking, and running. A single group crossover design was used to compare acceleration profiles between three gait conditions: normal walking, fast walking, and running. An inertial sensor was placed on the sacrum of 12 participants (6 male, 6 female) who performed 3 trials of each gait condition on both overground and treadmill settings. A significant difference (P < 0.001) in the occurrence of heel strike in the gait cycle was found between running and both walking conditions. No differences were seen between overground and treadmill in any condition or variable. The results indicate that a single sacral mounted inertial sensor can differentiate running from normal walking and fast walking using temporal gait event measures. This study indicates that inertial sensors can differentiate walking from running gait in healthy individuals which may have potential for application in the quantification of physical activity in the health and exercise industry.  相似文献   
135.
Abstract

Two groups of 23 junior high school boys were tested before and after an eight weeks' progressive resistance training program. The experimental group participated in this program, but the control group took part only in regularly scheduled physical education classes. At the end of the eight weeks, it was found that the experimental group increased their ability to do pull-ups, push-ups, the Harvard Step Test, Dodge run, the Burpee test, and trunk extension and flexion. The control group improved in the Dodge run, the Burpee test, push-ups, and trunk extension. In no case did the improvement of the control group exceed the improvement of the experimental group. The experimental group also increased in anthropometric measurements. Medical examinations indicated that no harmful effects were experienced by either group.  相似文献   
136.
Standards-based assessment rubrics are recognised as an important tool for ensuring clear criteria in higher education. Most of the available evidence on rubrics comes from studies with face-to-face undergraduate students. Our study evaluated the introduction of rubrics into a postgraduate subject that included both online and face-to-face students. We conducted formative evaluation with former students to develop the rubrics, as well as surveying current students for process and impact evaluation, supplemented with a focus group. Process results showed that the rubrics were used widely and were generally considered to be of at least some use. Clarity of the rubrics was the main issue affecting perceived usefulness, particularly for the assessment tasks that had undergone comparatively less formative evaluation. Impact evaluation showed mixed results, with students that reported always using rubrics having higher marks on average compared to students who did not always use the rubrics. However, an expected improvement in marks across the whole student cohort compared to previous years did not eventuate, although this could be explained by a number of factors independent of the rubrics. Our results provide some evidence for the use of rubrics in postgraduate and online settings but highlight the need for rigorous formative evaluation.  相似文献   
137.
The involvement of working memory capacity (WMC) in ruled-based cognitive skill acquisition is well-established, but the duration of its involvement and its role in learning strategy selection are less certain. Participants (N = 610) learned four logic rules, their corresponding symbols, or logic gates, and the appropriate input–output combinations in three-gate circuit patterns. Participants practiced 120 repetitions of each rule (480 total gates) over the course of 10 training blocks. Memory load varied between subjects. The confluence of task demands and individual differences in WMC (N = 518) dramatically affected speed–accuracy tradeoffs and strategic use of a computerized help function. Cluster analysis revealed five distinct groups of participants based on the combination of response accuracy, latency, and help use. Some groups with moderate to high mean WMC acquired the task with predictable performance patterns. Other groups, prevalently under a memory load and with low mean WMC, failed to learn or overused help.  相似文献   
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The first year of a 5 year professional development project for elementary teachers in two mid-western states integrated a bridge of two distinctly different distance education networks (T-1 and fiber optics) to provide science professional development for elementary school teachers in rural communities. Interactive television (ITV), the title given to the distance component, consisted of a series of twenty-four, 2 h presentations by scientists and content specialists. It provided expansion to the science pedagogical content knowledge of the elementary teachers involved. Eighty-five teachers in 38 school districts from the two states completed individual surveys following the final ITV session. Analysis of variance of participants post-session survey scores yielded differences (p < 0.05) on the subscales measuring perceived effectiveness of using distance education for professional development purposes and years of teaching experience. Teachers with over 20 years of classroom experience perceived the use of distance education technologies for science professional development to be more effective than teachers with 16–20 years of classroom experience. These results might suggest another digital divide.  相似文献   
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