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41.
There is a paucity of research on devices suitable for home-based isometric exercise. Our aim was to compare cardiovascular responses to isometric exercise using novel and established methods. Ten individuals (age 34.0?±?8.5 years, mass 68.2?±?10.4?kg, height 1.72?±?0.09?m; mean?±?s) performed three different isometric exercise protocols with 48?h between each. Each protocol involved four repeated exercise bouts of 2?min at 30% maximum voluntary contraction force using alternate legs (transducer), alternate arms (transducer), or alternate arms (novel device). Systolic blood pressure, diastolic blood pressure, mean arterial blood pressure and heart rate were measured every 30?s. The highest (peak) values during each 2?min bout of exercise were recorded (peak systolic blood pressure, peak diastolic blood pressure, peak mean arterial blood pressure and peak heart rate). At the end of each 2?min exercise bout, the participants rated their perceived discomfort using Borg's CR-10 scale. There was a statistically significant difference in peak systolic blood pressure between isometric arm flexion using the force transducer and the novel device [158.1?±?10.8 vs. 149.1?±?13.9?mmHg (mean?±?s); P = 0.02]. Further analysis showed that peak systolic blood pressure was on average 9?mmHg higher using the force transducer with limits of agreement of –?15.97 to 33.97?mmHg. Analysis of the peak diastolic blood pressure, peak mean arterial blood pressure, peak heart rate and CR-10 data revealed no statistically significant differences between the three protocols. These results suggest that this novel, home-based method elicited similar cardiovascular responses during isometric exercise to those of established laboratory-based methods. However, the lower peak systolic blood pressure using the modified scales warrants further investigation before this method is used widely in the home.  相似文献   
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There is little published data in relation to the effects of caffeine upon cycling performance, speed and power in trained cyclists, especially during cycling of approximately 60 s duration. To address this, eight trained cyclists performed a 1 km time-trial on an electronically braked cycle ergometer under three conditions: after ingestion of 5 mg x kg-1 caffeine, after ingestion of a placebo, or a control condition. The three time-trials were performed in a randomized order and performance time, mean speed, mean power and peak power were determined. Caffeine ingestion resulted in improved performance time (caffeine vs. placebo vs. control: 71.1 +/- 2.0 vs. 73.4 +/- 2.3 vs. 73.3 +/- 2.7 s; P = 0.02; mean +/- s). This change represented a 3.1% (95% confidence interval: 0.7-5.6) improvement compared with the placebo condition. Mean speed was also higher in the caffeine than placebo and control conditions (caffeine vs. placebo vs. control: 50.7 +/- 1.4 vs. 49.1 +/- 1.5 vs. 49.2 +/- 1.7 km x h-1; P = 0.0005). Mean power increased after caffeine ingestion (caffeine vs. placebo vs. control: 523 +/- 43 vs. 505 +/- 46 vs. 504 +/- 38 W; P = 0.007). Peak power also increased from 864 +/- 107 W (placebo) and 830 +/- 87 W (control) to 940 +/- 83 W after caffeine ingestion (P = 0.027). These results provide support for previous research that found improved performance after caffeine ingestion during short-duration high-intensity exercise. The magnitude of the improvements observed in our study could be due to our use of sport-specific ergometry, a tablet form and trained participants.  相似文献   
43.
The analysis of variability both within and between performers can reveal important information about how athletes satisfy situational constraints. Transitory changes in the basketball free-throw shot were examined across different stages in skill development. Six female basketball players were selected, representing a range of playing expertise (pretest: 0-90% baskets scored). Each participant was video recorded performing 30 shots. Contrary to predictions, there was not a clear pattern of a reduction in trajectory variability with increasing skill level. However, improvements in skill level were associated with an increasing amount of intertrial movement consistency from the elbow and wrist joints. It is suggested that the angular motions of the elbow and wrist joints were compensated for each other toward the end of each throw to adapt to subtle changes in release parameters of the ball.  相似文献   
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In primary care specialties, Morning Report is a traditional vehicle for expanding medical residents' training in diagnosis and treatment. At one academic medical center, residents and faculty in the Department of Family and Community Medicine use case-based teaching, centered around planning and reviewing patient management, to review intriguing cases from patient encounters in the department's hospital service. Seeking to improve the level of evidence-based information exchanged at Morning Report, department leaders invited reference librarians from the health sciences library to attend weekly Morning Report. The librarians saw this as an opportunity not only to improve residents' information-seeking skills, but also to improve librarians' teaching skills and understanding of the needs of users in clinical settings. This paper describes the evolution of librarians' involvement in Morning Report, examples of the kinds of contributions librarians have made in this setting, and changes made in Morning Report sessions to facilitate this activity.  相似文献   
45.
This paper investigates how a sample of female Singaporean secondary school principals perceived their leadership styles and compares their responses to a similar study carried out recently of female English head teachers. The education systems of England and Singapore are quite different. The English environment allows schools significant autonomy in personnel management and the majority of head teachers and senior managers are male. In contrast, the Singaporean educational environment is quite centralized, including the management of career paths, and the proportion of female senior managers is much higher. Interviews were conducted with 11 female Singaporean principals to identify their styles of management, leadership perspectives, and attitudes. The discussion first focuses on whether or not the styles of the principals in relation to ‘masculine’ or feminine’ stereotypes of leadership were similar to those of the English head teachers. Further comparison is made of the leadership attributes of the two sets of principals, including styles of management, decision‐making, working environment, need for vision, and values.  相似文献   
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This study focuses on the experience of designing and implementing an action research-based curriculum in a secondary science classroom. By systematically examining ourselves and our practices, we brought to light beliefs and values that were realized through this process, came to a deeper understanding of our own learning, and developed new awareness as teachers and researchers. Here, we provide our perspective on how the process of curriculum design and implementation facilitated our personal and professional growth, and we share this as an example of how teacher educators and kindergarten through grade 12 teachers can position one another as generators and disseminators of knowledge through collaborative self-study to inform their own and others' teaching practices.  相似文献   
49.
The potential impact of increased physical activity on early literacy skills in preschool children has not been sufficiently explored. Therefore, the purpose of this study was to determine the effects of a 6 month, low cost, teacher-directed, academic program that delivered existing literacy lessons using physical activity in Head Start preschools. Preschool Literacy Individual Growth and Development Indicators were used to assess early literacy and phonological awareness in the areas of alliteration and picture naming. The results showed significant increases in physical activity during free play and improvements in early literacy (Picture Naming, Alliteration) compared to a non-exercising control group. In conclusion, the findings suggest that academic lessons taught using physical activity improve early literacy in preschoolers.  相似文献   
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