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11.
In February of 2011, an earthquake destroyed the only all-weather athletics facility in the city of Christchurch, New Zealand. The all-weather track has yet to be replaced, and so since the loss of the track, local Christchurch athletes have only had a grass track for training and preparation for championship events. The present study considers what effect the loss of the training facility has had on the performance of athletes from Christchurch at national championship events. Not surprisingly, the study finds that there has been a deterioration in the performance in events that are heavily dependent upon the all-weather surface. However, somewhat more surprisingly, the loss of the track appears to have caused a significant improvement in the performance of Christchurch athletes in events that, while on the standard athletics programme, are not heavily dependent on track surface.  相似文献   
12.
The aim of this study was to compare sprint performance over 10 and 20?m when participants ran while towing resistances, weighing between 0 and 30% of body mass. The sample of 33 participants consisted of male rugby and soccer players (age 21.1?±?1.8 years, body mass 83.6?±?13.1?kg, height 1.82?±?0.1?m; mean?±?s). Each participant performed two sets of seven sprints over 20?m using a Latin rectangular design. The times were recorded at 10 and 20?m using electronic speed gates. The sprints of 13 players were video-recorded to allow calculation of stride length and frequency. For both sprints, a quadratic relationship was observed between sprint time and resistance as sprint time increased from 2.94?s to 3.80?s from 0 to 30% resistance. This relationship was statistically significant but considered not to be meaningful for performance because, over the range of resistances used in this study, the quadratic model was never more than 1% (in terms of sprint time) from the linear model. As resistance increased, the stride length shortened, with mean values of 1.63?±?0.13?m at 0% body mass and 1.33?±?0.13?m at 30% of body mass. There was no significant change in stride frequency with increasing resistance. The results show that in general there is an increase in sprint time with an increase in resistance. No particular resistance in the range tested (0?–?30%) can be recommended for practice.  相似文献   
13.
This mixed-methods research study offers insights and explanations into gender imbalance in the college readiness program, Advancement Via Individual Determination (AVID). Over 200 schools that have been implementing AVID for more than 4 years across the United States participated in this study. Three years of archived historical data pertaining to school demographic information and AVID certification information was accessed and analyzed to examine recruitment and retention of male and female students over time, as well as student enrollment in rigorous curriculum. Our research indicated that at the high school level, gender disparity became most apparent in the 11th and 12th grades. Results indicated that schools that struggled to recruit and retain boys continued to enroll AVID students, both boys and girls, into rigorous advanced placement curriculum at comparable rates as schools that did not struggle to recruit and retain boys in the program. This indicates that once in AVID, boys and girls are provided equal access to rigor; however, recruiting and retaining boys in AVID continues to be a challenge for AVID schools. Research participants indicated that academic identity, peer and family support, leadership and mentoring opportunities and male role models influence male participation in AVID.  相似文献   
14.
Changes in student self- and task evaluations, subjective valuation, and achievement behavior in mathematics and English over the 1st year of junior high form the basis of this study. The transition to junior high has been found to negatively affect students' self-concept and subjective valuation in mathematics and English, but previous research has not addressed changes in task evaluations and achievement behaviors. Gender and level of academic achievement effects are also relevant to the nature of changes in student attitudes. The participants (N =400) were from 3 coeducational Australian government schools in metropolitan Sydney of comparable socioeconomic status. When changes in perceptions occurred, they were negative, and gender differences favored boys in mathematics and girls in English. However, the nature and extent of change was dependent on school and level of achievement.  相似文献   
15.
The capacity to achieve and retain control over one's own life—to make decisions about and exert power over one's situation—is strongly correlated with being healthy. For older persons, there is a real danger that professionals with good intentions will encroach on this control in the name of providing service. We examine the issues of power, control, decision making, and healthy aging from the perspective of educating health care providers. Particular attention is paid to how health care providers see their role in defining older adults as being at risk when they refuse service or take risks that providers define as unacceptable. We raise this issue of appropriate professional control and cite the literature on successful coping to argue for policies and practices that enhance personal autonomy and interdependence as effective vehicles for healthy aging. Lessons from primary health care are applied to healthy aging even in the face of diminished capacities.  相似文献   
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17.
The resistance against a cyclist while riding on rollers is due mainly to rolling resistance produced by the deformation of the tyre as it rolls against small diameter drums. Resistance is then combined with wheel speed to set power output. The effect of tyre pressure and cross-section on power was investigated by systematically altering the pressure (552 kPa, 690 kPa, and 827 KPa) in a 20c, 23c, 25c, and 28c tyre of the same design while riding at a wheel speed of 45 kph. Average power over 1 minute was measured with a Power Tap Hub (Tune Corporation, Cambridge, Massachusetts, USA) on five occasions. Statistical significance was evaluated at p < 0.05. Power requirements increased significantly with each reduction in tyre pressure for all tyres and pressures except the 25c between 690 and 827 kPa. The 20c tyre required significantly more power from the cyclist at each tested tyre pressure when compared to the other tyres (which were not different from each other). The differences in resistance from tyre size were not observed when ridden on the road. Additionally, a slightly different tyre design from the same manufacturer responded similarly in the 20c, but was significantly different in the 23c size. It was also observed that power requirements increased significantly when both the wheels were ridden on the rollers as compared to just the rear wheel. These results indicate that the power requirements may be significantly altered by the cyclist by adjusting tyre pressure, tyre cross-section size, tyre type, and with the number of wheels contacting the rollers. However, the magnitude of these power requirements may not be suitable for intense workouts of trained cyclists.  相似文献   
18.
The aim of the study was to examine several physiological responses to a climbing-specific task to identify determinants of endurance in sport rock climbing. Finger strength and endurance of intermediate rock climbers (n = 11) and non-climbers (n = 9) were compared using climbing-specific apparatus. After maximum voluntary contraction (MVC) trials, two isometric endurance tests were performed at 40% (s = 2.5%) MVC until volitional exhaustion (continuous contractions and intermittent contractions of 10 s, with 3 s rest between contractions). Changes in muscle blood oxygenation and muscle blood volume were recorded in the flexor digitorum superficialis using near infra-red spectroscopy. Statistical significance was set at P < 0.05. Climbers had a higher mean MVC (climbers: 485 N, s = 65; non-climbers 375 N, s = 91) (P = 0.009). The group mean endurance test times were similar. The force-time integral, used as a measure of climbing-specific endurance, was greater for climbers in the intermittent test (climbers: 51,769 N x s, s = 12,229; non-climbers: 35,325 N x s, s = 9724) but not in the continuous test (climbers: 21,043 N x s, s = 4474; non-climbers: 15,816 N x s, s = 6263). Recovery of forearm oxygenation during rest phases (intermittent test) explained 41.1% of the variability in the force-time integral. Change in total haemoglobin was significantly greater in non-climbers (continuous test) than climbers (P = 0.023--40% test timepoint, P = 0.014--60% test timepoint). Pressor responses were similar between groups and not related to the force-time integral for either test. We conclude that muscle re-oxygenation during rest phases is a predictor of endurance performance.  相似文献   
19.
The aim of this study was to determine the effect of 10 days of heat acclimation with and without pre-cooling on intermittent sprint exercise performance in the heat. Eight males completed three intermittent cycling sprint protocols before and after 10 days of heat acclimation. Before acclimation, one sprint protocol was conducted in control conditions (21.8 ± 2.2°C, 42.8 ± 6.7% relative humidity) and two sprint protocols in hot, humid conditions (33.3 ± 0.6°C, 52.2 ± 6.8% relative humidity) in a randomized order. One hot, humid condition was preceded by 20 min of thigh pre-cooling with ice packs (-16.2 ± 4.5°C). After heat acclimation, the two hot, humid sprint protocols were repeated. Before heat acclimation, peak power output declined in the heat (P < 0.05) but pre-cooling prevented this. Ten days of heat acclimation reduced resting rectal temperature from 37.8 ± 0.3°C to 37.4 ± 0.3°C (P < 0.01). When acclimated, peak power output increased by ~2% (P < 0.05, main effect) and no reductions in individual sprint peak power output were observed. Additional pre-cooling offered no further ergogenic effect. Unacclimated athletes competing in the heat should pre-cool to prevent reductions in peak power output, but heat acclimate for an increased peak power output.  相似文献   
20.
This article examines the efficacy of policy and practice, within one Scottish region, of education about sexuality in secondary schools. The primary focus is on teaching sexuality to pupils with recorded learning difficulties, with a particular emphasis on the concepts of inclusion, normalisation and integration. The authors are Sheila Watt, Lecturer in the School of Education, University of Dundee; Elizabeth Horn, a teacher of pupils with special educational needs; and Cassie Higgins, a research assistant also based in the School of Education at the University of Dundee.  相似文献   
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