维吾尔族7—18岁城乡青少年身体形态比较

了解维吾尔族青少年身体形态状况、形态发育的变化特点及其变化规律,为改善维吾尔族青少年体质健康水平提供依据。采用专家访谈法、测试和数理统计法,于2012年10—12月,对新疆和田地区中小学7—18岁4800名维吾尔族青少年的身高、体重和胸围指标进行统计分析,并针对问题提出相关建议。     

A comparison of two methods for the calculation of accumulated oxygen deficit

Abstract

The aim of this study was to compare accumulated oxygen deficit data derived using two different exercise protocols with the aim of producing a less time-consuming test specifically for use with athletes. Six road and four track male endurance cyclists performed two series of cycle ergometer tests. The first series involved five 10 min sub-maximal cycle exercise bouts, a VO_2peak test and a 115% VO_2peak test. Data from these tests were used to estimate the accumulated oxygen deficit according to the calculations of Medbø et al. (1988). In the second series of tests, participants performed a 15 min incremental cycle ergometer test followed, 2 min later, by a 2 min variable resistance test in which they completed as much work as possible while pedalling at a constant rate. Analysis revealed that the accumulated oxygen deficit calculated from the first series of tests was higher (P<0.02) than that calculated from the second series: 52.3±11.7 and 43.9±6.4 ml·kg^?1, respectively (mean±s). Other significant differences between the two protocols were observed for VO_2peak, total work and maximal heart rate; all were higher during the modified protocol (P<0.01 and P<0.02, respectively). Oxygen kinetics were also significantly faster during the modified 2 min maximal test. We conclude that the difference in accumulated oxygen deficit between protocols was probably due to a reduced oxygen uptake, possibly caused by a slower oxygen on-response during the 115% VO_2peak test in the first series, and VO₂—power output regression differences caused by an elevated VO ₂ during the early stages of the second series.     

Athlete burnout in elite sport: A self-determination perspective

Abstract

The practice of exercise has shown to be beneficial to quality of life of individuals with HIV/AIDS. Thus, the present study analysed the effects of a combined exercise training in persons living with HIV/AIDS. Ten participants participated in the present study. The following variables were analysed: viral load and cell counts for TCD4+/TCD8; maximal oxygen consumption (VO_2max); total mass, absolute fat mass, relative fat mass, absolute lean mass, relative lean mass and body mass index; fasting glycaemia, fasting insulinaemia, homeostatic model assessment (HOMA) index (insulin resistance – homeostatic model assessment (IR-HOMA)); total cholesterol, triglycerides, high-density lipoprotein (HDL), very low-density lipoprotein (VLDL), low-density lipoprotein (LDL); superoxide dismutase, catalase, glutathione peroxidase activities; thiobarbituric acid reactive substances. The combined exercise training consisted of resistance exercises plus aerobic training (60 min · session^?1, three times per week, during 20 weeks). The number of TCD4+ cells, absolute lean mass and relative lean mass, muscle strength for the 45° leg press, seated row and triceps extension, HDL-c levels as well as VO_2max increased post-training. The activity of superoxide dismutase, catalase, glutathione peroxidase enzymes and thiobarbituric acid reactive substances levels were diminished post-training. Finally, it can be concluded that combined exercise training is able to change positively several variables related to health of individuals with HIV/AIDS, mainly the immune system as well as antioxidant mechanisms re-establishment.     

Effects of weighted sled towing on ground reaction force during the acceleration phase of sprint running

Abstract

Athletes use weighted sled towing to improve sprint ability, but little is known about its biomechanics. The purpose of this study was to investigate the effect of weighted sled towing with two different loads on ground reaction force. Ten physically active men (mean ± SD: age 27.9 ± 1.9 years; stature 1.76 ± 0.06 m; body mass 80.2 ± 9.6 kg) performed 5 m sprints under three conditions; (a) unresisted, (b) towing a sled weighing 10% of body mass (10% condition) and (c) towing a sled weighing 30% of body mass (30% condition). Ground reaction force data during the second ground contact after the start were recorded and compared across the three conditions. No significant differences between the unresisted and 10% conditions were evident, whereas the 30% condition resulted in significantly greater values for the net horizontal and propulsive impulses (P < 0.05) compared with the unresisted condition due to longer contact time and more horizontal direction of force application to the ground. It is concluded that towing a sled weighing 30% of body mass requires more horizontal force application and increases the demand for horizontal impulse production. In contrast, the use of 10% body mass has minimal impact on ground reaction force.     

UNIVERSITY STUDENTS’ VIEWS OF THE ROLE OF MATHEMATICS IN THEIR FUTURE

We report on an international study about mathematics students’ ideas of how they will use mathematics in their future study and careers. This builds on our previous research into students’ conceptions of mathematics. In this paper, we use data from two groups of students studying mathematics: those who participated in an in-depth interview and those who completed an open-ended questionnaire. We found that their responses could be grouped into four categories: don’t know; procedural skills; conceptual skills; and professional skills. Although some students held clear ideas about the role of mathematics, many were not able to articulate how it would be used in their future. This has implications for their approach to learning and our approach to teaching.     

Distributed leadership of school curriculum change: an integrative approach

Since its inception in 1999, the distributed leadership framework of Spillane, Halverson, and Diamond [2004. “Towards a Theory of Leadership Practice: A Distributed Perspective.” Journal of Curriculum Studies 36 (1): 3–34. doi:10.1080/0022027032000106726] has supported research into leadership and change in schools. Whilst the conceptual integrity of the framework is sound, research based upon its premises has attracted some criticism. The research has had a narrowed focus which has not generally reflected the inseparability of the elements of the framework and the situation within which leadership is enacted. In addition, it often fails to account for the complexity of critical elements of the environment such as micropolitics. This position paper proposes a reconfiguration of the distributed leadership framework as a research framework in response to this critique. The paper asserts that this new perspective that is presented is able to respond to the critique through an integrated approach that encompasses situation, social distribution and task enactment and which supports an integrated approach to research methodology. This adapted framework has the potential to more fully support research design that is actuality holistic and embedded in the context.     

Stuart Hall at the Open University

ABSTRACT

Accounts of the influence of Stuart Hall's thought on subsequent developments tend to neglect his work at the Open University. This unjustifiable neglect is illustrated by the example of his contribution to the course on Beliefs and Ideology, especially his article on 'Religious ideologies and social movements in Jamaica' [Hall, S. (1985). Religious ideologies and social movements in Jamaica. In R. Bocock & K. Thompson (Eds.), Religion and ideology (pp. 269–297). Manchester, UK: Manchester University Press].     

Students as epistemological agents: claiming life experience as real knowledge in health professional education

Higher Education - University teachers’ practices of resistance against dominant epistemological norms have been described in recent critical higher education literature, but comparatively...     

Higher Education and Fair Employment in Northern Ireland

As equal opportunities are assuming greater significance in higher education this paper examines the issue of fair employment in the two universities in Northern Ireland. The development of higher education and the evolution of fair employment policy which seeks to promote greater equality of opportunity in employment between Protestants and Catholics, are outlined. The employment practices and profiles of Northern Ireland's two universities are considered. Under the 1989 Fair Employment Act employment monitoring is a legal requirement for the two universities. The paper concludes by noting that other UK higher education institutions should undertake monitoring as a means of implementing equal opportunities policy.     

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