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Background: Greater understandings about how progressive pedagogies are interpreted and practiced within schools will be required if international calls to enhance relevance and meaning in Health and Physical Education (HPE) are to be realised. Little is understood about how inquiry-based units of work connected to real-life issues are enacted, engaged with, and generate deeper knowledge within a HPE context.

Purpose: This study explores learner outcomes and perceptions of engagement with an inquiry-based unit of work, Take Action, that aimed to provide young people with an opportunity to critically reflect on movement, investigate an issue important to them, and enhance their capacity to enact positive change for themselves and others.

Participants and setting: Forty-four students and three teachers from two secondary school settings participated in the research. Both schools were located in relatively low socio-economic status areas in southern metropolitan Melbourne, Victoria, Australia.

Data collection and analysis: An exploratory and evaluative study design that employed naturalistic inquiry, using qualitative semi-structured interview data, observational data, and analysis of learner-produced artefacts were used. Analysis drew upon authentic learning frames to explore elements of knowledge construction through disciplined inquiry and real-life application.

Findings: Take Action provided a unique experience of HPE for the students and teachers who engaged with it. It was a collaborative, learner-centred inquiry-based experience that most learners found to be engaging and authentic. Both teachers and learners lacked the foundational knowledge of the discipline and a sound understanding of a critical-inquiry process that would have allowed them to deconstruct and reconstruct new ideas in deep interconnected ways.

Conclusions: More support for teachers and students is needed to legitimate these types of approaches within broader curriculum contexts to support student learning. Specifically, foundational understandings of: socially critical approaches to critical inquiry that serve to enhance knowledge relating to learner-identified topics; learning intentions and authentic assessment and how these might align with inquiry-based learning; forming connections with external experts to support learners early in an inquiry process; and how to extend explorations and elaborations within the constraints of a congested and contested curriculum.  相似文献   


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Purpose: The aim of this study was to review the effect of school-based physical activity interventions on children’s wellbeing.

Method: A systematic search of school-based physical activity studies was conducted using EBSCOhost PsycInfo, EBSCOhost Medline and Web of Science. Initially 995 studies were retrieved and, following the removal of duplicates, the titles and abstracts of 984 studies were screened. This screening identified 53 relevant studies from which 42 were excluded, resulting in 11 articles being reviewed.

Results: Three studies reported a positive increase in wellbeing; however, only one of those studies also significantly increased physical activity. It was apparent that the measurement of wellbeing and physical activity was inconsistent across studies, making conclusions difficult to draw. The wellbeing measures used neglected to account for the children’s perspectives of wellbeing.

Conclusions: The effect of a physical activity intervention on increasing wellbeing appears to be more complex than originally believed. The complexity may in part be due to methodological issues and the choice of wellbeing and physical activity measurement. We recommend that future physical activity interventions include a measure of wellbeing developed from the child’s perspective, and that future reviews narrow the search to only interventions that have had success at increasing physical activity before exploring effects on wellbeing.  相似文献   


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Background: Physical educators currently have a number of pedagogical (or curricular) models at their disposal. While existing models have been well-received in educational contexts, these models seek to extend students’ capacities within a limited number of ‘human activities’ (Arendt, 1958). The activity of human practising, which is concerned with the improvement of the self, is not explicitly dealt with by current models.

Purpose: The aim of the paper is to outline how a model of human practising related to movement capability could be enacted in physical education.

Findings: Building on a theoretical exposition of human practising presented in a separate paper, this paper provides a practically oriented discussion related to: (1) the general learning outcomes as well as teaching and learning strategies of the model; (2) an outline of five activities that describe how the model could be implemented; and (3) the non-negotiable features of the model.

Discussion: The model’s potential contribution to the ongoing revitalization of PE as an institutionalized educational practice is discussed. Points concerning how the model relates to wider physical cultures, its position regarding transfer of learning, standards of excellence, and social and cultural transmission are considered.

Conclusion: The paper is concluded with some reflections on pedagogical models generally and how they relate to the pedagogical model of practising movement capability presented in this paper.  相似文献   


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Background: Physical education has historically been a repressive place for queer persons. Since physical education spaces are predominantly heteronormative, research on sexual identity management has shown lesbian teachers often try to ‘pass’ as straight or distance themselves from their sexualities. There has been no research to date that examines the experiences of queer male physical educators.

Purpose: The purpose of this paper is to use Deleuzo-Guattarian theory to reflect on my affective experiences as a queer male physical educator. A secondary goal is to transcend binary theorising that has shaped previous research in the field.

Design and Analysis: This paper uses autoethnographic examination to analyse experiences as a queer male physical educator. Data consists of narratives from my first year as a physical educator. These narratives are analysed using Deleuzo-Guattarian theory to map their affective implications.

Conclusion: I conclude the paper by reflecting on and recommending several initiatives that can help shift our field toward a Queer Inclusive Physical Education.  相似文献   


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Running has been plagued with an alarmingly high incidence of injury, which has resulted in the exploration of interventions aimed at reducing the risk of running-related injury. One such intervention is the introduction of footwear that mimics barefoot running. These have been termed minimalist shoes.

Minimalist footwear aims to reduce the risk of injury by promoting adaptations in running biomechanics that have been linked to a reduction in both impact and joint forces. However, some studies have found that minimalist footwear may be beneficial to the runner as they promote favourable biomechanical adaptations, whilst other studies have found the opposite to be true.

Reasons for these conflicting results could be attributed to the lack of a definition for minimalist footwear. The aim of this review article is to provide a structural definition for minimalist footwear based on studies that have examined the influence of footwear on biomechanical variables during running.

Based on current literature, we define minimalist footwear as a shoe with a highly flexible sole and upper that weighs 200g or less, has a heel stack height of 20mm or less and a heel-toe differential of 7mm or less.  相似文献   


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Background: During the socialization process when becoming a physical education (PE) teacher, the knowledge, perceptions and expectations of what it means to work as a teacher are developed. In this socialization, the initial acculturation phase is shown to be of the most importance, since individual PE teachers’ experiences during this phase are shown to have a long-lasting influence on their approach to and perception of the subject and the profession. Furthermore, research shows that most physical education teacher education (PETE) programmes are ineffective in altering these initial perceptions and beliefs during the programme. This inertia to change may resemble Bourdieu’s concept of habitus.

Purpose: The purpose of this study was to analyse the background of PE preservice teacher students (PSTs) and examine their embodied perceptions and beliefs related to the subject and profession when they enrol. Specifically, the study focuses on their background characteristics, perceptions of PE and PE teachers, and whether their background and perceptions changed between 2005 and 2016.

Method: This study draws on a web-based questionnaire completed by 224 students (90 women and 134 men) enrolled in the PETE programme at a major university in Sweden between 2005 and 2016. The questionnaire used in this study addressed the PSTs’ experiences, views, beliefs and perceptions of PE and the PE profession, and it was completed during the first semester of respective students’ PE subject studies.

Findings: PE PSTs are a homogeneous group of students with similar backgrounds, experiences and perceptions of PE and their future profession as PE teachers. Participants suggested that important characteristics for a good PE teacher include possessing subject knowledge, having pedagogical competence and being considerate. A good PE lesson should be fun and inspiring, consist of physical activity and be adapted to all. Important goals for PE are to develop pupils’ character and promote healthy behaviours. The PSTs’ background characteristics and perceptions do not seem to have changed during the studied period, in spite of the fact that the structure of the PETE programme did change.

Conclusions: The homogeneous background among PSTs, with vast experience of sport and physical activity, implies that they will interact and engage with students with similar backgrounds and perceptions (i.e. habitus) during PETE. This may limit the potential influence of PETE and fail to prepare PSTs for the demands of their future profession. However, if the influences of acculturation were accounted for during PETE, the programmes could be better designed and better prepare PSTs for their future profession.  相似文献   


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Background: Models-based approaches to physical education have in recent years developed as a way for teachers and students to concentrate on a manageable number of learning objectives, and align pedagogical approaches with learning subject matter and context. This paper draws on Hannah Arendt’s account of vita activa to map existing approaches to physical education as oriented towards: (a) health and exercise, (b) sport and games, and (c) experience and exploration.

Purpose: The aim of the paper is to outline a new pedagogical model for physical education: a practising model. We argue that the form of human activity related to practising is not well represented in existing orientations and models. To sustain this argument, we highlight the most central aspects of practising, and at the same time describe central features of the model.

Relevance and implications: The paper addresses pedagogical implications the practising model has for physical education teachers. Central learning outcomes and teaching strategies related to four essential and ‘non-negotiable’ features of the practising model are discussed. These strategies are: (1) acknowledging subjectivity and providing meaningful challenges, (2) focusing on content and the aims of practising, (3) specifying and negotiating standards of excellence and (4) providing adequate time to practising.

Conclusion: The practising model has the potential to inform new perspectives on pedagogical approaches, and renew and improve working methods and learning practices, in physical education.  相似文献   


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Background: Achieving teacher change and the lofty goals of educational reform initiatives necessitates professional development (PD) designed to help teachers rethink their practice. A key implication for physical education, therefore, is that PD must be organized in ways that utilize teachers' voice, providing opportunities for teachers to build or extend their own capacity to engage in ongoing learning. Yet, while the desired outcome of PD is capacity-building resulting in teacher change, teachers' needs and interests remain largely ignored.

Purpose: The purpose of this study was to explore the potential of using participatory visual methods as a pedagogical and methodological tool to facilitate teacher articulation of change. Specifically, we sought to understand teachers' depictions of their own change.

Theoretical framework: The project was grounded in constructivist learning theory as the pedagogical use of visual methods provided teachers a way to understand, interpret, and think about the curriculum change and their teaching.

Participants and setting: Four physical education teachers, all female, were the participants.

Data sources: Data sources included (a) participants' digital photographs, (b) photo-elicitation interviews, and (c) field notes from observations of all PD sessions, conference presentations, and multiple lessons taught by the teachers.

Data analysis: Data were analyzed using two distinct yet overlapping processes derived from grounded theory: open and axial coding.

Findings: Visual methods allowed participants to articulate three distinct changes as a result of the curriculum development PD process: (a) changes in practice, (b) changes to interpersonal working relationships, and (c) intrapersonal changes. First, the use of visual methods allowed these teachers to identify four multidimensional student learning-focused changes to their teaching practice: outcomes based instruction, increased and differentiated practice, deliberate focus on the affective domain, and assessment to document learning. Second, changes to interpersonal working relations as a result of the curriculum development were documented. These changes provided the initial forum for collaboration as well as solidarity among the teachers to complete a defined task. Third, empowered by their increased skills and knowledge, these teachers experienced intrapersonal changes as they embraced their roles as teachers, professionals, and leaders. All four teachers expressed increased sense of self as a result of their changes in curriculum, assessment, and approach to teaching.

Conclusions: These teachers accomplished a great deal as they departed from what they knew well to try new practices and strategies. The use of visual methods documented this complex process. This study has several implications for the use of visual methods. The first is their value as a way for teachers to discuss their own learning and reflect on their practice. Second, the use of photographs and associated photo-elicitation interviews served as a valid research tool which successfully accessed teachers' implicit learning. Finally, a combination of methodologies provided different, yet complimentary information about teachers' depictions of change.  相似文献   


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When children or adolescents are grouped by age or year of birth, older individuals tend to outperform younger ones. These phenomena are known as relative age effects (RAEs). RAEs may result directly from differences in maturation, but may also be associated with psychological, pedagogic or other factors. In this article, we attempt to quantify RAEs in a simple fitness task and to identify the mechanisms operating.

Data come from a 5-year study of 2278 individuals that included repeated administrations of the 20 m shuttle run. We use mixed-effect modelling to characterise change over time and then examine residuals from these models for evidence of an effect for age relative to peers or for season of birth.

Age alone appears to account for RAEs in our sample, with no effects for age relative to peers or month of birth. Age grouping produces large disparities for girls under 12, moderate ones for boys of all ages and negligible ones for girls between 12 and 15.

RAEs for this task and population appear to arise from simple age differences. Similar methods may be useful in determining whether other explanations of RAEs are necessary in other contexts. Evaluation processes that take age into account have the potential to mitigate RAEs in general settings.  相似文献   


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Rugby union is a sport governed by the impacts of high force and high frequency. Analysis of physiological markers following a game can provide an understanding of the physiological response of an individual and the time course changes in response to recovery.

Urine and saliva were collected from 11 elite amateur rugby players 24 h before, immediately after, and at 17, 25, 38, 62 and 86 h post-game. Myoglobin, salivary immunoglobulin A and cortisol were analysed by ELISA, whereas neopterin and total neopterin were analysed by high-performance liquid chromatography.

There was a significant post-game increase of all four markers. The increases were cortisol 4-fold, myoglobin 2.85-fold, neopterin 1.75-fold and total neopterin 2.3-fold when corrected with specific gravity. All significant changes occurred post-game only, with markers returning to and remaining at baseline within 17 h.

The intensity of the game caused significant changes in key physiological markers of stress. They provide an understanding of the stress experienced during a single game of rugby and the time course changes associated with player recovery. Neopterin provides a new marker of detecting an acute inflammatory response in physical exercise, while specific gravity should be considered for urine volume correction post-exercise.  相似文献   


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Background: Many alternative curricular models exist in physical education to better meet the needs of students than the multi-activity team sports curriculum that dominates in the USA. These alternative curricular models typically require different content knowledge (CK) and pedagogical CK (PCK) to implement successfully. One of the complexities of learning to teach these models for pre-service teachers (PTs) is understanding the different CK and PCK required which is compounded by their personal lack of experience of the model.

Purpose: The purpose of this study was to explore the PCK enacted by PTs learning to teach an alternative curricular model (adventure-based learning [ABL]) in urban middle schools.

Research design: Qualitative methods were used to explore how the PTs demonstrated their PCK while teaching an ABL unit to urban middle school students. The study took place at a major university and in three middle schools in a large urban school district in Midwestern USA.

Participants: Thirteen PTs enrolled in the secondary methods course and associated internship agreed to participate in this study. The PTs (five males and eight females) ranged in age from 21 to 26 years and all self-identified as white.

Data collection and data analysis: Three methods of data collection were employed in this study: interviews, daily reflections called critical friends, and stimulated recall reflection of teaching an ABL lesson. Data were analyzed using constant comparison. Trustworthiness was established through triangulation of the data using multiple data sources, peer debriefing, member checking, and negative case analysis.

Findings: Four themes represented the PTs' demonstration of PCK when learning to teach ABL in urban middle schools. The themes were (a) trusting the sequence, (b) knowing your students, (c) facilitate don't dictate, and (d) processing the experience. The findings provide further insight into the demonstration of PTs' PCK in secondary physical education, and specifically relative to teaching ABL in urban middle schools. To better equip PTs to be able to teach using these models, we recommend the following: (a) they have the opportunity to ‘live the curriculum' in their PETE programme, (b) developing the PTs' specific CK and student-centered pedagogical knowledge for specific alternative curricular models is imperative in developing the PCK for such model, (c) developing PTs' knowledge of students relative to the complexities of learning to teach each specific model, (d) observing an expert teach the model to K-12 students, and (e) recognizing that learning to teach these models is a developmental process and providing the PTs with an emotionally safe and caring space to explore teaching such models is crucial.  相似文献   


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Background: Research indicates that physical education teacher education (PETE) has only limited impact on how physical education (PE) is taught in schools. In this paper, our starting point is that the difficulties of challenging the dominating subject traditions in PE could be due to difficulties of challenging certain epistemological assumptions recurring in significant PETE subject matter and didactics courses.

Purpose: The purpose of this paper is to scrutinise how knowledge is expressed in learning outcomes formulated in curriculum documents at PETE institutions in Sweden and to discuss the potential educational consequences of the epistemological assumptions underlying the analysed expressions of knowledge.

Setting and participants: This paper offers possible explanations for the difficulties of influencing subject traditions in PE through analysing learning outcomes formulated in PETE curriculum documents. The analysis is based on 224 learning outcomes collected from a total of 18 course syllabi, spread at 6 PETE institutions in Sweden.

Research design, data collection and analysis: The documents have been collected through contact by e-mail with representatives for each institution. Through the analysis different themes in the material have been identified and clustered together. Inspired by Fenstermacher's ideas about teacher knowledge as propositional knowledge and performance knowledge, our ambition is to discuss the potential educational consequences of the epistemological assumptions underpinning the analysed learning outcomes.

Findings: In the collected learning outcomes, the following themes were identified: teaching PE, interpreting curriculum documents, physical movement skills, science, social health, pedagogy, critical inquiry, and research methods. In most of the identified themes, the learning outcomes represent both subject matter knowledge and general teacher knowledge and are also formulated with an integrated perspective on so-called performance knowledge and propositional knowledge. However, particularly in the themes science and physical movement skills, two very influential themes, the learning outcomes are limited to subject matter knowledge and the concept of knowledge in these themes is also limited and unilateral in relation to ideas of different forms of teacher knowledge.

Conclusions: We argue that a decontextualisation of knowledge, in this paper identified through dissolving science from its use in practice and through detaching physical movement skills from other conceptual foundations, contributes to the reproduction of subject traditions that render PE teachers incapable of critically reflecting over their practice, for instance how different groups of students benefit or suffer from the teaching of certain content. Drawing on the work of Tinning, we offer an explanation as to how teacher knowledge in the themes science and physical movement skills, emanating from behaviouristic and craft knowledge orientations, is formulated.  相似文献   


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Background: Noteworthy proportions of adolescents – particularly females – report negatively about their experiences regarding fitness and the testing of it during physical education (PE). These accounts often coincide with lower levels of body image, fitness, motivation, and physical activity and higher rates of attrition from optional PE.

Purpose: The aim of this study was to test path relations between body size dissatisfaction (BSD), test anxiety (TA), self-efficacy, and fitness-related outcomes during fitness in PE and to determine whether these differ as a function of gender and level of BSD.

Method: Survey data were collected from 394 9th and 10th-grade students in southern Ontario, Canada. A previously validated BSD measure was used that consisted of a series of nine gender-specific silhouettes ranging from very thin/slender to very large/overweight. Students’ dissatisfaction score involved subtracting self-ratings of their ideal body size from current body size estimates. Fitness indices in PE (FIPE)was the z-score of the sum of self-reported fitness level, fitness grade in PE, and frequency of active exercise at least 30 minutes per day. Self-efficacy and TA were assessed using established scales from the Motivated Strategies for Learning Questionnaire.

Data analysis: Multivariate analysis of variance was used to assess group differences whereas gender-specific confirmatory factor and path analyses were used to test the proposed path in which relations between BSD and FIPE were manifest indirectly through TA and self-efficacy.

Findings: The hypothetical path fit the data in the overall sample and fit better for females than for males. Females reported a higher BSD and a lower self-efficacy and FIPE than males. BSD was evident in both genders with most females desiring a thinner body compared to boys who had relatively equal proportions wanting to be bigger and thinner. Males wanting to be smaller reported significantly lower self-efficacy and FIPE than males with little BSD or those wanting to be larger. Females desiring a thinner body reported significantly more TA and lower FIPE than females with no BSD.

Conclusion: Body image concerns and elevated levels of anxiety appear to undergird the influence of self-efficacy on FIPE. This is particularly so in females, although both females and males with a BSD are susceptible to lowered fitness motivation and achievement in PE. Suggestions are provided to help physical educators to structure fitness curricula and pedagogy to better minimize this vulnerability. These include catering to the gender-specific needs and preferences for fitness activities during PE including the testing of fitness.  相似文献   


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Background: Student-Centered Inquiry as Curriculum (SCIC) is an activist approach [Oliver, K. L., and H. A. Oesterreich. 2013. Student-Centered Inquiry as Curriculum as a Model for Field-Based Teacher Education. Journal of Curriculum Studies 45 (3): 394–417. doi:10.1080/00220272.2012.719550] inspired by years of research with youth. It was designed as a means of listening and responding to youth in order to better facilitate students’ interest, motivation, and learning in physical education settings. While we have a strong and growing body of activist research with youth in physical education, SCIC as a specific approach to working with youth is in its infancy; thus, there is a need to further explore the challenges teachers/researchers face learning to use this approach to teaching.

Purpose: This study explores how educators, in different contexts, learn to use an activist approach called SCIC, in order to better facilitate students’ interest, motivation, and learning in physical education and physical activity settings.

Research setting and participants: Participants included a university professor, a college instructor, a postdoctoral student, a doctoral student, and a pre-service teacher. Data were collected between January and May 2016.

Data collection and analysis: Data collection included weekly field notes and debriefings following observations, teacher artifacts, weekly collaborative group meetings, and two individual interviews per teaching participant.

Discussion and conclusions: The main challenge that emerged was learning how to move from a theoretical understanding of student-centered pedagogy to the practice of student-centered pedagogy. Specifically, the amount of time that was necessary to build a foundation that allowed for student and teacher understanding, respect, and comfort, negotiating teacher and student assumptions that were embedded in the status quo of physical education (PE), and the struggle to gather and use meaningful data to guide pedagogical decisions. We negotiated these challenges through our professional learning community whereby we worked to all be able to see and name what was happening in our individual classes and collectively planned what was needed to move forward through these challenges.  相似文献   


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Background: School Health and Physical Education (HPE) and sport has increasingly become a complex cultural contact zone. With global population shifts, schools need policies and strategies to attend to the interests and needs of diverse student populations. School HPE and sport is a particularly significant site as it is a touchpoint for a range of cultural values and practices related to physical activity, the body, health and lifestyle proprieties.

Purpose: While there is a high Chinese student population in Australian schools, little research has been undertaken to understand their needs, experiences and perceptions in schools HPE and sport. In addition, research in the physical activity field is accentuated by paradigms that assume and perpetuate the binary notion of cultural beliefs and practices such as ‘West’ versus ‘East’ and in association with ‘Normal’ versus ‘Problematic’ lifestyles in relation to physical activity. We argue that, without conceding the epistemological understanding of ‘difference’, policies and practices that promote diversity can remain socially unjust and superficial.

Research design: This paper focuses on two schools in Queensland. The data collection process was underpinned by critical and interpretive ethnographic methods. The participants in Sage College consisted of seven girls of whom three were in Year 8, three in Year 9 and one in Year 10. At Routledge State High, a state-owned, secular and coeducational secondary school, the cohort consisted of two girls in Year 8, one girl and two boys from Year 9.

Results: This paper draws on Bourdieu's concepts of habitus, capital, field and doxa and the Chinese Confucianism philosophy of ‘Complementary difference’ to understand the various perceptions and experiences of young Chinese Australians in schools HPE and sport. Results invite us to seek an understanding of students’ subjectivities and disrupt the binary differences in cultural values and attributes to promote multicultural education.

Conclusion and recommendation: Moving beyond the Australia's Anglo-Celtic centred HPE and the limitations of a Western view of exclusive opposites, this paper makes an original contribution to knowledge by presenting a ‘heuristic of difference’ model that accommodates Western and Chinese perspectives in Australian HPE research.  相似文献   


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Background: Previous studies of mastery motivational climates within physical education have reported that providing students with opportunities to become self-directed leads to a number of positive outcomes, including skill attainment and increased perceptions of ability. Nonetheless, within all of these studies, there has been no account of the teaching/learning process or the behaviour of the students and teachers within the various interventions.

Purpose: The purpose of this study was to provide a micro-analysis of life in a mastery climate which was grounded in the classroom ecology paradigm.

Participants and setting: The participants in this study were 13 children (11 boys and 2 girls) all aged 4 years at the commencement of the programme. The children were attendees at a day-care centre that serves mostly African-American children from the local community who are environmentally at risk for developmental delay and poor health. The teacher in this study was a faculty member at the university where the programme took place. For 30 minutes each Tuesday and Thursday, the children participated in a programme of motor skill instruction that was based upon the key principles of a mastery-motivational climate. Selected station activities were designed to promote the acquisition of locomotor and object control skills.

Methods: A mixed-methods approach was taken, with data sources including interviews with the teacher, and an analysis of the ecology of the gymnasium using a modified version of the task structure system. Focus was placed upon the task goals, the teacher's accountability strategies, as well as task accomplishment in both the managerial and instructional task systems.

Findings: The key finding from this study was an appreciation of how time is a significant factor in the ways in which children initially responded to and eventually embraced the freedoms afforded to them in a mastery climate. Of particular note, the results show substantial differences in the children's lesson engagement not only across time, but also within lessons themselves. It is hypothesized that as they progressed through the programme, the children not only were more able to identify the demands of the task but were also able to filter out extraneous signals that might promote off-task or inappropriate behaviour.

Conclusions: The design of this study reinforced the value of adopting an ecological analysis of life in a mastery climate. Further, the results of the study showed the value of examining young children's engagement over a lengthy intervention. While such climates are expected to have lower levels of engagement and higher levels of off-task behaviour than more teacher-directed formats, by the end of the study the children were able to achieve levels of appropriate task engagement above 80% of lesson time.  相似文献   


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Although a low rolling resistance is advantageous in mountain bike cross-country racing, no studies have used the virtual elevation method to compare tyres from different manufacturers as used in international competitions so far. The aims of this study were to assess the reliability of this method, to compare the off-road rolling resistance between tyres and to calculate the influence on off-road speed.

Nine 29-in. mountain bike cross-country tyres were tested on a course representing typical ground surface conditions 5 or 6 times. The coefficient of rolling resistance was estimated with the virtual elevation method by 3 investigators and corresponding off-road speeds were calculated.

The virtual elevation method was highly reliable (typical error = 0.0006, 2.8%; limits of agreement <0.0005, r ≥ 0.98). The mean coefficient of rolling resistance was 0.0219 and differed from 0.0205 to 0.0237 (P < 0.001) between tyres. The calculated differences in off-road speed amounted to 2.9–3.2% (0% slope) and 2.3–2.4% (10% slope) between the slowest and the fastest tyre.

The reliability of the method and the differences in rolling resistance between the tyres illustrate the value of testing tyres for important competitions on a representative ground surface using the virtual elevation method.  相似文献   


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