Effects of load mass carried in a backpack upon respiratory muscle fatigue     

Mark Faghy  Sam Blacker  Peter I. Brown 《European Journal of Sport Science》2016,16(8):1032-1038

Purpose: The purpose of this study was to investigate whether loads carried in a backpack, with a load mass ranging from 0 to 20?kg, causes respiratory muscle fatigue. Methods: Eight males performed four randomised load carriage (LC) trials comprising 60?min walking at 6.5?km?h^?1 wearing a backpack of either 0 (LC₀), 10 (LC₁₀), 15 (LC₁₅) or 20?kg (LC₂₀). Inspiratory (P_Imax) and expiratory (P_Emax) mouth pressures were assessed prior to and immediately following each trial. Pulmonary gas exchange, heart rate (HR), blood lactate and glucose concentration and perceptual responses were recorded during the first and final 60?s of each trial. Results: Group mean P_Imax and P_Emax were unchanged following 60-min load carriage in all conditions (p?>?.05). There was an increase over time in pulmonary gas exchange, HR and perceptions of effort relative to baseline measures during each trial (p?p?>?.05). Conclusions: These findings indicate that sub-maximal walking with no load or carrying 10, 15 or 20?kg in a backpack for up to 60?min does not cause respiratory muscle fatigue despite causing an increase in physiological, metabolic and perceptual parameters.  相似文献   

Lower limb alignment characteristics are not associated with running injuries in runners: Prospective cohort study     

Luiz Carlos Hespanhol Junior  Aline Carla Araújo de Carvalho  Leonardo Oliveira Pena Costa 《European Journal of Sport Science》2016,16(8):1137-1144

There is conflicting evidence on the association between lower limb alignment characteristics and the incidence of running-related injury (RRI). Therefore, the primary aim of this study was to investigate the association between lower limb alignment characteristics and the incidence proportion of RRI in a convenience sample of recreational runners. A total of 89 recreational runners were included in this prospective cohort study. These participants had been running for at least six months and were injury-free at baseline. Lower limb alignment measurements were conducted in order to calculate lower limb discrepancy, Q-angle, subtalar angle and plantar index. All participants also answered a baseline and biweekly online surveys about their running routine, history of RRI and newly developed RRI over a period of 12 weeks. The prevalence of previous RRI and the 12-week incidence proportion of new RRI were calculated. Logistic regression analysis was performed to estimate the association between lower limb length discrepancy, Q-angle, subtalar angle and plantar ach index with the incidence proportion of RRI. The prevalence of previous RRI was 55.1% (n?=?49). The 12-week incidence proportion of new RRI was 27.0% (n?=?24). Muscle injuries and tendinopathies were the main types of RRI identified. The lower leg and the knee were the main anatomical regions affected. We did not find significant associations between lower limb length discrepancy, Q-angle, subtalar angle and plantar arch index and injury occurrence.  相似文献   

What’s in a name: dimensions of social learning in teacher groups     

E. Vrieling  A. van den Beemt  M. de Laat 《Teachers and Teaching》2016,22(3):273-292

Induced by a literature review, this paper presents a framework of dimensions and indicators highlighting the underpinning aspects and values of social learning within teacher groups. Notions of social networks, communities of practice and learning teams were taken as the main perspectives to influence this social learning framework. The review exercise resulted in four dimensions: (1) practice, (2) domain and value creation, (3) collective identity and (4) organization. The indicators corresponding to these dimensions serve as the foundation for understanding social learning in practice. The framework of dimensions and indicators can be of assistance for researchers as well as teacher groups that aim to assess their views on social learning and analyse whether these views fit the learning goals of the group or that adjustments are required. In this way, learning processes within groups of teachers can be improved.  相似文献   

Education and social cohesion: developing a framework for education sector reform in Sri Lanka1     

Peter Colenso 《Compare》2005,35(4):411-428

There is increasing interest in understanding and describing the links between education and ‘social cohesion’. However, the theoretical and empirical base for understanding these links is limited. There is also a shortage of practical tools for education policy‐makers and planners, to help them assess the impact of policies and investments, and to plan for future reform. This paper describes the initial development of an analytical and planning framework for addressing education and social cohesion within the context of a sector‐wide approach to education reform in Sri Lanka. A brief literature review suggests three inter‐connected domains in which links between education and social cohesion might be usefully analysed, together with three working hypotheses: (i) political economy/governance: education affects social cohesion through transparency and participation in education policy formulation, planning and management; (ii) equity/equality of opportunity: education affects social cohesion through the distribution of education resources, opportunities and outcomes; (iii) teaching/learning: education affects social cohesion through the development of certain competencies in students. Drawing on this analytical framework, research conducted in Sri Lanka is used to identify a set of interventions to promote social cohesion, with corresponding baseline, process and outcome indicators as benchmarks for measuring the progress and impact of intended policy measures. This process is described within the context of a ‘sector‐wide approach’ to education reform, intended to bring together the activities of the government and external partners within a single comprehensive medium‐term planning and budgetary framework.  相似文献   

Explaining parents' school involvement: The role of ethnicity and gender in the Netherlands     

Fenella Fleischmann  Annabel de Haas 《The Journal of educational research》2016,109(5):554-565

  相似文献   

The Roles of Parental Support and Family Stress in Adolescent Sleep          下载免费PDF全文

Kim M. Tsai  Ronald E. Dahl  Michael R. Irwin  Julienne E. Bower  Heather McCreath  Teresa E. Seeman  David M. Almeida  Andrew J. Fuligni 《Child development》2018,89(5):1577-1588

The current study examines the association between parental support and adolescent sleep under varying levels of family stress. Participants included 316 adolescents (M_age = 16.40 years, 43% male) and their parents (M_age = 45.67 years, 91% mothers) from diverse ethnic backgrounds. Both adolescents and parents completed questionnaires and adolescents wore wrist actigraphs and completed self‐reports on their sleep for 7 consecutive days. Results indicated that under contexts of family stress, more parental support was linked to longer sleep duration, less sleep variability, and less time spent awake during the night. Findings suggest that under contexts of family stress, cohesive family relationships may provide a sense of stability and security that is necessary for healthful sleep.  相似文献   

Introduction to information processing and career development     

Andrew A. Helwig 《Journal of Career Development》1989,16(2):79-81

  相似文献   

Knowledge acquisition by computerized audiovisual feedback     

Fischer  Peter Michael  Mandl  Heinz 《European Journal of Psychology of Education - EJPE》1988,3(2):217-233

The present article gives an outline of the state of art in computer assisted intervention by learning-concomitant differential feedback. Based on the spectrum of possible meanings and interpretations given to the concepts ‘interaction’ and ‘interactive’ this concept is elaborated and illustrated by prototypical theoretical approaches. Based on our own empirical findings arguments are given showing that sophisticated audiovisual interactive new technologies can properly be used even on the small machines available in schools if the content materials and the flow of control given to the learner are carefully designed and based on principles of cognitive science.

  相似文献   

The study of butterflies     

Peter Smetacek 《Resonance》2001,6(5):8-15

In this part of the series on butterflies, we look at the types of variations found within species as well as their causes.  相似文献   

Comment: Reasoning with conditionals     

Peter F. W. Preece 《科学教学研究杂志》1993,30(9):1209-1210

  相似文献