The effects of work – rest duration on intermittent exercise and subsequent performance

This study examined the effects of different work?–?rest durations during 40?min intermittent treadmill exercise and subsequent running performance. Eight males (mean?±?s: age 24.3?±?2.0 years, body mass 79.4?±?7.0?kg, height 1.77?±?0.05?m) undertook intermittent exercise involving repeated sprints at 120% of the speed at which maximal oxygen uptake (v-[Vdot]O_2max) was attained with passive recovery between each one. The work?–?rest ratio was constant at 1:1.5 with trials involving short (6:9?s), medium (12:18?s) or long (24:36?s) work?–?rest durations. Each trial was followed by a performance run to volitional exhaustion at 150% v-[Vdot]O_2max. After 40?min, mean exercise intensity was greater during the long (68.4?±?9.3%) than the short work?–?rest trial (54.9?±?8.1% [Vdot]O_2max; P?<?0.05). Blood lactate concentration at 10?min was higher in the long and medium than in the short work?–?rest trial (6.1?±?0.8, 5.2?±?0.9, 4.5?±?1.3?mmol?·?l^?1, respectively; P?<?0.05). The respiratory exchange ratio was consistently higher during the long than during the medium and short work?–?rest trials (P <?0.05). Plasma glucose concentration was higher in the long and medium than in the short work?–?rest trial after 40?min of exercise (5.6?±?0.1, 6.6?±?0.2 and 5.3?±?0.5?mmol?·?l^?1, respectively; P?<?0.05). No differences were observed between trials for performance time (72.7?±?14.9, 63.2?±?13.2, 57.6?±?13.5?s for the short, medium and long work?–?rest trial, respectively; P = 0.17), although a relationship between performance time and 40?min plasma glucose was observed (P?<?0.05). The results show that 40?min of intermittent exercise involving long and medium work?–?rest durations elicits greater physiological strain and carbohydrate utilization than the same amount of intermittent exercise undertaken with a short work?–?rest duration.     

低碳发展方案编制指南(第三部分)——制定低碳发展规划

本节介绍制定低碳发展计划常用的核心步骤。本指南侧重城市层面;同样的步骤也适用于企业、市、省和国家等层级。中国自"十一五规划"起,对改善国内能源强度定出目标,包括各经济部门的节能目标。2009年12月中国政府公布了其碳强度目标,重点放在单位GDP用能引发的二氧化碳排放量。为实现该强度目标以及"循环经济"等经济性目标,制定低碳发展规划尤其必要。     

The effects of work:rest duration on physiological and perceptual responses during intermittent exercise and performance

Abstract

In this study, we examined the effects of different work:rest durations during 20 min intermittent treadmill running and subsequent performance. Nine males (mean age 25.8 years, s = 6.8; body mass 73.9 kg, s = 8.8; stature 1.75 m, s = 0.05; [Vdot]O_2max 55.5 ml · kg^?1 · min^?1, s = 5.8) undertook repeated sprints at 120% of the speed at which [Vdot]O_2max was attained interspersed with passive recovery. The work:rest ratio was constant (1:1.5) with trials involving either short (6:9 s) or long (24:36 s) work:rest exercise protocols (total exercise time 8 min). Each trial was followed by a performance run to volitional exhaustion at the same running speed. Testing order was randomized and counterbalanced. Heart rate, oxygen consumption, respiratory exchange ratio, and blood glucose were similar between trials (P > 0.05). Blood lactate concentration was greater during the long than the short exercise protocol (P < 0.05), whereas blood pH was lower during the long than the short exercise protocol (7.28, s = 0.11 and 7.30, s = 0.03 at 20 min, respectively; P < 0.05). Perceptions of effort were greater throughout exercise for the long than the short exercise protocol (16.6, s = 1.4 and 15.1, s = 1.6 at 20 min, respectively; P < 0.05) and correlated with blood lactate (r = 0.43) and bicarbonate concentrations (r = ?0.59; P < 0.05). Although blood lactate concentration at 20 min was related to performance time (r = ?0.56; P < 0.05), no differences were observed between trials for time to exhaustion (short exercise protocol: 95.8 s, s = 30.0; long exercise protocol: 92.0 s, s = 37.1) or physiological responses at exhaustion (P > 0.05). Our results demonstrate that 20 min of intermittent exercise involving a long work:rest duration elicits greater metabolic and perceptual strain than intermittent exercise undertaken with a short work:rest duration but does not affect subsequent run time to exhaustion.     

Joggers versus Nonexercisers: An Analysis of Knowledge,Attitudes and Beliefs about Jogging

Abstract

The Health Belief Model was utilized to examine the knowledge, attitudes and beliefs of individuals regarding regular jogging. Based on an elicitation procedure developed by Martin Fishbein, a questionnaire was developed according to the theoretical tenets of the Health Belief Model and was found to be valid and reliable. Responses from 124 joggers and 96 nonexercisers were analyzed, and significant differences were found. Factors which accounted for the largest portion of predictable variance (40%) were barriers to action such as lack of time, job or family responsibilities, or weather constraints. As a whole, the results provided support for the Health Belief Model in that 61% of the variance in jogging behavior was determined. The study suggests that physical and health educators might more effectively change the behavior of sedentary individuals by utilizing strategies which address perceived obstacles to jogging.     

The relevance of innovative school architecture for school principals

In many cases, innovative forms of learning require innovative concepts of using space in school. However, so far there has been a lack of research concerning the perspectives of school principals as important stakeholders in the adoption of alternative school architecture. The present study examines the importance of alternative school architecture in a sample of 1164 principals (56% females, mean-age 52.7 years) in Austria. An online questionnaire was conducted, containing questions about the school building, innovative forms of learning, and principals’ level of information, perceptions, and thoughts on the relevance of school architecture, as well as their motivation and self-efficacy. Results showed that principals are aware of the advantages of certain architectural elements, although these elements have been implemented in only a few schools. A high proportion of respondents report a lack of information about configurations of space that go beyond the traditional corridor-scheme. We conclude that although principals are in general open for the alternative configuration of space further efforts have to be made to overcome the obstacles that prevent principals from launching new concepts of using space, which are a lack of competitive resources and knowledge as well as an inadequate professional network.     

The Influence of Teacher Expectations about Twice-Exceptional Students on the Use of High Quality Gifted Curriculum: A Case Study Approach

Twice-exceptional students show evidence of high academic performance or potential and also have a disability that impedes their ability to learn. Twice-exceptional students remain under-represented in gifted programs, and some researchers attribute such under-representation to the negative beliefs and low expectations about twice-exceptional students held by teachers. While researchers have begun to investigate the curricular models and instructional strategies that are effective for twice-exceptional students, little research addresses how teacher beliefs and expectations about student ability are reflected in the ways teachers implement such models and strategies for twice-exceptional students in gifted classrooms. Even less research addresses gifted students with emotional and behavioral disabilities. We used a case study of a third-grade teacher using a structured, model-based language arts curriculum to better understand how her expectations about a gifted student with an emotional disability influenced her instructional choices. Using observational and interview data, the case study approach allowed the researchers to personalize the experiences of this teacher and provided a context in which to examine the subtleties of teacher expectations when teaching a gifted student with an emotional disability. Implications for educational practice, particularly the need for comprehensive school-based support systems for students with emotional disabilities, are discussed.     

Assessing semantic-syntactic features of verbs from thirteen verb subsets

There are three major classes of verbs: intransitive, transitive, and linking. These three types of verbs can be divided into 13 semantic-syntactic subsets. Verbs within each subset give rise to sentences that have similar syntactic form, albeit a form distinct from that of sentences associated with other subsets. Preliminary research found that more than 90% of sentences written by children or for children contain verbs from 1 of the 13 verb subsets. The sentence form associated with each verb subset might be viewed as a "sentence template" that operationally defines a fixed set of 13 underlying semantic-syntactic relationships essential to communication. A strategy for assessing a child's knowledge of verbs from each subset is described.     

Building classroom community at a distance: A case study

The purpose of this study was to analyze a five-week graduate-level education course taught entirely at a distance via the Internet using the Blackboard.com^SM e-learning system, with emphasis on exploring the dynamics of sense of classroom community. Subjects were 20 adult learners, evenly divided between males and females, who were administered the sense of classroom community index at the beginning and end of the course in order to measure classroom community. Findings indicated that on-line learners took advantage of the “learn anytime” characteristics of the Internet by accessing the course seven days per week, 24 hours per day. Sense of classroom community grew significantly during the course. Females manifested a stronger sense of community than their male counterparts both at the start and end of the course. Additionally, female students exhibited a mostly connected communication pattern while the communication pattern of males was mostly independent.     

Teaching with technology in higher education: understanding conceptual change and development in practice

Research indicates that teachers’ conceptions of and approaches to teaching with technology are central for the successful imple-mentation of educational technologies in higher education. This study advances this premise. We present a 10-year longitudinal study examining teachers’ conceptions of and approaches to teaching and learning with technology. Nine teachers on an online Bachelor of Science in Pharmacy and a Master of Pharmacy programme at a Swedish university were studied using a phenomenographic approach. Results showed clear differences between novice and experienced teachers. Although novice teachers initially held more teacher-focused conceptions, they demonstrated greater and more rapid change than experienced colleagues. Experienced teachers tended to exhibit little to no change in conceptions. Supporting conceptual change should, therefore, be a central component of professional development activities if a more effective use of educational technology is to be achieved.