Whole-body vibration training: Metabolic cost of synchronous, side-alternating or no vibrations

Abstract Whole-body vibration training improves strength and can increase maximal oxygen consumption ([Vdot]O(2max)). No study has compared the metabolic demand of synchronous and side-alternating whole-body vibration. We measured [Vdot]O(2) and heart rate during a typical synchronous or side-alternating whole-body vibration session in 10 young female sedentary participants. The 20-min session consisted of three sets of six 45-s exercises, with 15?s recovery between exercises. Three conditions wererandomly tested on separate days: synchronous at 35?Hz and 4?mm amplitude, side-alternating at 26?Hz and 7.5?mm amplitude (peak acceleration matched at 20?g in both vibration conditions), and no vibrations. Mean [Vdot]O(2) (expressed as %[Vdot]O(2max)) did not differ between conditions: 29.7?±?4.2%, 32.4?±?6.5%, and 28.7?±?6.7% for synchronous, side-alternating, and no vibrations respectively (P?=?0.103). Mean heart rate (% maximal heart rate) was 65.6?±?7.3%, 69.8?±?7.9%, and 64.7?±?5.6% for synchronous, side-alternating, and no vibrations respectively, with the side-alternating vibrations being significantly higher (P?=?0.019). When analysing changes over exercise sessions, mean [Vdot]O(2) was higher for side-alternating (P?相似文献   

Towards evidence-based classification in wheelchair sports: impact of seating position on wheelchair acceleration

In most Paralympic wheelchair sports, active trunk range of movement is assessed by observing shoulder girdle excursion during active trunk movements and is a key determinant of an athlete's class. However, to date research evaluating the impact of reduced trunk range of movement on wheelchair sports performance has not been conducted. In the present study, 15 non-disabled male participants performed two 20-s sprints on a wheelchair ergometer in each of three seating positions. Positions were typical of those used to enhance sitting stability in wheelchair sport and each impacted available trunk range of movement differently: condition-90 (seated with thighs horizontal; unrestricted range of movement) condition-45 (seated with thighs in 45°), and condition-0 (seated with hips maximally flexed; minimum range of movement). In condition-90, the trunk only actively contributed to the first push; for the remainder of the sprint, the trunk was held almost isometrically at 48.2° to the horizontal (range 42.1-56.4°). Similar patterns were observed for both condition-45 and condition-0. Compared with condition-90, participants in condition-0 had reduced capacity to accelerate of statistical (P < 0.05) and practical significance. These findings are an important initial step towards evidence-based decision making in classification. Future research should evaluate the individual and collective impact of other factors that affect the trunk's contribution to wheelchair sports performance, including strapping, seating position, and impairments of trunk muscle power and coordination.     

Study and research courses as an epistemological model for didactics

The aim of this paper is explain how the notion of “study and research course”, a recent construct in the anthropological theory of didactics, provides a general tool to model mathematical knowledge from a didactical perspective. We do this from two points of view. First, the notion itself arose as a tool for didactic design, particularly in mathematics teaching involving modelling type subjects, and we introduce a new diagrammatic representation in order to present and analyse a selection of such designs. Secondly, we demonstrate how the same representational tool can be used to analyse other didactic processes as study and research courses. In both cases, our examination of cases reveals that designers and teachers are often more explicit about their intention to enable students to do “research” (e.g. exploring a challenging problem) than to enable students to engage in autonomous “study”; moreover, the role for students is mostly confined to search for answers to questions raised, essentially, by the teacher. These observations point to directions which deserve more attention in design research related to the notion of study and research course.     

Report on the Evaluation of the Action 3.2 In-set Courses Organised Within the Framework of Action 3 of Comenius

The following article presents the results of the assessment of the Comenius courses run within Action 3, between the year 1996 and 1999. Different systems were used for the global evaluation, and were carried out before and after the courses, both by participants and organisers. They show positive and negative aspects, and there are suggestions for the improvement of the courses in the future. On the whole, the conclusion is that the courses are thought to be very positive and enriching.     

Differences in students' metacognitive strategy knowledge,motivation, and strategy use: A typology of self-regulated learners

Metacognitive strategy knowledge, motivation, and learning strategies play an important role in self-regulated learning (SRL). However, little is known about different profiles of self-regulated learners in schools that prepare students for the university entrance certificate. The aim of this study was to examine intraindividual differences in the patterns of students' SRL. In this 2-wave longitudinal study, 897 students were involved. Latent class analyses revealed four-cluster solutions at the beginning as well as at the end of the school year. Maximal self-regulated learners with the highest levels on all cognitive, metacognitive, and motivational components of SRL reported the highest grades in the academic subject of German (first language) at both measurement points, followed by motivated and strategic learners. Students with a low level on several SRL components reported the lowest grades. Further, the results indicated changes in profiles of SRL over time.     

How french and German children of preschool age conceptualize the writing system

As a continuation of research carried out by E. Ferreiro, we adopted a socio-constructivist approach to the question of how young children of 5–6 years of age conceptualize the writing system taking into account both their social background and their preschool system of education. Our sample was made up of 308 children of preschool level; 225 French children and 83 German children were asked to write a series of words without the help of a model. p The results we obtained confirmed our hypotheses: the pedagogical activities used in the French infant schools did not help the children to conceptualize the writing system better than the game activities (which had nothing to do with writing) used in the German kindergartens. Furthermore, we found that the socio-cultural background played an important role in both countries. The influence of the prevailing ideas about teaching and learning how to write, based on maturationism and empirism-associationism, are discussed with reference to the constructivist model.