Energy turnover during 24 hours and 6 days of adventure racing

Abstract

Energy turnover was assessed in two conditions of mixed ultra-endurance exercise. In Study 1, energy expenditure and intake were measured in nine males in a laboratory over 24 h. In Study 2, energy expenditure was assessed in six males during an 800-km Adventure race (mean race time 152.5 h). Individual correlations between heart rate and oxygen uptake ([Vdot]O₂) were established during pre-tests when kayaking, cycling, and running. During exercise, energy expenditure was estimated from continuous heart rate recordings. Heart rate and [Vdot]O₂ were measured regularly during fixed cycling work rates to correct energy expenditure for drift in oxygen pulse. Mean energy expenditure was 18,050 ± 2,390 kcal (750 ± 100 kcal · h^?1) and 80,000 ± 18,000 kcal (500 ± 100 kcal · h^?1) in Study 1 and Study 2 respectively, which is higher than previously reported. Energy intake in Study 1 was 8,450 ± 1,160 kcal, resulting in an energy deficit of 9,590 ± 770 kcal. Body mass decreased in Study 1 (?2.3 ± 0.8 kg) but was unchanged in Study 2. Fat mass decreased in Study 2 (?2.3 ± 1.5 kg). In Study 1, muscle glycogen content decreased by only 60%. Adventure racing requires a high energy expenditure, with large inter-individual variation. A large energy deficit is caused by inadequate energy intake, possibly due to suppressed appetite and gastrointestinal problems. The oxygen pulse, comparing start to 12 h of exercise and beyond, increased by 10% and 5% in Study 1 and Study 2 respectively. Hence, estimations of energy expenditure from heart rate recordings should be corrected according to this drift.     

Reformation of VET and demands on teachers’ subject knowledge – Swedish vocational teachers’ recurrent participation in a national CPD initiative

This study investigates continuing professional development (CPD) of vocational teachers, with a focus on recurrent participation. Vocational teachers need to be competent as teachers and in relation to their vocational teaching subject. Reformation of Swedish vocational education in order to strengthen the working-life connection imposes demands on teachers to have up-to-date knowledge about the vocations related to their vocational subjects. To support the reform, vocational teachers have been offered to participate in a new national CPD initiative targeting their vocational competence. The study concerns participation in this initiative. Drawing on a socio-cultural perspective, vocational teachers’ CPD implies boundary-crossing between school and working-life. Theory concerning adults’ participation in education is considered relevant to understand conditions for such boundary-crossing, and learning, among vocational teachers. The article specifically investigates patterns in vocational teachers’ recurrent participation, which is expected to clarify the factors influencing further participation in professional development. The strongest predictor of recurrent participation, when adjusting for the influence of other factors, is the type of municipality that the teacher comes from, with low populated municipalities having the lowest likelihood of participation. Furthermore, recurrent participation is more likely by participating teachers from adult education or from privately owned schools, and by male teachers.     

What disengages doctoral students in the biological and environmental sciences from their doctoral studies?

This study explored the causes of student disengagement from their doctoral studies in the biological and environmental sciences. The data came from interviews of 40 doctoral students (male?=?15, female?=?25) and underwent qualitative analysis for content. Our results showed that doctoral studies provide multiple contexts for disengagement, such as the scholarly community and supervision, while doctoral students’ sense of distress, cynicism and inefficacy emerged as central components of disengagement. The study identified isolation, indifference, and lack of support and constructive feedback as sources of cynicism, while distress and inefficacy were more often related to failure or lack of progress in research. Our findings indicate that the source of disengagement can vary not only between individuals, but also between the academic activities at hand. Thus, while promoting an engaging doctoral experience, awareness of what typically triggers disengagement in the doctoral journey is vital.     

A dynamic learning concept in early years’ education: a possible way to prevent schoolification

In early childhood education and care, Nordic social pedagogy approach is challenged by a learning orientation that often results in unproductive ‘either/or’ thinking. Therefore, based on the two approaches and by analysing several dimensions of Froebel’s ideas and prevailing social-historical activity (play) theory, the author deduces four generally accepted play criteria that form the basis for the construction of a dynamic and play-based learning concept that has the three following cornerstones as focal points: (1) learning happens in activities where the child is an active participant and interacts and communicates with other people; (2) meaningful activities pave the way for children’s learning; these are activities where the child’s motive aligns with the goal of the activity; and (3) learning is seen as a productive and creative activity characterised by imagination.     

Disparity in practice: diverse strategies among teachers implementing interactive whiteboards into teaching practice in two Swedish primary schools

This paper reports on a project aimed at identifying and exploring the development and implementation processes of teaching practices with interactive whiteboards (IWBs) in two Swedish K-6 schools. The purpose of the project was to generate results and insights of value when preparing student teachers for professional use of IWBs and to give school leaders guidelines when implementing IWBs. A range of methods were used to collect rich and varied empirical materials in this exploratory project. Judging from our data, it was obvious that the implementation process of IWBs, just like other information and communication technology initiatives, is very technology-oriented, but also dependent on attitudes. Over the course of time in the project, different strategies emerged among the teachers regarding whether and how they used the IWBs in their lectures. It also became increasingly clear during the study that there is a distinction between technical interactivity and pedagogical interactivity. Our results further suggest that training is needed when introducing these boards for future users. This training should include both technical instructions and pedagogical discussions.     

The Multiple Faces of Visual Arts Education

This article identifies recent, mainly Nordic, research approaches to visual arts education. A concept map was developed as a heuristic tool in order to highlight salient traits and blind spots. Contemporary research typically has its origin either in education or in the art world, with an emphasis either on art as language or on art as text. These two dimensions were used to organise the studies and to select representative exemplars in different domains. The framework helped to chart the knowledge base of, and research approaches to, visual arts education. However, the result of blending subject matter and pedagogy tended to be a ‘mixture’ of viewpoints rather than emerging domains of subject‐specific pedagogical knowledge (Lee Shulman: an ‘amalgam’).     

Correction to: The influence of SES,cognitive, and non-cognitive abilities on grades: cross-sectional and longitudinal evidence from two Swedish cohorts

It is well established that socioeconomic status, cognitive ability, and non-cognitive abilities such as self-efficacy are substantially associated with academic achievement. However, the specific relationships of these variables remain a relatively unexplored topic in regard to more recent and representative samples. The current study examined such relations by taking advantage of two cohorts (total N = 12,315) of Swedish students at the elementary (Grade 6) and lower-secondary school levels (Grade 8) in the compulsory school. The regression models showed that all three variables explained a substantial portion of grade variance, with cognitive ability having the strongest relationship, followed by non-cognitive abilities, and SES. Longitudinal associations, which accounted for previous academic achievement, showed that the three variables did still explain a substantial amount of grade variance.

     

Variation among schools on classroom practices in science based on TIMSS‐1999 in Turkey

The purpose of this study was to investigate the differences among schools using student responses in the Trends in Mathematics and Science Study–1999 (TIMSS‐99) data. Schools were classified into two groups based on eighth grade students' overall achievement in science. Two different discriminant function analyses were performed to distinguish high‐ and low‐performing schools, based both on classroom practices and factor structures (student‐centered activities, teacher‐centered activities, attitudes toward technology use, socioeconomic status [SES], and doing well in science). The results indicate that there were significant differences between the two classifications of schools on ten variables regarding classroom practices and activities, and 29 variables regarding classroom practices, attitudes toward science, use of the computer and overhead projector (OHP), parental background characteristics, and need to do well in science. Contrary to general expectations, technology use (computer, OHP, etc.) was found to be negatively related to science achievement. Teachers should be trained on how to use technology in their classrooms. Turkey recently revised its curriculum to a student‐centered approach and this might increase students' ability to transfer knowledge into real life. Teachers and schools should pay more attention to SES effects. Teachers should also work toward building students' confidence in science. © 2007 Wiley Periodicals, Inc. J Res Sci Teach 44: 1417–1435, 2007     

Effects of muscle-tendon length on joint moment and power during sprint starts

The aim of this study was to examine the effects of muscle-tendon length on joint moment and power during maximal sprint starts. Nine male sprinters performed maximal sprint starts from the blocks that were adjusted either to 40 degrees or 65 degrees to the horizontal. Ground reaction forces were recorded at 833 Hz using a force platform and kinematic data were recorded at 200 Hz with a film camera. Joint moments and powers were analysed using kinematic and kinetic data. Muscle - tendon lengths of the medial gastrocnemius, soleus, vastus medialis, rectus femoris and biceps femoris were calculated from the set position to the end of the first single leg contact. The results indicated that block velocity (the horizontal velocity of centre of mass at the end of the block phase) was greater (P < 0.01) in the 40 degrees than in the 65 degrees block angle condition (3.39 +/- 0.23 vs. 3.30 +/- 0.21 m . s(-1)). Similarly, the initial lengths of the gastrocnemius and soleus of the front leg in the block at the beginning of force production until half way through the block phase were longer (P < 0.001) in the 40 degrees than in the 65 degrees block angle condition. The initial length and the length in the middle of the block phase were also longer in the 40 degrees than in the 65 degrees block angle condition both for both the gastrocnemius (P < 0.01) and soleus (P < 0.01-0.05) of the rear leg. In contrast, the initial lengths of the rectus femoris and vastus medialis of the front leg were longer (P < 0.05) in the 65 degrees than in the 40 degrees block angle condition. All differences gradually disappeared during the later block phase. The peak ankle joint moment (P < 0.01) and power (P < 0.05) during the block phase were greater in the 40 degrees than in the 65 degrees block angle condition for the rear leg. The peak ankle joint moment during the block phase was greater (P < 0.05) in the 40 degrees block angle for the front leg, whereas the peak knee joint moment of the rear leg was greater (P < 0.01) in the 65 degrees block angle condition. The results suggest that the longer initial muscle-tendon lengths of the gastrocnemius and soleus in the block phase at the beginning of force production contribute to the greater peak ankle joint moment and power and consequently the greater block velocity during the sprint start.     

Motorische Leistungsfähigkeit von Kindern und Jugendlichen in Deutschland

Motor performance is an important health resource. Review articles revealed a decline of motor performance of approximately 10?% between 1975 and 2006. In the past most of the data available for such comparisons came from ad hoc studies with non-standardized methods. Within the framework of the ”Motorik-Modul“ (MoMo) study as part of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS), it is possible for the first time to directly compare two cohorts in the ages of 4–17 years in a nationally representative database for Germany. The aim of this article is to report changes in motor performance of children and adolescents in the time period 2003–2006 (cohort baseline n = 4528) compared to 2009–2012 (cohort wave 1, n = 2820). Overall, it is clearly shown that the motor performance of children and adolescents in Germany did not decrease within the observational period of 6 years. The comparison of mean values of the baseline cohort compared to those of wave 1 showed that 28 out of 52 mean values of the two cohorts with a high probability did not differ based on 95?% confidence intervals (CI). In 24 out of the 52 mean values positive changes could be noted based on the individual 95?% CI values. There were more positive changes in primary school aged children than in other age groups. Within these positive changes, most effect sizes were small to medium. The results indicate that recent activities aiming at elevating motor performance levels may have started to make an impact and should be expanded, also in secondary schools. The comparative cohort study presented in this article is currently being checked by the ongoing MoMo wave 2 survey of 2014–2017.