Comparison of two Actigraph models for assessing free-living physical activity in Indian adolescents

This aim of this study was to compare the new Actigraph (GT1M) with the widely used Model 7164. Seven days of free-living physical activity were measured simultaneously using both the Model 7164 and GT1M in 30 Indian adolescents (mean age 15.8 years, s = 0.6). The GT1M was on average 9% lower per epoch than model 7164, thus a correction factor of 0.91 is suggested for comparison between the two monitors. The differences between monitors increased in magnitude with intensity of activity (P < 0.001) but remained randomly distributed (r = 0.01, P = 0.96). No significant difference was observed between monitors for time spent in moderate (P = 0.31) and vigorous (P = 0.34) physical activity when using the same epoch length. The Model 7164 classified less time as sedentary (P < 0.001) and more time as light-intensity activity (P < 0.001) than the GT1M. In conclusion, data from the GT1M can be compared with historical data using average counts per minute with a correction factor, and the two models might be comparable for assessing time spent in moderate to vigorous physical activity in children when using the same epoch length.     

Hot and Cool Self-Regulation,Academic Competence,and Maladjustment: Mediating and Differential Relations

This study examined differential and mediating relations between hot and cool self-regulation (M_age = 48.2 months; N = 1,155, 48% girls), first-grade (M_age = 77.5 months) maladjustment (externalizing [EXT] and internalizing [INT] behavior), and first- and second-grade (M_age = 89.5 months) academic competence (AC). Using teacher reported EXT, INT, and AC, partial support for the differential perspective was found in that only hot self-regulation was significantly related to EXT, whereas both hot and cool self-regulation was significantly related to AC. Moreover, hot self-regulation indirectly predicted second-grade AC through first-grade EXT, lending some support for the mediating perspective also. The findings contribute to an understanding of how self-regulation is related to academic and behavioral school adjustment.     

Associations between individual and collective efficacy beliefs and students' bystander behavior

This study examined whether defending and passive bystanding during peer victimization episodes were associated with individual- and classroom-level efficacy to stop peer victimization. Self-report survey data were analyzed from 1,467 Swedish fourth-grade students (mean age = 10.55) from 100 classrooms in 63 schools. Multilevel analyses revealed that, when witnessing peer victimization, students more often defended victims if they were high in defender self-efficacy and if they belonged to classrooms high in collective efficacy. In contrast, students were more likely to remain passive if they were low in defender self-efficacy and if they belonged to classrooms low in collective efficacy. Taken together, our findings suggest that efficacy beliefs both at the individual and at the classroom level contribute to explaining variability in students' bystander behaviors, which has potential implications for prevention and intervention work.     

Elite football on artificial turf versus natural grass: movement patterns, technical standards, and player impressions

The aim of the present study was to examine the movement patterns, ball skills, and the impressions of Swedish elite football players during competitive games on artificial turf and natural grass. Time - motion analyses (36 observations) and technical analyses (16 team observations) were performed and 72 male and 21 female players completed a questionnaire. No differences were observed between artificial turf and natural grass in terms of total distance covered (mean 10.19 km, s = 0.19 vs. 10.33 km, s = 0.23), high-intensity running (1.86 km, s = 0.10 vs. 1.87 km, s = 0.14), number of sprints (21, s = 1 vs. 22, s = 2), standing tackles (10, s = 1 vs. 11, s = 1) or headers per game (8, s = 1 vs. 8, s = 1), whereas there were fewer sliding tackles (P < 0.05) on artificial turf than natural grass (2.1, s = 0.5 vs. 4.3, s = 0.6). There were more short passes (218, s = 14 vs. 167, s = 12) and midfield-to-midfield passes (148, s = 11 vs. 107, s = 8) (both P < 0.05) on artificial turf than natural grass. On a scale of 0-10, where 0 = "better than", 5 = "equal to", and 10 = "worse than", the male players reported a negative overall impression (8.3, s = 0.2), poorer ball control (7.3, s = 0.3), and greater physical effort (7.2, s = 0.2) on artificial turf than natural grass. In conclusion, the running activities and technical standard were similar during games on artificial turf and natural grass. However, fewer sliding tackles and more short passes were performed during games on artificial turf. The observed change in playing style could partly explain the male players' negative impression of artificial turf.     

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.     

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.

     

Functional reading difficulties in Denmark

In this first Danish study of adult reading skills, 1124 adults between 18 and 67 years of age participated in an interview about reading habits and skills, and 445 were tested individually at home using six common texts. Great care was taken to ascertain that subjects were representative of the whole adult population and that the texts covered most types of everyday reading. Three percent of the participants were found to have severe functional reading difficulties and a further 9 percent to have moderate difficulties. Regression analyses found several unique predictors of reading difficulties: age (adults over 45 years reading more poorly than younger adults), limited basic education, no vocational training nor higher education, and a small amount of reading needed at work. The rate of poor readers was about four times higher among persons with low income than among others. Men and women read equally well although men tended to rate themselves lower as readers than women did. Methodological issues and some educational implications are discussed.     

‘Children’s clans’; social organisation and interpretive reconstruction as aspects on development of peer-groups in outdoor play

The focus of this article is children’s self-organisation of peer-groups through play. The play was initiated by encounters with the environment. The use of ethnographic methods in early childhood research has proved helpful to elucidate, interpret, and understand children’s experiences and the creation of meaning in their everyday lives. This inquiry draws on field notes, informal conversations with the children, and photos from a study of kindergarten children’s experiences of outdoor places and landscapes in Norway. Going out of doors together with the children regularly over a period of 10 months revealed aspects of how children’s interactions in play connect to their use of natural landscapes and its place in peer-group social organisation. The data are presented as ‘narrative maps’ and episodes written as ‘emplotted’ narratives.