45 research outputs found
Impact of school outdoor environment upon pupils' physical activity and sun exposure across ages and seasons
Background and aims: Among children, the lack of physical activity (PA) is widespread in
developed countries. Further, the majority of all skin cancers depend on an overexposure to solar
ultraviolet radiation (UVR) in early life. The combination of sufficient PA and suberythemal UVR
exposure (potentially sufficient for vitamin D production) dispersed over the day is vital to general
wellbeing and bone health, especially in growing children and adolescents. However, long regulated
school days entail less free mobility and outdoor stay, which may jeopardize the opportunities for
cohesive intense physical activity (PA) and suberythemal UVR exposure. The impact of the school
outdoor environment upon schoolchildren’s PA has been studied but not in combination with the
exposure to UVR from the sun during the school day in children of different ages during one
academic year containing different seasons. The overall aim for this thesis was to examine the crosssectional
impact of outdoor environments at compulsory school level in different seasons upon PA
and solar UVR exposure in Swedish pupils.
Material and Methods: The impact of school outdoor environment upon pupils' physical activity and
UVR exposure during free-mobility, scheduled time and physical education (PE) were studied in 196
pupils aged 7-15 years (grades 2, 5, and 8) at four schools in mid-southern Sweden during 5
consecutive days each in September, March and May. Actigraph GT3X+ Activity monitors were used
for PA assessments and for separation of indoor from outdoor stay, supplementary to ocular
observation. Predictors for PA during school stay, expressed as mean daily accelerometer counts and
time in different PA intensities were measured per season, day, grade and gender. For individual
assessment of erythemally effective UVR (joule per exposed m2 of the skin), a polysulphone film
dosimeter badge was pinned to the top of the pupils’ right shoulders and worn during school-time
during the entire week. Their individual UVR exposures were related to and expressed as fractions of
total available ambient UVR in the schools’ outdoor environments which differed considering amount
of shade, vegetation, and peripheral city-scape quantified as percentage of free sky view calculated by
fish-eye photography. Questionnaires and diaries were applied to control for confounders.
Results: Overall, free-living PA outdoors generated the highest mean accelerometer counts for
moderate and vigorous physical activity (MVPA), and together with outdoor physical education
contributed with 50% of total mean accelerometer counts though representing only 25% of the total
school time. Season, age, gender and weather had an impact on both PA and UVR exposure, with less
PA and UVR exposure. In March, in inclement weather both PA and UVR exposure dropped,
especially among older pupils and girls. During all seasons both MVPA counts and UVR exposures
were significantly higher among 2nd graders vs. 5th and 8th graders. In September and March play at
sport fields had a positive impact on pupils’ PA and suberythemal sun exposure (potentially sufficient
for vitamin D production). Among 2nd and 5th graders and in September this interaction between
attributes of the physical environment and level of PA and UVR exposure was pronounced. In May
overexposure to UVR did occur, though green settings with trees and shrubs and fixed play equipment
close to the greenery protected from hazardous UV exposure and promoted high levels of MVPA.
Conclusions: More time outdoors, at all seasons, would favorably increase school children´s chances
of reaching recommended levels of PA. There is a potential for prolonged suberythemal outdoor stay
for play in open areas during fall and early spring at Lat.56oN. Outdoor activities in such settings
should therefore be encouraged. In late spring, long outdoor exposures of the youngest pupils warrant
UVR-protective outdoor environment. Access to vegetation and/or shaded structures (e.g. trees,
bushes, roofs) attractive for play should be provided for
Verifying the Kugo-Ojima Confinement Criterion in Landau Gauge Yang-Mills Theory
Expanding the Landau gauge gluon and ghost two-point functions in a power
series we investigate their infrared behavior. The corresponding powers are
constrained through the ghost Dyson-Schwinger equation by exploiting
multiplicative renormalizability. Without recourse to any specific truncation
we demonstrate that the infrared powers of the gluon and ghost propagators are
uniquely related to each other. Constraints for these powers are derived, and
the resulting infrared enhancement of the ghost propagator signals that the
Kugo-Ojima confinement criterion is fulfilled in Landau gauge Yang-Mills
theory.Comment: 4 pages, no figures; version to be published in Physical Review
Letter
Energy-momentum tensor form factors of the nucleon in nuclear matter
The nucleon form factors of the energy-momentum tensor are studied in nuclear
medium in the framework of the in-medium modified Skyrme model. We obtain a
negative D-term, in agreement with results from other approaches, and find that
medium effects make the value of d_1 more negative.Comment: 9 pages, 11 figures. Some typos were removed and one reference was
adde
Evaluation der bundesweiten Inanspruchnahme und Umsetzung der Leistungen fĂĽr Bildung und Teilhabe: erster Zwischenbericht
A repeated measurement study investigating the impact of school outdoor environment upon physical activity across ages and seasons in Swedish second, fifth and eighth graders
Compulsory School In- and Outdoors—Implications for School Children’s Physical Activity and Health during One Academic Year
Regulated school days entail less free-living physical activity (PA) and outdoor stay, which may jeopardize the opportunities for cohesive moderate-to-vigorous physical activity (MVPA) and, by extension, children’s health. The role of outdoor stay during school time for pupils’ free-living PA vs. physical education (PE) and indoor stay was studied during one academic year in 196 pupils aged 7–14 years at four schools in mid-southern Sweden during five consecutive days each in September, March, and May. Actigraph GT3X+ Activity monitors were used. Predictors for PA during school stay were expressed as mean daily accelerometer counts and were measured per season, day, grade, gender, weather, and time outdoors. Overall, free-living PA outdoors generated the highest mean accelerometer counts for moderate and vigorous PA. Outdoor PA and PE, representing 23.7% of the total school time contributed to 50.4% of total mean accelerometer counts, and were the greatest contributors to moderate and vigorous PA. Age and weather impacted PA, with less PA in inclement weather and among older pupils. More time outdoors, at all seasons, would favorably increase school children’s chances of reaching recommended levels of PA
Att studera förskolebarns fysiska aktivitet
Förskolebarns fysiska aktivitet har en viktig hälsopromotiv effekt mot flera av våra välfärdssjukdomar. Därför är det av yttersta vikt att förskolemiljön stimulerar förskolebarnen till en hälsosam fysisk aktivitet. I Kidscape projektet studerade vi förskolebarns fysiska aktivitet under vistelsen på förskolan. Syftet var att hitta faktorer i skolgårdens utemiljö som påverkar barnens aktivitetsmönster. Aktivitetsmönstret studerades med både subjektiva (CARS och kvalitativ observation) och objektiva metoder (pedometri och accelerometri). Resultatet visade att förskolebarnens fysiska aktivitet var högre i förskolor med en bra skolgårdsmiljö. Slutsats: förskole gårdens utformning kan främja en hälsosam fysisk aktivitet hos förskolebarn
The study of children’s physical activity
Preschool children's physical activity has an important health promoter against several of the lifestyle diseases. Therefore it is important that the preschool environment encourages preschool children to a healthy physical activity. In the Kidscape project we studied preschool children's physical activity during their stay at the preschool. The aim was to identify factors in the outdoor environment that influence children's activity patterns. Activation patterns were studied with both subjective methods (CARS and qualitative observation) and objective methods (pedometri and accelerometry). The results showed that preschool children's physical activity was higher in preschools with a good schoolyard environment. Conclusion: preschool outdoor environment can promote a healthy physical activity in preschool children