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Longitudinal study of the associations between change in sedentary behavior and change in adiposity during childhood and adolescence: Gateshead Millennium Study
Background:
Sedentary time (ST) has been reported to have a range of negative health effects in adults, however, the evidence for such effects among children and adolescents is sparse. The primary aim of the study was to examine associations between changes in sedentary behavior (time and fragmentation) and changes in adiposity across childhood and adolescence.
Methods:
Participants were recruited as part of the Gateshead Millennium Study. Measures were taken at age 7 (
n
=502), 9 (
n
=506), 12 (
n
=420) and 15 years (
n
=306). Participants wore an ActiGraph GT1M and accelerometer epochs were ‘sedentary’ when recorded counts were ⩽25 counts per 15 s. ST was calculated and fragmentation (SF) was assessed by calculating the number of sedentary bouts per sedentary hour. Associations of changes in ST and SF with changes in adiposity (body mass index (BMI), and fat mass index (FMI)) were examined using bivariate linear spline models.
Results:
Increasing ST by 1% per year was associated with an increase in BMI of 0.08 kg m
−2
per year (95% CI: 0.06–0.10;
P
<0.001) and FMI of 0.15 kg m
−2
per year (0.11–0.19;
P
<0.001). Change in SF was associated with BMI and FMI (
P
<0.001). An increase of 1 bout per sedentary hour per year (that is, sedentary time becoming more fragmented) was associated with an increase in BMI of 0.07 kg m
−2
per year (0.06–0.09;
P
<0.001) and an increase in FMI of 0.14 kg m
−2
per year (0.10–0.18;
P
<0.001) over the 8 years period. However, an increase in SF between 9–12 years was associated with a 0.09 kg m
−2
per year decrease in BMI (−0.18–0.00;
P
=0.046) and 0.11 kg m
−2
per year decrease in FMI (−0.22–0.00;
P
=0.049).
Conclusions:
Increased ST and increased SF from 7–15 years were associated with increased adiposity. This is the first study to show age-specific associations between change in objectively measured sedentary behavior and adiposity after adjustment of moderate-to-vigorous-intensity physical activity in children and adolescents. The study suggests that, targeting sedentary behavior for obesity prevention may be most effective during periods in which we see large increases in ST.
Journal Article
Mothers' perceptions of child weight status and the subsequent weight gain of their children: a population-based longitudinal study
Background:
There is a plethora of cross-sectional work on maternal perceptions of child weight status showing that mothers typically do not classify their overweight child as being overweight according to commonly used clinical criteria. Awareness of overweight in their child is regarded as an important prerequisite for mothers to initiate appropriate action. The gap in the literature is determining whether, if mothers do classify their overweight child’s weight status correctly, this is associated with a positive outcome for the child’s body mass index (BMI) at a later stage.
Objective:
To explore longitudinal perceptions of child weight status from mothers of a contemporary population-based birth cohort (Gateshead Millennium Study) and relationships of these perceptions with future child weight gain.
Methods:
Data collected in the same cohort at 7, 12 and 15 years of age: mothers’ responses to two items concerning their child’s body size; child’s and mother’s BMI; pubertal maturation; demographic information.
Results:
Mothers’ perceptions of whether their child was overweight did not change markedly over time. Child BMI was the only significant predictor of mothers’ classification of overweight status, and it was only at the extreme end of the overweight range and in the obese range that mothers reliably described their child as overweight. Even when mothers did appropriately classify their child as overweight at an earlier stage, this was not related to relatively lower child BMI a few years later.
Conclusions:
Mothers tend to classify their child as overweight in only more extreme cases. It is an important finding that no beneficial impact was shown on later child BMI in overweight children whose mothers classified their child’s weight status as overweight at an earlier stage.
Journal Article
Tracking of sugar-sweetened soft drinks and other common beverages from infancy to childhood and adolescence
The beverage data were sorted into six categories (soft drinks (non-diet carbonated), fruit juice, squash, diet soft drinks (carbonated and non-carbonated), milk and water). Associations between high beverage intake at 30 months and high intake at 7 and 15 years were tested using logistic regression, adjusting for potentially confounding factors (gender and a binary measure of socio-economic status (SES) assessed at recruitment in 1999(7)).The reference value for adjusted Odds Ratios (aOR) was low or no intake. The adjusted odds ratio for being a soft drink consumer at age 7 years was almost 3 times the reference value of a non-consumer at age 30 months, but when the analysis was stratified for SES this increased to almost 5 times the reference for those of higher SES (OR 4.87 95% CI 2.34–10.14 P < 0.001) compared to those of lower SES where the OR was not significant. 7 years 15 years Beverage intake at 30 months aOR 95% CI P-value aOR 95% CI P-value Soft Drinks Consumer 2.912 1.652,5.135 <0.001 1.778 0.848,3.726 0.128 Squash High Intake 1.443 0.754,2.759 0.268 1.613 0.768,3.384 0.206 Fruit Juice High Intake 3.624 1.958,6.708 <0.001 1.640 0.761,3.533 0.207 Dist Soft Drinks Consumer 4.520 2.289,8.926 <0.001 2.091 0.961,4.551 0.063 Water High Intake 2.954 1.610,5.420 <0.001 1.410 0.631,3.151 0.402 Milk High Intake 1.988 0.993,3.980 0.053 0.991 0.452,2.170 0.982 These data suggest that the family environment can protect toddlers and children from excessive exposure to sweetened beverages, but that by adolescence young people are more exposed to external influences. 1.
Journal Article
Measurement of exclusive$${\\varvec{{{{\\pi ^+\\pi ^-}}}}}$$π + π - and$${\\varvec{{{{\\rho ^0}}}}}$$ρ 0 meson photoproduction at HERA
Abstract Exclusive photoproduction ofρ ⁰ (770)ρ 0 ( 770 ) mesons is studied using the H1 detector at the ep collider HERA. A sample of about 900,000 events is used to measure single- and double-differential cross sections for the reactionγ p → π ⁺π ⁻Yγ p → π + π - Y . Reactions where the proton stays intact (m_(Y) =m_(p)m Y = m p ) are statistically separated from those where the proton dissociates to a low-mass hadronic system (m_(p)
Journal Article
Relationships between standing and stepping time and executive functions in children aged 3–5 years
Introduction: Physical activity improves cognitive abilities, particularly higher order executive functions, in school-aged children. There was a significant difference between working memory capacity groups in the proportion of time spent stepping, F(4, 186)=3.55, p=.008, η2=.07; Those children who scored in the lowest working memory group spent significantly more time stepping...
Journal Article
Sitting time among young children in childcare: Differences by sex, age, weight status and socio-economic status
Introduction: Excessive time spent sitting, independent of the amount of moderate- to vigorous-intensity physical activity (MVPA) undertaken, is negatively associated with measures of adiposity, cardio-metabolic health, and psychosocial health in adults and adolescents. The purpose of this study was to describe sitting time during childcare in children aged 1-5 years,...
Journal Article
Validation of the Sensewear Mini activity monitor in 6–12 year old children
Methods: Twenty-six children (10.1±1.6 years, 61.5% boys) completed a protocol involving 15 semi-structured sedentary (resting, TV viewing, handheld computer game, computer game and writing), light (slow walk, getting ready in the morning, standing classroom activities and chores), and moderate-to-vigorous (brisk walk, dancing, basketball, soccer, running and obstacle course) intensity activities...
Journal Article
Promoting physical activity among adolescent girls: the Girls in Sport group randomized trial
Background
Slowing the decline in participation in physical activity among adolescent girls is a public health priority. This study reports the outcomes from a multi-component school-based intervention (
Girls in Sport
), focused on promoting physical activity among adolescent girls.
Methods
Group randomized controlled trial in 24 secondary schools (12 intervention and 12 control). Assessments were conducted at baseline (2009) and at 18 months post-baseline (2010). The setting was secondary schools in urban, regional and rural areas of New South Wales, Australia. All girls in Grade 8 in 2009 who attended these schools were invited to participate in the study (
N
= 1769). Using a Health Promoting Schools and Action Learning Frameworks, each school formed a committee and developed an action plan for promoting physical activity among Grade 8 girls. The action plan incorporated strategies in three main areas – i) the formal curriculum, ii) school environment, and iii) home/school/community links – based on the results of formative data from target girls and staff and on individual needs of the school. A member of the research team supported each school throughout the intervention. The main outcome measure was accelerometer-derived total physical activity (TPA) spent in physical activity. Data were analyzed from December 2011 to March 2012.
Results
1518 girls (mean age 13.6y ±0.02) were assessed at baseline. There was a significant decline in TPA from baseline to 18-month follow-up with no differences between girls in the intervention and control schools. Only one-third of schools (4/12) implemented the intervention as per their action plan. Per-protocol analyses on these schools revealed a smaller decline in percentage of time spent in MVPA among girls in the intervention group (adjusted difference 0.5%, 95% CI = -0.01, 0.99,
P
= 0.05).
Conclusions
The
Girls in Sport
intervention was not effective in reducing the decline in physical activity among adolescent girls. Lack of implementation by most intervention schools was the main reason for a null effect. Identifying strategies to enhance implementation levels is critical to determining the true potential of this intervention approach.
Trial registration
This study was retrospectively registered with the Australian New Zealand Clinical Trials Registry
ACTRN12610001077055
.
Date of registration: 7 December 2010.
Journal Article