Weight status associations with physical activity intensity and physical self-perceptions in 10-to 11-year-old children

The study examined associations between children&rsquo;s weight status, physical activity intensity, and physical self-perceptions. Data were obtained from 409 children (224 girls) aged 10&ndash;11 years categorized as normal-weight or overweight/obese. Physical activity was assessed using accelerometry, and children completed the Physical Self-Perception Profile. After controlling for the effects of age, maturation, and socioeconomic status vigorous physical activity was significantly associated with normal-weight status among boys (OR = 1.13, p = .01) and girls (OR = 1.13, p = .03). Normal-weight status was significantly associated with perceived Physical Condition (Boys: OR = 5.05, p = .008; Girls: OR = 2.50, p = .08), and Body Attractiveness (Boys: OR = 4.44, p = .007; Girls: OR = 2.56, p = .02). Weight status of 10&ndash;11 year old children was significantly associated with time spent in vigorous physical activity and self-perceptions of Body Attractiveness and Physical Condition.<br /

Biological maturity and primary school children\u27s physical activity : influence of different physical activity assessment instruments

Biological maturation may attenuate hypothesized sex differences in children&rsquo;s physical activity but overall the evidence for this is equivocal. In this study, we investigated how the selection of different physical activity assessment instruments affects the detected relationship between biological maturation and late primary school children&rsquo;s physical activity. Altogether, 175 children (97 girls, 78 boys) aged 10.690.3 years completed the PAQ-C self-report questionnaire and wore ActiGraph GT1M accelerometers for 5 consecutive days. Maturity status was predicted by estimating attainment of age at peak height velocity. Following initial exploration of sex differences in PAQ-C (t-test) and multiple ActiGraph outcome variables (MANOVA), the influence of maturity status was controlled using ANCOVA and MANCOVA. Unadjusted analyses revealed that boys were significantly more active than girls according to the PAQ-C (PB0.0001, d0.52) and ActiGraph (PB0.0001, d0.360.72). After controlling for maturity status, the differences in PAQ-C scores increased (P0.001, d0.64), but the significant differences disappeared for the ActiGraph data (P0.36, d0.170.33). The detected relationship between maturity status and late primary school children&rsquo;s physical activity is dependent on the physical activity assessment tool employed, reflecting the different aspects of physical activity captured by the respective measures.<br /

Fitness, fatness and active school commuting among Liverpool schoolchildren

This study investigated differences in health outcomes between active and passive school commuters, and examined associations between parent perceptions of the neighborhood environment and active school commuting (ASC). One hundred-ninety-four children (107 girls), aged 9–10 years from ten primary schools in Liverpool, England, participated in this cross-sectional study. Measures of stature, body mass, waist circumference and cardiorespiratory fitness (CRF) were taken. School commute mode (active/passive) was self-reported and parents completed the neighborhood environment walkability scale for youth. Fifty-three percent of children commuted to school actively. Schoolchildren who lived in more deprived neighborhoods perceived by parents as being highly connected, unaesthetic and having mixed land-use were more likely to commute to school actively (p < 0.05). These children were at greatest risk of being obese and aerobically unfit(p < 0.01). Our results suggest that deprivation may explain the counterintuitive relationship between obesity, CRF and ASC in Liverpool schoolchildren. These findings encourage researchers and policy makers to be equally mindful of the social determinants of health when advocating behavioral and environmental health interventions. Further research exploring contextual factors to ASC, and examining the concurrent effect of ASC and diet on weight status by deprivation is needed

Adiposity, fitness, health-related quality of life and the reallocation of time between children’s school day activity behaviours: a compositional data analysis

Sedentary time (ST), light (LPA), and moderate-to-vigorous physical activity (MVPA) constitute the range of school day activity behaviours. This study investigated whether the composition of school activity behaviours was associated with health indicators, and the predicted changes in health when time was reallocated between activity behaviours. Accelerometers were worn for 7-days between October and December 2010 by 318 UK children aged 10–11, to provide estimates of school day ST, LPA, and MVPA. BMI z-scores and percent waist-to-height ratio were calculated as indicators of adiposity. Cardiorespiratory fitness (CRF) was assessed using the 20-m shuttle run test. The PedsQL™ questionnaire was completed to assess psychosocial and physical health-related quality of life (HRQL). Log-ratio multiple linear regression models predicted health indicators for the mean school day activity composition, and for new compositions where fixed durations of time were reallocated from one activity behaviour to another, while the remaining behaviours were unchanged. The school day activity composition significantly predicted adiposity and CRF (p = 0.04–0.002), but not HRQL. Replacing MVPA with ST or LPA around the mean activity composition predicted higher adiposity and lower CRF. When ST or LPA were substituted with MVPA, the relationships with adiposity and CRF were asymmetrical with favourable, but smaller predicted changes in adiposity and CRF than when MVPA was replaced. Predicted changes in HRQL were negligible. The school day activity composition significantly predicted adiposity and CRF but not HRQL. Reallocating time from ST and LPA to MVPA is advocated through comprehensive school physical activity promotion approaches. Trial registration: ISRCTN03863885.</p

Accelerometer and self-reported measures of sedentary behaviour and associations with adiposity in UK youth

This study used accelerometer and self-report measures of overall sedentary time (ST) and screen time behaviours to examine their respective associations with adiposity among UK youth. Participants (Year groups 5, 8, and 10; n=292, 148 girls) wore the SenseWear Armband Mini accelerometer for eight days and completed the Youth Activity Profile, an online report tool designed to estimate physical activity and ST.Stature, body mass and waist circumference were measured to classify adiposity outcomes (overweight/obese and central obesity). One-way between groups ANOVA and adjusted linear, logistic and multinomial logistic regression analyses were conducted. There was a significant main effect of age on total ST across the whole week (F(2, 289)=41.64, p≤0.001). ST increased monotonically across Year 5 (581.09±107.81 min·dˉ¹), 8 (671.96±112.59 min·dˉ¹) and 10 (725.80±115.20 min·dˉ¹), and all pairwise comparisons were significant at p≤0.001. A steep age-related gradient to mobile phone use was present (p≤0.001). ST was positively associated with adiposity outcomes independent of moderate-to-vigorous intensity physical activity (MVPA; p≤0.001). Engaging in >3 hours of video gaming daily was positively associated with central obesity (OR=2.12, p≤0.05) but not after adjustment for MVPA. Results further demonstrate the importance of reducing overall ST to maintain healthy weight status among UK youth

Genome-wide analysis of gene expression during Xenopus tropicalis tadpole tail regeneration

BACKGROUND: The molecular mechanisms governing vertebrate appendage regeneration remain poorly understood. Uncovering these mechanisms may lead to novel therapies aimed at alleviating human disfigurement and visible loss of function following injury. Here, we explore tadpole tail regeneration in Xenopus tropicalis, a diploid frog with a sequenced genome. RESULTS: We found that, like the traditionally used Xenopus laevis, the Xenopus tropicalis tadpole has the capacity to regenerate its tail following amputation, including its spinal cord, muscle, and major blood vessels. We examined gene expression using the Xenopus tropicalis Affymetrix genome array during three phases of regeneration, uncovering more than 1,000 genes that are significantly modulated during tail regeneration. Target validation, using RT-qPCR followed by gene ontology (GO) analysis, revealed a dynamic regulation of genes involved in the inflammatory response, intracellular metabolism, and energy regulation. Meta-analyses of the array data and validation by RT-qPCR and in situ hybridization uncovered a subset of genes upregulated during the early and intermediate phases of regeneration that are involved in the generation of NADP/H, suggesting that these pathways may be important for proper tail regeneration. CONCLUSIONS: The Xenopus tropicalis tadpole is a powerful model to elucidate the genetic mechanisms of vertebrate appendage regeneration. We have produced a novel and substantial microarray data set examining gene expression during vertebrate appendage regeneration

Clustered Cardiometabolic Risk, Cardiorespiratory Fitness and Physical Activity in 10-11 Year-Old Children. The CHANGE! Project Baseline

Objectives: The primary objective of this cross sectional pilot study was to report clustered risk scores combining traditional invasive with non invasive cardiometabolic risk markers in 10-11 year old children participating in the CHANGE! project at baseline. A secondary objective was to determine the relationship between clustered risk score and objectively measured physical activity (PA) and cardiorespiratory fitness (CRF). Methods: Habitual PA was measured using accelerometry and CRF (VO2peak) was assessed using an individually calibrated treadmill based protocol. Twenty-nine participants had valid data for all components of the clustered risk score, calculated using total cholesterol: high density lipoprotein-cholesterol (TC:HDL-C), glucose, systolic blood pressure (BP), LV Mass Index (g/m2.7), and trunk fat mass (g). Participants with a clustered risk score greater than 1SD above the mean, were categorised as ‘higher’ risk (n=6); all others were categorised as ‘normal’ risk. \ud \ud Results: Clustered risk score, controlling for somatic maturity and gender, was negatively correlated with VPA (r= -0.51, p=0.01), MVPA (r= -0.44, p=0.03) and VO2peak (r= -0.57, p<0.01). ANCOVA, with somatic maturity and gender as covariates, revealed that those in the ‘normal’ risk group were more fit than those in the ‘higher’ risk group [f (1,24)=4.518, p=0.044]). There were no statistically significant differences between risk groups and PA however mean data suggest that those in the ‘normal’ risk group accrued 4 minutes more daily VPA than the ‘higher’ risk group which may be clinically important. \ud \ud Conclusions: This provides further evidence of the importance of promoting CRF and VPA in children, to reduce cardiometabolic risk especially for those that are ‘higher’ risk