Physical activity, cardiorespiratory fitness, and clustered cardiometabolic risk in 10- to 12-year-old school children: the REACH Y6 study

Visualization analysis of research progress for walkability

The study of walkability is of great significance to the construction of healthy cities. In this paper, taking 1283 articles of walkability, which were included in Web of Science, as the research object. This paper adopts to analysis the research progress by using the method of scientometrics and knowledge networks analysis. Objectively and systematically analyze the research progress of walkability abroad from the aspects of publication overview, knowledge foundation, research direction and hot spots, etc. It is found that foreign researches on walkability mainly include three core directions: walkability and physical activity, walkability evaluation, walkability and urban design. Among them, walkability and physical activity orientation have been studied from various perspectives, such as various groups, various environmental types, different behavioral patterns and various chronic diseases. With the increasingly prominent urbanization problems and the rapid development of new technologies, multiple data, new methods and interdisciplinary cooperation will actively promote the vigorous development of walking suitability research.

Cardiorespiratory Fitness Growth in Middle School: Socio-Demographic Factor Associations

Purpose: The purposes of this study were to (a) examine the three-year longitudinal growth trends of cardiorespiratory fitness among middle school students, and (b) examine the associations between individual and school-level socio-demographic variables and middle school student cardiorespiratory fitness performance. Methods: A longitudinal multilevel analysis design was used. Participants were adolescents (N = 44,801; 48.1% girls) from 33 middle schools in an Eastern U.S. state. The grand mean age for the participants was 12.42 ± 0.98 years old. Individual-level variables included grade (testing year), sex, and the 15-m Progressive Aerobic Cardiovascular Endurance Run (PACER) performance, which was measured annually for 3 years. School-level variables included the percentage of students receiving a free and reduced-price meal, student-faculty ratio for physical education, and school-level academic performance. Results: A three-level hierarchical linear model was used to model the longitudinal performance change across 3 years accounting for individual and school-level factors. A quadratic growth curve was identified in PACER performance changes, with a positive first-order coefficient (β = 3.05) and a negative second-order coefficient (β =-0.82) overall. Sex was significantly associated with PACER changes (p < .01), with boys and girls having divergent longitudinal growth curves. School-level academic performance was positively associated with PACER performance; however, the association was not statistically significant. Conclusion: Results indicate that although cardiorespiratory fitness improved across years, on average, performance did not keep up with healthy fitness zone recommendations. In addition, sex-based discrepancies were evident as boys and girls demonstrated different quadratic growth curves in cardiorespiratory fitness.

Prospective physical fitness status and development of cardiometabolic risk in children according to body fat and lifestyle behaviours: The IDEFICS study

BACKGROUND

Elevated cardiometabolic risk (CMR) is an important factor for cardiovascular diseases later in life while physical fitness seems to decrease CMR.

OBJECTIVE

Thus, the aim of the present study is to assess the association between muscular fitness (MF) and cardiorespiratory fitness (CRF) on CMR in European children, both cross-sectional and longitudinally.

METHODS

A total of 289 children (49.5% males) from eight European countries, aged 6 to 9, with longitudinal information on blood pressure, triglycerides, total cholesterol, HDL-cholesterol, homoeostasis model assessment, body mass index, data on fitness level, objectively measured physical activity (PA), diet quality, and total screen time were included. A CMR score was calculated and dichotomized. MF and CRF were also dichotomized. Cross-sectional and longitudinal multilevel logistic regressions adjusting for lifestyle behaviours were performed.

RESULTS

Reaching a high level of MF during childhood as well as remaining in that level over-time were associated with an 82% and 62% lower probability of high CMR at follow-up, respectively. Also, children who became top CRF over time, showed a 77% lower probability (P < 0.05) of being in the highest CMR quartile at follow-up, independently of sociodemographic and lifestyle indicators.

CONCLUSIONS

A high MF at early childhood and during childhood reduces the odds of having CMR. Same occurs with the improvement of CRF during childhood. These findings highlight the importance of enhancing fitness to avoid CMR already in children.

Associations between Second-Hand Tobacco Smoke Exposure and Cardiorespiratory Fitness, Physical Activity, and Respiratory Health in Children

BACKGROUND

Cardiorespiratory fitness (CRF) and physical activity (PA) are associated with a plethora of positive health effects. Many UK children fail to meet the recommended level of PA, with an observed decline in CRF levels over recent decades. Second-hand tobacco smoke (SHS) is responsible for a significant proportion of the worldwide burden of disease, but little is understood regarding the impact of SHS exposure on CRF and PA in children. The aim of this study was to test the associations between SHS exposure and CRF, PA, and respiratory health in children.

METHOD

Children (9-11 years) from UK primary schools in deprived areas participated (n = 104, 38 smoking households). Surveys determined household smoking, and exhaled carbon monoxide was used to indicate children's recent SHS exposure. CRF (VO_2peak) was assessed via maximal treadmill protocol using breath-by-breath analysis. Fractional exhaled nitric oxide and spirometry were utilised as indicators of respiratory health.

RESULTS

Linear regression models demonstrated that SHS exposure was negatively associated with allometrically scaled VO_2peak (B = -3.8, p = 0.030) but not PA or respiratory health.

CONCLUSION

The results indicate that SHS is detrimental to children's CRF; given that approximately one-third of children are regularly exposed to SHS, this important finding has implications for both public health and the sport and exercise sciences.

PROMIS Paediatric Mobility tool is correlated with accelerometer-measured physical activity in children with hip diseases

AIMS

The reduction in mobility due to hip diseases in children is likely to affect their physical activity (PA) levels. Physical inactivity negatively influences quality of life and health. Our aim was to objectively measure PA in children with hip disease, and correlate it with the Patient-Reported Outcomes Measurement Information System (PROMIS) Mobility Score.

METHODS

A total of 28 children (12 boys and 16 girls) with hip disease aged between 8and 17 years (mean 12 (SD 3)) were studied between December 2018 and July 2019. Children completed the PROMIS Paediatric Item Bank v. 2.0 - Mobility Short Form 8a and wore a hip accelerometer (ActiGraph) for seven consecutive days. Sedentary time (ST), light PA (LPA), moderate to vigorous PA (MVPA), and vigorous PA were calculated from the accelerometers' data. The PROMIS Mobility score was classified as normal, mild, and moderate functions, based on the PROMIS cut scores on the physical function metric. A one-way analysis of covariance (ANCOVA) was used to assess differences among mobility (normal; mild; moderate) and measured PA and relationships between these variables were assessed using bivariate Pearson correlations.

RESULTS

Children classified as normally functioning on the PROMIS had less ST (p = 0.002), higher MVPA, (p = 0.002) and VPA (p = 0.004) compared to those classified as mild or moderate function. A moderate correlation was evident between the overall PROMIS score and daily LPA (r = 0.462, n = 28; p = 0.013), moderate-to-vigorous PA (r = 0.689, n = 28; p = 0.013) and vigorous PA (VPA) (r = 0.535, n = 28; p = 0.013). No correlation was evident between the mean daily ST and overall PROMIS score (r = -0.282, n = 28; p = 0.146).

CONCLUSION

PROMIS Pediatric Mobility tool correlates well with experimentally measured levels of physical activity in children with hip disease. We provide external validity for the use of this tool as a measure of physical activity in children. Cite this article: Bone Joint J 2021;103-B(2):405-410.

Impact of sedentary behavior on large artery structure and function in children and adolescents: a systematic review

Sedentary behavior contributes to increased atherosclerotic risk in adults. Whether or not this can be extended to pediatric populations is unclear. This systematic review assessed associations of sedentary behavior with large artery structure and function in pediatric populations. MEDLINE, EMBASE, CENTRAL, and Web of Science were searched from the earliest available date to 31st of December 2018. Analyses of associations of sedentary behavior with large artery structure or function in a pediatric (sub-)population were included, adhering to the PRISMA guidelines. The protocol was published in advance on PROSPERO (CRD42018112996). Study quality and quality of evidence were analyzed using NHLBI Study Quality assessment tools and GRADE. Six observational studies found no association of exposure and outcome variables, and one had contradicting results. One intervention found reduced flow-mediated dilation after 3 h of uninterrupted sitting. Exposure and outcome measures were highly heterogeneous. Study quality was low to moderate. Quality of evidence was very low or low in the observational studies and high in the intervention.Conclusion: In pediatric populations, current evidence is limited and of low quality about how acute effects of sedentary behavior translate into early vascular aging and the long-term development of vascular dysfunction and atherosclerotic risk. Future studies should emphasize a careful choice of the adequate type and measurement site of a biomarker for large artery structure and function as well as conduct a detailed assessment of sedentary behavior patterns.Trial registration: PROSPERO Registration Number: CRD42018112996What is known: • An independent association of sedentary behavior and biomarkers of large artery structure and function has been demonstrated in adults. • In children, sedentary behavior is directly associated with classical cardiovascular risk factors like elevated blood glucose levels, insulin resistance, high blood pressure, obesity, and elevated blood lipids.What is new: • Currently, only few studies of low quality in children and adolescents provide limited evidence about how acute effects of sedentary behavior translate into early vascular aging and the long-term development of atherosclerosis. • The type and measurement site of vascular biomarker need to be chosen carefully, and a detailed assessment of sedentary behavior patterns is important to minimize the methodological bias.

Physical activity maintenance and metabolic risk in adolescents

Aim

Examine the association between child and adolescent physical activity maintenance categories and metabolic profile in adolescence.

Methods

This cross-sectional study was conducted with 1152 adolescents (57.4% female) aged 10-16 years from Londrina, Brazil. Physical activity was self-reported in childhood (7-10 years old, retrospective data) and adolescence through questionnaires. Cardiorespiratory fitness (20 m shuttle-run test), body fat (skinfolds), waist circumference, blood pressure (automatic instrument) and blood variables (fasting glucose, HDL-cholesterol and triglycerides) were measured at adolescence.

Results

Frequency of physical activity in childhood and adolescence was 50.3 and 17.2%, respectively, and only 25.7% of boys and 10.9% of girls were active at both ages. Adolescents who were physically active in childhood alone were less likely [OR = 0.71 (95% CI: 0.52-0.97)] to present low cardiorespiratory fitness in adolescence compared to those who were non-active in childhood. Regardless of controlled, actives in childhood and adolescence were less likely to present low cardiorespiratory fitness [OR = 0.50 (95% CI: 0.34-0.73)], high blood pressure [OR = 0.52 (95% CI: 0.32-0.85)] and high metabolic risk score [OR = 0.44 (95% CI: 0.22-0.90)] compared to the non-actives at both ages.

Conclusions

Actives through childhood to adolescence are less likely to present low cardiorespiratory fitness, high blood pressure and high metabolic risk.

A Pedometer-Based Physically Active Learning Intervention: The Importance of Using Preintervention Physical Activity Categories to Assess Effectiveness

PURPOSE

To assess physical activity outcomes of a pedometer-based physically active learning (PAL) intervention in primary school children.

METHODS

Six paired schools were randomly allocated to either a 6-week teacher-led pedometer-based physically active learning intervention or a control (n = 154, female = 60%, age = 9.9 [0.3] y). Accelerometers assessed total daily sedentary time, light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA). Preintervention mean daily MVPA minutes grouped participants as Low Active (<45 min/d) and High Active (≥45 min/d).

RESULTS

From the final sample size, the intervention (n = 52) significantly improved LPA versus control (n = 31, P = .04), by reducing sedentary time. More intervention (+10%) than control (+3%) pupils met the 60 minutes per day guidelines. In both intervention subgroups, pupils spent less time in LPA (P < .05) versus control. The greatest nonsignificant increase was found in the Low Active pupils MVPA levels.

CONCLUSIONS

Improvements in LPA were statistically significant in the intervention versus control group. In subgroup analysis, Low Active pupils in the intervention showed the greatest beneficial effects and the Most Active pupils may have replaced MVPA and sedentary time with LPA. The intervention group housed clusters of pupils showing variable responsiveness, justifying routine examination of subgroup variability in future studies.

Cross-sectional associations between body mass index and social-emotional wellbeing among differentially active children

BACKGROUND

This study assessed gender-specific associations between body mass index (BMI) and social-emotional wellbeing (SEW) among differentially active seven-year-old children.

METHODS

Data are from wave four of the UK Millennium Cohort Study, collected in 2007-08. Children wore an ActiGraph accelerometer for seven consecutive days and measures of stature and body mass were taken. BMI was calculated from stature and body mass (kg/m2). Parents/carers completed the strengths and difficulties questionnaire (SDQ). A total of 6011 children (3073 girls) had completed data. Mean minutes per day spent in moderate-to-vigorous intensity physical activity (MVPA) were calculated for each child. Gender-specific MVPA quartile cut-off values categorized boys and girls separately into four graded groups representing the least (Q1) through to the most active (Q4) children. Adjusted linear regression analyses examined associations between BMI and SDQ scores. Gender-specific analyses were conducted separately for MVPA quartiles.

RESULTS

BMI was positively associated with peer problems for Q1 and Q2 boys and girls, conduct problems for Q2 and Q4 boys, emotional problems and prosocial behaviour for Q2 boys and total difficulty scores for Q1 girls and Q2 boys (P < 0.05).

CONCLUSIONS

Our results revealed that BMI was positively associated with SEW difficulties among the low active children but not the high active children. Further research examining the concurrent effect of diet and MVPA on child weight status and SEW is needed.

Cardiometabolic risk through an integrative classification combining physical activity and sedentary behavior in European adolescents: HELENA study

PURPOSE

This study aims to compare adolescents' cardiometabolic risk score through an integrative classification of physical activity (PA), which involves the combination of moderate-to-vigorous physical activity (MVPA) and sedentary behavior (SB).

METHODS

A cross-sectional study derived from the Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study database (2006-2008) was conducted in adolescents (n = 548; boys, 47.3%; 14.7 ± 1.2 years) from 10 European cities. MVPA and SB were objectively measured using accelerometry. Adolescents were divided into 4 categories according to MVPA (meeting or not meeting the international recommendations) and the median of SB time (above or below sex- and age-specific median) as follows: High-SB & Inactive, Low-SB & Inactive, High-SB & Active, and Low-SB & Active. A clustered cardiometabolic risk score was computed using the homeostatic model assessment, systolic blood pressure, triglycerides, total cholesterol/high-density lipoprotein cholesterol, sum 4 skinfolds, and cardiorespiratory fitness (CRF). Analyses of covariance were performed to discern differences on cardiometabolic risk scores among PA categories and each health component.

RESULTS

The cardiometabolic risk score was lower in adolescents meeting the MVPA recommendation and with less time spent in SB in comparison to the high-SB & Inactive group (p < 0.05). However, no difference in cardiometabolic risk score was established between High-SB or Low-SB groups in inactive adolescents. It is important to note that CRF was the only variable that showed a significant modification (higher) when children were compared from the category of physically inactive with "active" but not from high- to low-SB.

CONCLUSION

Being physically active is the most significant and protective outcome in adolescents to reduce cardiometabolic risk. Lower SB does not exhibit a significant and extra beneficial difference.

Moderators of School-Based Physical Activity Interventions on Cardiorespiratory Endurance in Primary School-Aged Children: A Meta-Regression

The purpose of this study was to examine potential moderators of school-based physical activity interventions on cardiorespiratory endurance in primary school-aged children using meta-regression. An Internet search with several databases was employed, extracting school-based pediatric physical activity intervention studies published within the past 30 years. Studies were included if there was a control or comparison group, if the study sample included primary school-aged children, if the targeted outcome of cardiorespiratory endurance was objectively assessed, if the intervention was at least partially school-based, and if the effect estimate's variability was reported. An inverse-variance random effects meta-regression was employed using the primary predictors of component number (single component or multi-component) and intervention length using 20 extracted studies with 23 total effects. The overall pooled effect on cardiorespiratory endurance was statistically significant (Hedges' g = 0.30, 95% C.I.: 0.19⁻0.40; p < 0.001). Using random effects meta-regression, neither component number (b = ⁻0.09, 95% C.I.: ⁻0.40⁻0.23; p = 0.560) or intervention length (b = 0.001, 95% C.I.: ⁻0.002⁻0.004; p = 0.427) yielded a significant modifying effect on cardiorespiratory endurance. School-based physical activity interventions have a significant pooled effect on cardiorespiratory endurance in primary school-aged children. Component number and intervention length does not modify this effect, suggesting other sources for between-study heterogeneity.

Validation of the Modified Shuttle Test to Predict Peak Oxygen Uptake in Youth Asthma Patients Under Regular Treatment

Background: Oxygen uptake (VO₂) evaluations by cardiopulmonary exercise test is expensive and time-consuming. Estimating VO₂ based on a field test would be an alternative.

Objective: To develop and validate an equation to predict VO_2peak based on the modified shuttle test (MST).

Methods: Cross sectional study, with 97 children and adolescents with asthma. Participants were divided in two groups: the equation group (EG), to construct the equation model of VO_2peak, and the cross-validation group (VG). Each subject performed the MST twice using a portable gas analyzer. The peak VO_2peak during MST was used in the equation model. The patients’ height, weight, gender, and distance walked (DW) during MST were tested as independent variables.

Results: The final model [-0.457 + (gender × 0.139) + (weight × 0.025) + (DW × 0.002)] explained 87% of VO_2peak variation. The VO_2peak predicted was similar to VO_2peak measured by gas analyzer (1.9 ± 0.5 L/min and 2.0 ± 0.5 L/min, respectively) (p = 0.67), and presented significant ICC 0.91 (IC95% 0.77 to 0.96); p < 0.001. The Bland–Altman analysis showed low bias (-0.15 L/min) and limits of agreement (-0.65 to 0.35 L/min). There was no difference in DW between EG (760 ± 209 m) and VG (731 ± 180 m), p = 0.51.

Conclusion: The developed equation adequately predicts VO_2peak in pediatric patients with asthma.

Clustering of Health Behaviors and Cardiorespiratory Fitness Among U.S. Adolescents

PURPOSE

Decreased cardiorespiratory fitness (CRF) is associated with an increased risk of cardiovascular disease. However, little is known how the interaction of diet, physical activity (PA), and sedentary time (ST) affects CRF among adolescents. By using a nationally representative sample of U.S. adolescents, we used cluster analysis to investigate the interactions of these behaviors with CRF. We hypothesized that distinct clustering patterns exist and that less healthy clusters are associated with lower CRF.

METHODS

We used 2003-2004 National Health and Nutrition Examination Survey data for persons aged 12-19 years (N = 1,225). PA and ST were measured objectively by an accelerometer, and the American Heart Association Healthy Diet Score quantified diet quality. Maximal oxygen consumption (V˙O₂​max) was measured by submaximal treadmill exercise test. We performed cluster analysis to identify sex-specific clustering of diet, PA, and ST. Adjusting for accelerometer wear time, age, body mass index, race/ethnicity, and the poverty-to-income ratio, we performed sex-stratified linear regression analysis to evaluate the association of cluster with V˙O₂​max.

RESULTS

Three clusters were identified for girls and boys. For girls, there was no difference across clusters for age (p = .1), weight (p = .3), and BMI (p = .5), and no relationship between clusters and V˙O₂​max. For boys, the youngest cluster (p < .01) had three healthy behaviors, weighed less, and was associated with a higher V˙O₂​max compared with the two older clusters.

CONCLUSIONS

We observed clustering of diet, PA, and ST in U.S. adolescents. Specific patterns were associated with lower V˙O₂​max for boys, suggesting that our clusters may help identify adolescent boys most in need of interventions.

The effects of lifestyle changes on serum lipid levels in children in a real life setting

OBJECTIVE

Studies have shown improvement in lipid levels after institution of lifestyle changes in children enrolled in closely monitored programs. There programs are difficult to mimic in real world clinics. We aim to determine if diet and exercise result in improvement in lipid levels in patients seen in a designated lipid clinic in a real life setting.

DESIGN

Retrospective review of patients followed for dyslipidemia at the Texas Children's Hospital Lipid Clinic from May 1, 2012 to May 1, 2015. Patients included were seen more than once, had repeat lipid testing, and abnormal baseline lipid levels. Multivariate analysis using mixed models were performed to compare outcomes in patients who did and did not participate in lifestyle change.

RESULTS

Of the 268 patients seen within the study period, 174 (56% male, 44% female) met inclusion criteria. Median age was 11 years. Compared to patients who did not make lifestyle changes: patients who made only diet changes demonstrated significant improvement in weight only (slope = -1.55, P-value = .014), and those who made only exercise changes demonstrated significant improvements in serum cholesterol (slope = -22.8, P-value = .017) and non-HDL cholesterol (slope = -28.7, P-value = < .01) levels. Patients who participated in both diet and exercise demonstrated significant improvement in weight (slope = -1.13, P-value = .011), diastolic blood pressure (slope = -1.82, P-value = < .01), and serum lipid levels: LDL (slope = -10.8, P-value = 0.017), HDL (slope = 1.52, P-value = .24), Triglycerides (slope = -0.11, P-value = .033) compared to those who did not make lifestyle changes.

CONCLUSIONS

Outpatient management of dyslipidemia is difficult. Only patients who participated in both diet and exercise showed significant improvement in outcomes when compared to those who did not make lifestyle changes.

The CHANGE! Project: Changes in Body Composition and Cardiorespiratory Fitness in 10- to 11-Year-Old Children After Completing the CHANGE! Intervention

PURPOSE

To assess the effects of the Children's Health, Activity and Nutrition: Get Educated! intervention on body size, body composition, and peak oxygen uptake in a subsample of 10- to 11-year-old children.

METHODS

Sixty children were recruited from 12 schools (N = 6 intervention) to take part in the CHANGE! subsample study. Baseline, postintervention, and follow-up measures were completed in October 2010, March-April 2011, and June-July 2011, respectively. Outcome measures were body mass index z score, waist circumference, body composition assessed using dual-energy X-ray absorptiometry (baseline and follow-up only), and peak oxygen uptake.

RESULTS

Significant differences in mean trunk fat mass (control = 4.72 kg, intervention = 3.11 kg, P = .041) and trunk fat % (control = 23.08%, intervention = 17.75%, P = .022) between groups were observed at follow-up. Significant differences in waist circumference change scores from baseline to follow-up were observed between groups (control = 1.3 cm, intervention = -0.2 cm, P = .023). Favorable changes in body composition were observed in the intervention group; however, none of these changes reached statistical significance. No significant differences in peak oxygen uptake were observed.

CONCLUSIONS

The results of the present study suggest the multicomponent curriculum intervention had small to medium beneficial effects on body size and composition health outcomes.

School-based physical activity interventions and physical activity enjoyment: A meta-analysis

The purpose of this meta-analysis was to examine the effectiveness of school-based physical activity interventions on increasing students' physical activity enjoyment. An internet search with several databases using the keywords "Adolescents", "Children", "Enjoyment", "Physical Activity", and "Schools" was performed yielding over 200 published studies. Studies were eliminated based on the lack of experimental manipulation (i.e., non-intervention studies), no assessment of physical activity enjoyment as an outcome variable, a lack of a control or comparison group, and no reporting of the effect estimate's variability (i.e., standard deviation, standard error, etc.). This procedure resulted in 10 studies being examined in the meta-analysis. Data were analyzed in the state of Utah, USA in 2017. The Hartung-Knapp-Sidak-Jonkman method for a random effects meta-analysis was employed with studies being weighted by inverse variance. The pooled Standardized Mean Difference=0.38 (95% C.I. [0.10-0.65], p=0.011). Cochran's Q test showed statistical significance (p<0.001) and the I²=76.6%, suggesting large heterogeneity across the 10 studies. Egger's regression model yielded an intercept coefficient that was statistically significant (bias=3.28, 95% C.I. [0.21-6.36], p=0.039), indicating the presence of small-study effects. This meta-analysis provides evidence that school-based physical activity interventions can be effective in increasing physical activity enjoyment in children and adolescents. However, the magnitude of the pooled effect was small-to-moderate and there was evidence for publication bias and large between-study heterogeneity.

Individual calibration of accelerometers in children and their health-related implications

This study compared children's physical activity (PA) levels, the prevalence of children meeting current guidelines of ≥60 minutes of daily moderate to vigorous PA (MVPA), and PA-health associations using individually calibrated (IC) and empirical accelerometer cutpoints. Data from 75 (n = 32 boys) 10-12 year old children were included in this study. Clustered cardiometabolic (CM) risk, directly measured cardiorespiratory fitness (CRF), anthropometric and 7 day accelerometer data were included within analysis. PA data were classified using Froude anchored IC, Evenson et al. (Evenson, K. R., Catellier, D. J., Gill, K., Ondrak, K. S., & McMurray, R. G. (2008). Calibration of two objective measures of physical activity for children. Journal of Sports Sciences, 26(14), 1557-1565. doi:10.1080/02640410802334196) (Ev) and Mackintosh et al. (Mackintosh, K. A., Fairclough, S. J., Stratton, G., & Ridgers, N. D. (2012). A calibration protocol for population-specific accelerometer cutpoints in children. PLoS One, 7(5), e36919. doi:10.1371/journal.pone.0036919) (Mack) cutpoints. The proportion of the cohort meeting ≥60mins MVPA/day ranged from 37%-56% depending on the cutpoints used. Reported PA differed significantly across the cutpoint sets. IC LPA and MPA were predictors of CRF (LPA: standardised β = 0.32, p = 0.002, MPA: standardised β = 0.27 p = 0.013). IC MPA also predicted BMI Z-score (standardised β = -0.35, p = 0.004). Ev VPA was a predictor of BMI Z-score (standardised β = -0.33, p = 0.012). Cutpoint choice has a substantial impact on reported PA levels though no significant associations with CM risk were observed. Froude IC cutpoints represent a promising approach towards classifying children's PA data.

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.

Predictors of Segmented School Day Physical Activity and Sedentary Time in Children from a Northwest England Low-Income Community

Background: Schools have been identified as important settings for health promotion through physical activity participation, particularly as children are insufficiently active for health. The aim of this study was to investigate the child and school-level influences on children′s physical activity levels and sedentary time during school hours in a sample of children from a low-income community; Methods: One hundred and eighty-six children (110 boys) aged 9–10 years wore accelerometers for 7 days, with 169 meeting the inclusion criteria of 16 h∙day⁻¹ for a minimum of three week days. Multilevel prediction models were constructed to identify significant predictors of sedentary time, light, and moderate to vigorous physical activity during school hour segments. Child-level predictors (sex, weight status, maturity offset, cardiorespiratory fitness, physical activity self-efficacy, physical activity enjoyment) and school-level predictors (number on roll, playground area, provision score) were entered into the models; Results: Maturity offset, fitness, weight status, waist circumference-to-height ratio, sedentary time, moderate to vigorous physical activity, number of children on roll and playground area significantly predicted physical activity and sedentary time; Conclusions: Research should move towards considering context-specific physical activity and its correlates to better inform intervention strategies.

Utility of three anthropometric indices in assessing the cardiometabolic risk profile in children

OBJECTIVES

To evaluate the ability of BMI, WC, and WHtR to identify increased cardiometabolic risk in pre-adolescents.

METHODS

This is a cross-sectional study involving 192 children (10.92 ± 0.58 years, 56% female) from the United Kingdom between 2010 and 2013. Receiver operating characteristic curves determined the discriminatory ability of BMI, WC and WHtR to identify individuals with increased cardiometabolic risk (increased clustered triglycerides, HDL-cholesterol, systolic blood pressure, cardiorespiratory fitness, and glucose).

RESULTS

A WHtR ≥ 0.5 increased the odds by 5.2 (95% confidence interval 2.6 - 10.3) of having increased cardiometabolic risk. Similar associations were observed for BMI and WC. Both BMI-z and WHtR were fair predictors of increased cardiometabolic risk, although BMI-z demonstrated the best trade-off between sensitivity and specificity, 76.1% and 63.6%, compared with 68.1% and 65.5% for WHtR. Cross-validation analysis revealed that BMI-z and WHtR correctly classified 84% of individuals (kappa score = 0.671, 95% CI 0.55, 0.79). The sensitivity of the cut-points suggests that 89.3% of individuals were correctly classified as being at risk with only 10.7% misdiagnosed whereas the specificity of the cut-points indicated that 77.8% of individuals were correctly identified as being healthy with 22.2% of individuals incorrectly diagnosed as being at risk.

CONCLUSIONS

Findings suggest that WHtR provides similar cardiometabolic risk estimates to age and sex adjusted BMI.

Effect of a 12-Week Summer Break on School Day Physical Activity and Health-Related Fitness in Low-Income Children from CSPAP Schools

Background. The purpose of this study was to examine the effect of a 12-week summer break on school day physical activity and health-related fitness (HRF) in children from schools receiving a Comprehensive School Physical Activity Program (CSPAP). Methods. Participants were school-aged children (N = 1,232; 624 girls and 608 boys; mean age = 9.5 ± 1.8 years) recruited from three low-income schools receiving a CSPAP. Physical activity and HRF levels were collected during the end of spring semester 2015 and again during the beginning of fall semester 2015. Physical activity was assessed using the Yamax DigiWalker CW600 pedometer. HRF measures consisted of body mass index (BMI) and the Progressive Aerobic Cardiovascular Endurance Run (PACER). Results. Results from a doubly MANCOVA analysis indicated that pedometer step counts decreased from 4,929 steps in the spring to 4,445 steps in the fall (mean difference = 484 steps; P < 0.001; Cohen's d = 0.30) and PACER laps decreased from 31.2 laps in the spring to 25.8 laps in the fall (mean difference = 5.4 laps; P < 0.001; Cohen's d = 0.33). Conclusions. Children from schools receiving a CSPAP intervention had lower levels of school day physical activity and cardiorespiratory endurance following a 12-week summer break.

Do Interventions to Increase Walking Work? A Systematic Review of Interventions in Children and Adolescents

Background

Physical activity (PA) levels decline as children move into adolescence, with this decline more notable in girls. As a consequence, many young people are failing to meet current PA guidelines. Walking has been a cornerstone of PA promotion in adults and may provide an effective means of increasing PA levels among younger people.

Objective

Our objective was to conduct a systematic review of interventions aimed at promoting increased levels of walking among children and adolescents.

Methods

Eight electronic databases—CINAHL, Cochrane Library CENTRAL database, EMBASE, Medline OVID, PsycINFO, Scopus, SPORTDiscus and Web of Knowledge—were searched from their inception up to January 2015 using predefined text terms: walking terms AND intervention terms AND population terms AND (physical activity OR exercise). Reference lists of published systematic reviews and original articles included in the review were also screened. Included studies were randomised and non-randomised controlled trials reporting a specific measure of walking levels (self-reported or objective) to assess the effectiveness of interventions aimed at promoting walking in children and adolescents (aged 5–18 years). Only full articles published in English in peer-reviewed journals were included. Risk of bias and behaviour change techniques of included studies were assessed.

Results

Twelve studies were included in this review. The majority of studies assessed interventions delivered within an educational setting, with one study conducted within the family setting. Nine of the included studies reported significant increases in walking in intervention groups versus controls. Commonly employed behaviour change techniques within successful interventions included goals and planning, feedback and monitoring, social support and repetition and substitution.

Conclusions

Walking interventions, particularly those conducted in the school environment, have the potential to increase PA in children and adolescents. Conclusions on which interventions most effectively increased walking behaviours in this population were hindered by the limited number of identified interventions and the short duration of interventions evaluated. The short-term effectiveness of the majority of included studies on levels of walking in this population is promising and further research, particularly within non-educational settings and targeted at sub-groups (e.g. adolescent girls and overweight/obese children and adolescents), is warranted.

Electronic supplementary material

The online version of this article (doi:10.1007/s40279-015-0432-6) contains supplementary material, which is available to authorized users.

Active children through incentive vouchers - evaluation (ACTIVE): a mixed-method feasibility study

Background

Adolescents face many barriers to physical activity, demonstrated by the decline in physical activity levels in teenage populations. This study aimed to assess the feasibility of overcoming such barriers via the implementation of an activity-promoting voucher scheme to teenagers in deprived areas.

Methods

All Year 9 pupils (n = 115; 13.3 ± 0.48 years; 51 % boys) from one secondary school in Wales (UK) participated. Participants received £25 of activity vouchers every month for six months for physical activity or sporting equipment. Focus groups (n = 7), with 43 pupils, and qualitative interviews with teachers (n = 2) were conducted to assess feasibility, in addition to a process evaluation utilising the RE-AIM framework. Quantitative outcomes at baseline, five months (during intervention) and twelve months (follow-up) included: physical activity (accelerometer), aerobic fitness (12 min Cooper run) and self-reported activity (PAQ-A). Motivation to exercise (BREQ-2) was measured three months post-baseline and at follow-up.

Results

Qualitative findings showed that vouchers encouraged friends to socialise through activity, provided opportunities to access local activities that pupils normally could not afford, and engaged both those interested and disinterested in physical education. Improvements in weekend moderate-to-vigorous physical activity and reductions in sedentary behaviour were observed in both sexes. Boys’ fitness significantly improved during the voucher scheme. ‘Non-active’ pupils (those not meeting recommended guidelines of 60 mins∙day⁻¹) and those with higher motivation to exercise had higher voucher use.

Conclusions

Adolescents, teachers and activity providers supported the voucher scheme and felt the vouchers enabled deprived adolescents to access more physical activity opportunities. Voucher usage was associated with improved attitudes to physical activity, increased socialisation with friends and improved fitness and physical activity; presenting interesting avenues for further exploration in a larger intervention trial.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-016-3381-6) contains supplementary material, which is available to authorized users.

Cross-sectional study of ethnic differences in physical fitness among children of South Asian, black African-Caribbean and white European origin: the Child Heart and Health Study in England (CHASE)

OBJECTIVE

Little is known about levels of physical fitness in children from different ethnic groups in the UK. We therefore studied physical fitness in UK children (aged 9-10 years) of South Asian, black African-Caribbean and white European origin.

DESIGN

Cross-sectional study.

SETTING

Primary schools in the UK.

PARTICIPANTS

1625 children (aged 9-10 years) of South Asian, black African-Caribbean and white European origin in the UK studied between 2006 and 2007.

OUTCOME MEASURES

A step test assessed submaximal physical fitness from which estimated VO2 max was derived. Ethnic differences in estimated VO2 max were estimated using multilevel linear regression allowing for clustering at school level and adjusting for age, sex and month as fixed effects.

RESULTS

The study response rate was 63%. In adjusted analyses, boys had higher levels of estimated VO2 max than girls (mean difference 3.06 mL O2/min/kg, 95% CI 2.66 to 3.47, p<0.0001). Levels of estimated VO2 max were lower in South Asians than those in white Europeans (mean difference -0.79 mL O2/min/kg, 95% CI -1.41 to -0.18, p=0.01); levels of estimated VO2 max in black African-Caribbeans were higher than those in white Europeans (mean difference 0.60 mL O2/min/kg, 95% CI 0.02 to 1.17, p=0.04); these patterns were similar in boys and girls. The lower estimated VO2 max in South Asians, compared to white Europeans, was consistent among Indian, Pakistani and Bangladeshi children and was attenuated by 78% after adjustment for objectively measured physical activity (average daily steps).

CONCLUSIONS

South Asian children have lower levels of physical fitness than white Europeans and black African-Caribbeans in the UK. This ethnic difference in physical fitness is at least partly explained by ethnic differences in physical activity.

Effect of Physically Active Academic Lessons on Body Mass Index and Physical Fitness in Primary School Children

BACKGROUND

Preventing overweight and improving physical fitness in primary school children is a worldwide challenge, and physically active intervention programs usually come with the cost of academic instruction time. This study aimed to investigate effects of physically active academic lessons on body mass index (BMI) and physical fitness in primary school children.

METHODS

Dutch children attending second- or third-grade class from 12 primary schools (N = 376; 8.1 ± 0.7 years) were randomly assigned to a 22-week intervention program or to the control group. In addition to measuring BMI before and after the intervention, physical fitness was measured with 5 items of the Eurofit test battery, measuring cardiovascular and muscular fitness.

RESULTS

Multilevel analysis showed a significant interaction effect between condition (intervention vs control) and grade (B = -0.47; p < .05). For third-grade children, BMI of the intervention group did not change significantly during the intervention period, whereas a significant increase was found in the control group. No significant main or interaction effects were found for cardiovascular or muscular fitness.

CONCLUSIONS

The current physically active academic lessons had positive effects on BMI in third-grade children, but had no effects on cardiovascular and muscular fitness.

Long-term effects of physically active academic lessons on physical fitness and executive functions in primary school children

Integrating physical activity into the curriculum has potential health and cognitive benefits in primary school children. The aim of this study was to investigate the effects of physically active academic lessons on cardiovascular fitness, muscular fitness and executive functions. In the current randomized controlled trial, 499 second and third graders within 12 primary schools (mean age = 8.1 ± 0.7) were randomized to the intervention (n = 249) or control condition (n = 250). The physically active academic lessons were given for 2 consecutive school years, 22 weeks per year, three times a week, with a duration of 20-30 min per lesson. Multiple tests were administered before, between and after the intervention period, measuring cardiovascular fitness, muscular fitness and executive functions. Multilevel analysis accounted for the nested structure of the children within classes and schools. Results showed a larger improvement in speed-coordination (B = -0.70,P = 0.002) and a lower improvement in static strength (B = -0.92,P < : 0.001) for the intervention group compared with the control group. The current lessons did not result in a significant change in executive functions.

Cross-sectional associations between high-deprivation home and neighbourhood environments, and health-related variables among Liverpool children

OBJECTIVES

(1) To investigate differences in health-related, home and neighbourhood environmental variables between Liverpool children living in areas of high deprivation (HD) and medium-to-high deprivation (MD) and (2) to assess associations between these perceived home and neighbourhood environments and health-related variables stratified by deprivation group.

DESIGN

Cross-sectional study.

SETTING

10 Liverpool primary schools in 2014.

PARTICIPANTS

194 children aged 9-10 years.

MAIN OUTCOME MEASURES

Health-related variables (self-reported physical activity (PA) (Physical Activity Questionnaire for Older Children, PAQ-C), cardiorespiratory fitness, body mass index (BMI) z-scores, waist circumference), home environment variables: (garden/backyard access, independent mobility, screen-based media restrictions, bedroom media) and neighbourhood walkability (Neighbourhood Environment Walkability Scale for Youth, NEWS-Y).

EXPLANATORY MEASURES

Area deprivation.

RESULTS

There were significant differences between HD and MD children's BMI z-scores (p<0.01), waist circumference (p<0.001) and cardiorespiratory fitness (p<0.01). HD children had significantly higher bedroom media availability (p<0.05) and independent mobility scores than MD children (p<0.05). MD children had significantly higher residential density and neighbourhood aesthetics scores, and lower crime safety, pedestrian and road traffic safety scores than HD children, all of which indicated higher walkability (p<0.01). HD children's BMI z-scores (β=-0.29, p<0.01) and waist circumferences (β=-0.27, p<0.01) were inversely associated with neighbourhood aesthetics. HD children's PA was negatively associated with bedroom media (β=-0.24, p<0.01), and MD children's PA was positively associated with independent mobility (β=0.25, p<0.01). MD children's independent mobility was inversely associated with crime safety (β=-0.28, p<0.01) and neighbourhood aesthetics (β=-0.24, p<0.05).

CONCLUSIONS

Children living in HD areas had the least favourable health-related variables and were exposed to home and neighbourhood environments that are unconducive to health-promoting behaviours. Less access to bedroom media equipment and greater independent mobility were strongly associated with higher PA in HD and MD children, respectively. Facilitating independent mobility and encouraging outdoor play may act as effective strategies to enhance PA levels and reduce sedentary time in primary school-aged children.

Cumulative incidence of youth obesity is associated with low cardiorespiratory fitness levels and with maternal overweight

Abstract This longitudinal study evaluated the association between the incidence of youth overweight/obesity (Ow/Ob) and low levels of cardiorespiratory fitness (CRF) over 4 years and youths' and their parents' demographic and nutritional characteristics. The randomized sample comprised 398 youth, aged 7-17 years at baseline, from a city in southern Brazil. Subjects were classified as being Ow/Ob according to international body mass index (BMI) parameters. Parental weight and height were determined by direct questioning. Youth CRF was measured by a 9-minute walk-and-run test. The cumulative incidences of Ow/Ob and of low CRF levels were 25.1% and 20.5%, respectively. Relative to other youth, youth who were classified as "unhealthy" at baseline (with respect to CRF) and by the fourth year were more likely to be classified as Ow/Ob (relative risks: 1.12 and 1.10, respectively). Youth whose mothers were categorized as Ow/Ob were at higher risk of being classified as Ow/Ob than youth whose mothers had normal BMIs (relative risks: 1.19 at baseline and 1.20 in the fourth year). The incidence of Ow/Ob among the former youth was associated with low CRF levels and with maternal Ob.

Predictors and grade level trends of school day physical activity achievement in low-income children from the U.S

The achievement of recommended levels (≥ 30 min/day) of school moderate-to-vigorous physical activity (MVPA) is paramount to decrease risk of chronic disease in children from low-income families. The purpose of this study was to examine the predictors and grade-level trends of school day MVPA achievement in low-income children. Data were collected during the Fall of 2014 on 1232 children (Mean age = 8.8 ± 1.6 years; 625 girls, 607 boys) recruited from three low-income schools from the state of Utah in the U.S. Children wore pedometers for one school week and a stratified random subsample (n = 533) also wore accelerometers to record sedentary time and MVPA. Generalized linear mixed models were employed to calculate odds ratios for achieving school MVPA standards (≥ 30 min/day) from various predictors and to determine odds of achievement across grade levels, accounting for school and classroom clustering. Odds of meeting MVPA standards were 3 times greater if a student achieved at least 6000 steps during the school day (p < 0.01), and were 55% lower for every 1% increase in sedentary time (p < 0.001). Older children had 26% lower odds of meeting the recommended levels of MVPA compared to children in an immediately younger grade level (p < 0.05). A significant proportion of MVPA variance was explained by classroom and school affiliation (Rho = 0.09 to 0.54, p < 0.001). Daily steps, sedentary times, grade level, and classroom and school affiliation associate with school MVPA achievement in low-income children.

Quantitative physical activity assessment of children and adolescents in a rural population from Eastern Nepal

OBJECTIVES

We report cross-sectional, objectively measured physical activity data for 399 children and adolescents aged 6 to 18 years. We evaluated physical activity of children and adolescents, considered time spent in each activity intensity category, and explored the impact of growth disruption (stunting and wasting) on physical activity patterns.

METHODS

Participants wore an Actical (Mini-Mitter, Bend, OR) omnidirectional accelerometer for one week as part of their annual visit to the Jiri Growth Study. The percentage of time spent in standard activity intensities were computed using standard metabolic equivalents (METS) cutpoints and compared by chronological age, sex, and school versus non-school days.

RESULTS

Primary findings include (1) children are more active on non-school days and adolescents are more active during the school week; (2) Jirel children do not exhibit the reduction in physical activity that most Western populations experience during the transition from childhood to adolescence; and (3) Jirel children and adolescents routinely meet the suggested one hour/day MVPA threshold; (4) Stunting is prevalent and factors leading to this growth disruption may contribute to the amount of time in sedentary or light physical activity.

CONCLUSIONS

We report child and adolescent physical activity patterns from the Jirel population of eastern Nepal. In this rural context, children and adolescents are more active than populations reported from Western contexts. This key finding has important biomedical implications for the maintenance of healthy body composition, skeletal health, and other health traits.

Physical activity and play behaviours in children and young people with intellectual disabilities: A cross-sectional observational study

The benefits of physical activity and active play for children and young people are well established. However, there is a lack of physical activity research involving children and young people with intellectual disabilities. This study investigated habitual physical activity and recess play behaviour in 70 5- to 15-year-old participants with intellectual disabilities using objective methods (accelerometers) and systematic observation techniques. Results showed that few children were active enough to benefit their physical health (23% of the cohort). No differences in habitual physical activity, sedentary behaviour, or recess play behaviours were observed between boys and girls. Participants spent most of their recess time alone or playing in small groups, with no participants engaging in large group play. Older participants spent more recess time playing in small groups rather than playing alone and participants with Autistic Spectrum Disorder spent more time engaged in active pursuits and less time standing than non-Autism Spectrum Disorder participants. Positive correlations were observed between time spent alone and physical activity. These findings contrast with those typically observed in a mainstream school setting. In conclusion, interventions designed from formative research are needed to promote physical activity within this population. Implications for school psychologists are discussed.

The combined effect of physical activity and sedentary behaviors on a clustered cardio-metabolic risk score: The Helena study

BACKGROUND/OBJECTIVE

Increased physical activity (PA) and decreased sedentary behaviors (SBs) may have beneficial effects on cardio-metabolic risk in adolescents. The aim of this study was to examine the associations between independent/combined effects of PA and SB with individual/clustered cardio-metabolic risk factors.

METHODS

A sample of 769 adolescents (12.5-17.5 years) from the HELENA cross-sectional study (Healthy Lifestyle in Europe by Nutrition in Adolescence) and with valid data on metabolic risk factors were included.

RESULTS

Concerning moderate-to-vigorous-PA (MVPA) and vigorous-PA (VPA), measured with accelerometers, girls tended to do more MVPA (36%) and VPA (114%) than boys. Unadjusted analyses show a positive association between "PA ≥ 60 min/d; SB ≥ 2 h" and the ratio TC/HDL-c (β = 0.27; 95%CI 0.01 to 0.52; p < 0.05), and a negative association between "MVPA ≥ 60 min/d; SB < 2h" with the ∑ 4Skinfolds (β = -0.32; 95%CI -0.61 to -0.02; p<0.05). Moreover, "SB ≥ 2 h/d" was associated with increased cardio-metabolic risk (PR 1.59; 95%CI 1.05 to 2.39; p < 0.05), while "PA ≥ 60 min/d; SB < 2h" had a protective effect against cardio-metabolic risk (PR 0.48; 95%CI 0.25 to 0.91; p < 0.05). After adjustment for potential confounders, a positive association between SB and ∑ 4Skinfolds was shown (β = 0.28; 95%CI 0.04 to 0.53; p < 0.05). Furthermore, VO2max (mL/kg/min) tends to increase in those participants who do higher VPA and less SB (p = 0.042), and there was a protective effect of "VPA ≥ 30 min/d; SB < 2h" against cardio-metabolic risk (PR 0.24; 95%CI 0.07 to 0.85; p < 0.05).

CONCLUSION

The current study suggests that adolescents should be encouraged to decrease sedentary lifestyle and increase physical activity, especially vigorous physical activity, in order to reduce cardio-metabolic risk.

Prediction of Optimal Daily Step Count Achievement from Segmented School Physical Activity

Optimizing physical activity in childhood is needed for prevention of disease and for healthy social and psychological development. There is limited research examining how segmented school physical activity patterns relate to a child achieving optimal physical activity levels. The purpose of this study was to examine the predictive relationship between step counts during specific school segments and achieving optimal school (6,000 steps/day) and daily (12,000 steps/day) step counts in children. Participants included 1,714 school-aged children (mean age =9.7±1.0years) recruited across six elementary schools. Physical activity was monitored for one week using pedometers. Generalized linear mixed effects models were used to determine the adjusted odds ratios (ORs) of achieving both school and daily step count standards for every 1,000 steps taken during each school segment. The school segment that related in strongest way to a student achieving 6,000 steps during school hours was afternoon recess (OR = 40.03;P<0.001) and for achieving 12,000 steps for the entire day was lunch recess (OR = 5.03;P<0.001). School segments including lunch and afternoon recess play an important role for optimizing daily physical activity in children.