Physical activity and circulating inflammatory markers and cytokines during pregnancy: A population-based cohort study.

INTRODUCTION: Physical activity (PA) during pregnancy has numerous benefits, which may be mediated via effects on the immune system. However, supportive evidence is inconsistent and is mainly from studies in high-risk groups. We estimated the effect of PA during pregnancy on systemic inflammatory markers and cytokines in mothers recruited in the Barwon infant study. MATERIAL AND METHODS: The Barwon infant study is a prebirth cohort of 1064 mothers recruited in the Barwon Region of Victoria, Australia. Participants reported their previous week's PA at their 28-week antenatal appointment using the International PA Questionnaire. Women were grouped into low, moderate, and high PA categories based on daily duration and weekly frequency of walking, moderate- or vigorous-intensity PA. Women reporting moderate levels of PA, consistent with current recommendations, served as the comparison group. Markers of systemic inflammation, high-sensitivity C-reactive protein (hsCRP), glycoprotein acetyls (GlycA), and 17 cytokines were measured at 28 weeks gestation and log transformed as appropriate. Regression analyses adjusted for maternal smoking, gestational diabetes mellitus, prepregnancy BMI, and household size were performed. RESULTS: Compared to women in the moderate group (n = 371, 42%), women reporting low PA (n = 436, 50%) had 10.1% higher hsCRP (95% CI (3.7% to 16.6%), p < 0.01) while women in high PA (n = 76, 9%) had a 14% higher hsCRP (95% CI (3.1% to 24.8%), p = 0.01). Women in the high PA category had higher interleukin (IL)-4 (q = 0.03) and IL-9 (q = 0.03) levels compared to those in moderate category. Each vigorous MET minute/week was associated with lower GlycA (ß = -0.004, 95% CI (-0.044 to 0.035); p = 0.03). CONCLUSIONS: Low and high PA are each associated with higher hsCRP than moderate PA, suggesting that undertaking the recommended moderate PA during pregnancy decreases systemic inflammation. High PA affects T cell-associated cytokines during pregnancy. Evidence from our study suggests that PA can modulate the immune responses during pregnancy. Studies are now required to assess whether PA during pregnancy impacts maternal and infant clinical outcomes by modifying inflammatory responses.

Cost-effectiveness of reducing children's sedentary time and increasing physical activity at school: the Transform-Us! intervention.

BACKGROUND: Improving physical activity and reducing sedentary behavior represent important areas for intervention in childhood in order to reduce the burden of chronic disease related to obesity and physical inactivity in later life. This paper aims to determine the cost-effectiveness of a multi-arm primary school-based intervention to increase physical activity and/or reduce sedentary time in 8-9 year old children (Transform-Us!). METHODS: Modelled cost-utility analysis, using costs and effects from a cluster randomized controlled trial of a 30-month intervention that used pedagogical and environmental strategies to reduce and break up sedentary behaviour (SB-I), promote physical activity (PA-I), or a combined approach (PA + SB-I), compared to current practice. A validated multiple-cohort lifetable model (ACE-Obesity Policy model) estimated the obesity and physical activity-related health outcomes (measured as change in body mass index and change in metabolic equivalent task minutes respectively) and healthcare cost-savings over the cohort's lifetime from the public-payer perspective, assuming the intervention was delivered to all 8-9 year old children attending Australian Government primary schools. Sensitivity analyses tested the impact on cost-effectiveness of varying key input parameters, including maintenance of intervention effect assumptions. RESULTS: Cost-effectiveness results demonstrated that, when compared to control schools, the PA-I and SB-I intervention arms were "dominant", meaning that they resulted in net health benefits and healthcare cost-savings if the intervention effects were maintained. When the costs and effects of these intervention arms were extrapolated to the Australian population, results suggested significant potential as obesity prevention measures (PA-I: 60,780 HALYs saved (95% UI 15,007-109,413), healthcare cost-savings AUD641M (95% UI AUD165M-$1.1B); SB-I: 61,126 HALYs saved (95% UI 11,770 - 111,249), healthcare cost-savings AUD654M (95% UI AUD126M-1.2B)). The PA-I and SB-I interventions remained cost-effective in sensitivity analysis, assuming the full decay of intervention effect after 10 years. CONCLUSIONS: The PA-I and SB-I Transform-Us! intervention arms represent good value for money and could lead to health benefits and healthcare cost-savings arising from the prevention of chronic disease in later life if intervention effects are sustained. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number (ISRCTN83725066). Australia and New Zealand Clinical Trials Registry Number (ACTRN12609000715279).

Fathers' perceived role, self-efficacy and support needs in promoting positive nutrition and physical activity in the first 2000 days of life: a mixed methods study.

BACKGROUND: The first 2000 days of life are a crucial and opportunistic time to promote positive dietary and physical activity behaviours that can continue throughout life. The bulk of research on the impact of parents promoting positive dietary and physical activity behaviours has been on mothers, with the impact of fathers rarely investigated. The aim of this study is to investigate fathers' perceived role, self-efficacy and support needs in promoting positive dietary and physical activity behaviours in early childhood. METHODS: A sequential explanatory mixed methods study design consisted of a cross sectional survey of Australian fathers (n = 200) from a convenience sample, followed by semi-structured qualitative interviews (n = 21) with a purposeful sample of Australian fathers. RESULTS: Quantitative survey data revealed that more than 90.0% of fathers agreed that it is important to role model healthy eating and participating in physical activity with their babies, toddlers and children. A majority of fathers were confident in getting their child to eat fruit/ vegetables (90%) and playing with their child (80%). When searching for information about nutrition and physical activity, the highest proportion of fathers nominated online sources (52%) as their preferred source in survey data. Qualitative interview data revealed that while fathers exhibited high self-efficacy in their abilities, this was susceptible to deterioration due to feelings of isolation, pressures of fatherhood, a lack of information and resources that are father specific, and difficulties navigating the different types of information/resources to find what is right for them. CONCLUSIONS: Although possessing self-efficacy, being committed and seeking knowledge, many fathers found that useful information was hard to find and understand. Appropriate resources are therefore required to support the specific needs of fathers to promote positive dietary and physical activity behaviours in their infants and young children.

Is level of implementation linked with intervention outcomes? Process evaluation of the TransformUs intervention to increase children's physical activity and reduce sedentary behaviour.

BACKGROUND: TransformUs was a four-arm school-based intervention to increase physical activity and reduce sedentary behaviour among primary school children. Pedagogical and environmental strategies targeted the classroom, school grounds and family setting. The aims of this study were to evaluate program fidelity, dose, appropriateness, satisfaction and sustainability, and associations between implementation level and outcomes among the three intervention arms. METHODS: At baseline, 18-months (mid-intervention) and 30-months (post-intervention), teachers, parents and children completed surveys, and children wore GT3X ActiGraph accelerometers for 8 days at each time point to determine physical activity and sedentary time. Implementation data were pooled across the three intervention groups and teachers were categorised by level of implementation: (i) 'Low' (< 33% delivered); (ii) 'Moderate' (33-67% delivered); and (iii) 'High' (> 67% delivered). Linear and logistic mixed models examined between group differences in implementation, and the association with children's physical activity and sedentary time outcomes. Qualitative survey data were analysed thematically. RESULTS: Among intervention recipients, 52% (n = 85) of teachers, 29% (n = 331) of parents and 92% (n = 407) of children completed baseline evaluation surveys. At 18-months, teachers delivered on average 70% of the key messages, 65% set active/standing homework, 30% reported delivering > 1 standing lesson/day, and 56% delivered active breaks per day. The majority of teachers (96%) made activity/sports equipment available during recess and lunch, and also used this equipment in class (81%). Fidelity and dose of key messages and active homework reduced over time, whilst fidelity of standing lessons, active breaks and equipment use increased. TransformUs was deemed appropriate for the school setting and positively received. Implementation level and child behavioural outcomes were not associated. Integration of TransformUs into existing practices, children's enjoyment, and teachers' awareness of program benefits all facilitated delivery and sustainability. CONCLUSIONS: This study demonstrated that intervention dose and fidelity increased over time, and that children's enjoyment, senior school leadership and effective integration of interventions into school practices facilitated improved intervention delivery and sustainability. Teacher implementation level and child behavioural outcomes were unrelated, suggesting intervention efficacy was achieved irrespective of implementation variability. The potential translatability of TransformUs into practice contexts may therefore be increased. Findings have informed scale-up of TransformUs across Victoria, Australia. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number ISRCTN83725066; Australian New Zealand Clinical Trials Registry Number ACTRN12609000715279. Registered 19 August 2009. Available at: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=308387&isReview=true.

Determinants of rapid infant weight gain: A pooled analysis of seven cohorts.

OBJECTIVE: Rapid weight gain (RWG) in infancy is strongly associated with subsequent obesity risk, but little is known about the factors driving RWG. This study explored the child and maternal factors associated with infant RWG. METHODS: Data from seven Australian and New Zealand cohorts were used (n = 4542). Infant RWG was defined as a change in weight z-score ≥0.67 from birth to age 1 year. Univariable and multivariable logistic regression assessed the association between child and maternal factors and infant RWG in each cohort. Meta-analysis was conducted to obtain pooled effect sizes. RESULTS: Multivariable analyses revealed boys were more likely to experience RWG (OR 1.42 95% CI 1.22, 1.66) than girls. Higher birth weight in kg (OR 0.09, 95% CI 0.04, 0.20) and gestational age in weeks (OR 0.69, 95% CI 0.48, 0.98) were associated with lower RWG risk. Children who were breastfed for ≥6 months showed lower RWG risk (OR 0.45, 95% CI 0.38, 0.53). Children of native-born versus overseas-born women appeared to have higher RWG risk (OR 1.37, 95% CI 0.99, 1.90). Maternal smoking during pregnancy increased RWG risk (OR 1.60, 95% CI 1.28, 2.01), whereas children who started solids ≥6 months (OR 0.77, 95% CI 0.63, 0.93) and children with siblings (OR 0.68, 95% CI 0.57, 0.81) showed lower RWG risk in univariable analysis, but these associations were attenuated in multivariable analysis. No association was found for maternal age, education, marital status and pre-pregnancy BMI. CONCLUSION: Maternal country of birth, smoking status, child sex, birth weight, gestational age, infant feeding and parity were potential determinants of infant RWG.

Mapping intervention components from a randomized controlled trial to scale-up of an early life nutrition and movement intervention: The INFANT program.

Introduction: Early life parent-focused interventions can effectively improve infant and child nutrition and movement (physical activity and sedentary behavior) as well as parents' health behaviors. Scale-up of such interventions to real-world settings is essential for population-wide benefits. When progressing to scale-up, intervention components may be modified to reflect contextual factors and promote feasibility of scale-up. The INFANT program, an efficacious early life nutrition and movement behavioral intervention began as a randomized controlled trial (RCT), was modified after a small-scale translation, and is currently being scaled-up in Victoria, Australia. This study mapped and compared discrete intervention components of both the original RCT and the scaled-up version of INFANT to examine modifications for scaling up. Methods: Discrete intervention components, specifically the target behaviors (child-related and parent-related behaviors), delivery features and behavior change techniques (BCTs) from the RCT and the scaled-up program were coded and mapped using established frameworks and taxonomies. Publications and unpublished materials (e.g., facilitator notes, handouts, videos, app) were coded. Coding was performed independently in duplicate, with final coding validated in a meeting with interventionists. Interventionists reported the rationale for modifications made. Results: The INFANT RCT and scaled-up version targeted the same obesity prevention-related nutrition and movement behaviors. Key modified delivery features at scale-up included reduced number of sessions, a broader range of professionals facilitating groups, the addition of a mobile app for parents replacing hard-copy materials and tangible tools (e.g., pedometers), and broadening of content (e.g., early feeding, updated 24-h movement guidelines). BCTs used across the RCT and scale-up sessions were unchanged. However, the BCTs identified in the between-session support materials were almost double for the scale-up compared with the RCT, primarily due to the reduced number of sessions and the app's capacity to include more content. Conclusions: INFANT is one of few early life nutrition and movement behavioral interventions being delivered at scale. With INFANT as an example, this study provides critical understanding about what and why intervention components were altered as the RCT was scaled-up. Unpacking these intervention modifications provides important insights for scale-up feasibility, outcome effects, and how to optimize implementation strategies for population-level benefits.

How to Change Young Children's Physical Activity and Sedentary Behavior: Mechanisms of Behavior Change in the INFANT Cluster Randomized Controlled Trial.

BACKGROUND: Understanding the mechanisms (mediators) of behavior change is crucial to designing more effective interventions. However, this is rarely reported. This paper investigates the mechanisms that explain the lack of intervention effect on physical activity and the significant effect on television viewing time from an early childhood trial. METHODS: Secondary analyses were undertaken of data from a cluster randomized controlled trial. The Melbourne Infant Feeding, Activity and Nutrition Trial (INFANT) was a 15-month group program promoting obesity-protective behaviors from the age of 4 months. Outcomes relevant to the current study were child physical activity (accelerometer), television viewing time (maternal report) and 12 potential mediator scales (maternal report). Linear regression models used the product of coefficients method with a joint significance test. RESULTS: Complete data were from 398 mother-child dyads. Despite weak evidence of an intervention effect on the mother's physical activity knowledge and optimism, there was no effect on children's physical activity, and no clear mechanisms were identified. An intervention effect was observed for the mothers' television knowledge (unstandardized regression coefficient for a path (a) = 0.34, 95% confidence interval (CI95) = 0.22, 0.45), with weak evidence for maternal efficacy (a = 0.11, CI95 = -0.02, 0.24) and the use of television (a = -0.10, CI95 = -0.22, 0.01). The intervention impact on television knowledge explained 75% of the difference between the intervention and control groups in children's television viewing. CONCLUSIONS: In the very early childhood period, as mothers are commencing their parenting journey, improving their behavioral knowledge appears to be the biggest contributor to reducing child television viewing, constituting a relatively simple strategy that could be implemented across clinical and public health settings. In contrast, it remains unclear what mechanisms may increase physical activity levels in this age group.

Volume and accumulation patterns of physical activity and sedentary time: longitudinal changes and tracking from early to late childhood.

BACKGROUND: Physical activity (PA) decreases and sedentary time (SED) increases across childhood, with both behaviours tracking. However, no studies have examined how accumulation patterns of PA and SED (i.e., prolonged bouts, frequency of breaks in sedentary time) change and track over time. The aim of this study was to investigate longitudinal changes in and tracking of total volume and accumulation patterns of SED, light-intensity PA (LPA), moderate-intensity PA (MPA), vigorous-intensity PA (VPA) among boys and girls. METHODS: In 2008/09 (T1), children in HAPPY (3-5y; n = 758) in Melbourne, Australia wore ActiGraph GT1M accelerometers to objectively assess SED, LPA, MPA and VPA. This was repeated at age 6-8y (T2; n = 473) and 9-11y (T3; n = 478). Ten pattern variables were computed: bouts of ≥ 5-, ≥ 10-, ≥ 15- and ≥ 20-min for SED, ≥ 1- and ≥ 5-min for LPA, ≥ 1-min for MPA, ≥ 1- and ≥ 5-min for VPA, and breaks in SED (interruptions of > 25 counts 15 s- 1). Longitudinal mixed models examined changes from T1-3, controlling for T1 age. Generalized estimating equations assessed tracking over the three time points, controlling for T1 age and time between measurements. Analyses were stratified by sex. RESULTS: Total volume and bouts of SED and SED breaks increased, while total volume and bouts of LPA decreased for both sexes. There was a small decrease in total volume of MPA for girls, but time spent in ≥ 1-min bouts increased for both sexes. Total volume of VPA increased for both sexes, with time spent in ≥ 1-min bouts increasing for boys only. All volume and pattern variables tracked moderately for boys, except for all SED bouts ≥ 15-min, LPA bouts ≥ 5-min and MPA bouts ≥ 1-min (which tracked weakly). For girls, total SED and SED bouts ≥ 1-min tracked strongly, total volume of LPA, MPA and VPA, ≥ 5- and ≥ 10-min SED bouts, and ≥ 1-min LPA and MPA bouts tracked moderately, and SED breaks, all SED bouts ≥ 15 min, LPA bouts ≥ 5 min and all VPA bouts tracked weakly. CONCLUSIONS: Patterns of SED and PA change from early to late childhood; with the exception of SED breaks and VPA, changes were detrimental. Total volumes and short bouts tended to track more strongly than longer bouts. Interventions to prevent declines in PA and increases in SED are important from early in life.

Variation in outcomes of the Melbourne Infant, Feeding, Activity and Nutrition Trial (INFANT) according to maternal education and age 2 and 3·5 years post-intervention.

OBJECTIVE: This study aimed to assess whether the long-term effectiveness of the Melbourne Infant, Feeding, Activity and Nutrition Trial (INFANT) at 2 and 3·5 years post-intervention varied according to maternal education and age. DESIGN: Two and 3·5 years post-intervention follow-up of the INFANT cluster-randomised controlled trial. Outcomes at both follow-ups included children's BMI z-scores, physical activity (ActiGraph), television viewing (parental report) and dietary intake (3 × 24-h dietary recalls). Dichotomous moderator variables included maternal education (university v. no university) and age (< 32 v. ≥ 32 years). SETTING: Population based. PARTICIPANTS: Families completing the 15-month programme (n 492) were invited to participate in the follow-ups when their child was 3·6 and 5 years old. RESULTS: At the 2-year follow-up, the intervention effects on vegetable (positive) and sweet snack (negative) intake were greater in children with higher educated mothers, whereas water consumption (positive) was greater in children with lower educated mothers. At the 2-year follow-up, the intervention was more effective in increasing water consumption in children with younger mothers and decreasing sweet snack intake in children with older mothers (opposite result observed at the 3·5-year follow-up). At the 3·5-year follow-up, children with younger and older mothers increased and decreased their consumption of savoury snacks, respectively. CONCLUSIONS: Moderation by maternal education and age were observed for some outcomes; however, clear patterns were not evident at both follow-ups, with little consistency across outcomes. This indicates that INFANT was more-or-less equally effective in children irrespective of their mother's education level or age, which is important in community-based interventions.

Is replacing sedentary time with bouts of physical activity associated with inflammatory biomarkers in children?

This study aimed to investigate the theoretical impact of reallocating a specific amount of sedentary time with an equal amount of (a) total and (b) ≥1-minute bout-accumulated time spent in different activity intensities, on inflammatory biomarkers in 8- to 9-year-old children. Accelerometry and inflammatory biomarker baseline data from the Transform-Us! Study (complete cases n = 149) were utilized. Isotemporal linear models with the Gaussian distribution and identity link functions were used to assess associations between the activity replacements and seven individual inflammatory biomarkers, including C-reactive protein (CRP), and Interleukin (IL)-2, IL-6, IL-8, and IL-10, as well as combined inflammatory and pro-inflammatory composite scores. Eighty-five percent of children met physical activity recommendations. Replacing 10 minutes of sedentary time per day with VPA, regardless of how this was accumulated, was beneficially associated with CRP and both combined composite scores. In contrast, replacing 10 min/day of sedentary time with ≥ 1-minute MPA bouts was detrimentally associated with CRP and the inflammatory composite score. Substitutions with other activity intensities were not significantly associated with any individual inflammatory biomarkers, or combined inflammatory and pro-inflammatory composite scores. In healthy and active school-aged children, evidence of the theoretical impact of replacing sedentary time with physical activity, regardless of intensity or accumulation, on markers of systemic inflammation was limited. Longitudinal research is needed to investigate the long-term impacts of reallocating sedentary time with physical activity, and particularly VPA, for inflammatory biomarkers in children, including those with increased risk of inflammation.

Long-term outcomes (2 and 3.5 years post-intervention) of the INFANT early childhood intervention to improve health behaviors and reduce obesity: cluster randomised controlled trial follow-up.

BACKGROUND: The few health behavior interventions commencing in infancy have shown promising effects. Greater insight into their longer-term benefits is required. This study aimed to assess post-intervention effects of the Melbourne INFANT Program to child age 5y on diet, movement and adiposity. METHODS: Two and 3.5y post-intervention follow-up (2011-13; analyses completed 2019) of participants retained in the Melbourne INFANT Program at its conclusion (child age ~ 19 m; 2008-10) was conducted. The Melbourne INFANT Program is a 15-month, six session program delivered within first-time parent groups in Melbourne, Australia, between child age 4-19 m. It involves strategies to help parents promote healthy diet, physical activity and reduced sedentary behavior in their infants. No intervention was delivered during the follow-up period reported in this paper. At all time points height, weight and waist circumference were measured by researchers, children wore Actigraph and activPAL accelerometers for 8-days, mothers reported children's television viewing and use of health services. Children's dietary intake was reported by mothers in three unscheduled telephone-administered 24-h recalls. RESULTS: Of those retained at program conclusion (child age 18 m, n = 480; 89%), 361 families (75% retention) participated in the first follow-up (2y post-intervention; age 3.6y) and 337 (70% retention) in the second follow-up (3.5y post-intervention; age 5y). At 3.6y children in the intervention group had higher fruit (adjusted mean difference [MD] = 25.34 g; CI95:1.68,48.99), vegetable (MD = 19.41; CI95:3.15,35.67) and water intake (MD = 113.33; CI95:40.42,186.25), than controls. At 5y they consumed less non-core drinks (MD = -27.60; CI95:-54.58,-0.62). Sweet snack intake was lower for intervention children at both 3.6y (MD = -5.70; CI95:-9.75,-1.65) and 5y (MD = -6.84; CI95:-12.47,-1.21). Intervention group children viewed approximately 10 min/day less television than controls at both follow-ups, although the confidence intervals spanned zero (MD = -9.63; CI95:-30.79,11.53; MD = -11.34; CI95:-25.02,2.34, respectively). There was no evidence for effect on zBMI, waist circumference z-score or physical activity. CONCLUSIONS: The impact of this low-dose intervention delivered during infancy was still evident up to school commencement age for several targeted health behaviors but not adiposity. Some of these effects were only observed after the conclusion of the intervention, demonstrating the importance of long-term follow-up of interventions delivered during early childhood. TRIAL REGISTRATION: ISRCTN Register ISRCTN81847050 , registered 7th November 2007.

A systematic review of lifestyle patterns and their association with adiposity in children aged 5-12 years.

Diet, physical activity, sedentary behaviour and sleep are typically examined independently with childhood adiposity; however, their combined influence remains uncertain. This review aims to systematically summarize evidence on the clustering of these behaviours through lifestyle patterns and evaluate associations with adiposity in children aged 5-12 years. Search strategies were run in six databases. Twenty-eight papers met the inclusion criteria, six of which included all four behaviours. A range of lifestyle patterns were identified (healthy, unhealthy and mixed). Mixed patterns were most frequently reported. Unhealthy patterns comprising low physical activity and high sedentary behaviour were also frequently observed. Mixed patterns comprising healthy diets, low physical activity and high sedentary behaviour were more commonly seen in girls, whereas boys were more physically active, similarly sedentary and had unhealthier diets. Children from lower socio-economic backgrounds tended to more frequently display unhealthy patterns. Unhealthy lifestyle patterns were more often associated with adiposity risk than healthy and mixed patterns. With few studies including all four behaviours, it is difficult to establish a clear picture of their interplay and associations with adiposity. Nonetheless, reliance on lifestyle patterns is likely more beneficial than individual behaviours in targeting adiposity and improving understanding of how these behaviours influence health.

Prospective associations with physiological, psychosocial and educational outcomes of meeting Australian 24-Hour Movement Guidelines for the Early Years.

BACKGROUND: Several countries have released movement guidelines for children under 5 that incorporate guidelines for sleep, physical activity and sedentary behavior. This study examines prospective associations of preschool children's compliance with the 24-Hour Australian movement guidelines (sleep, physical activity, screen time) and physiological, psychosocial and educational outcomes during primary school. METHODS: Data were from the Healthy Active Preschool and Primary Years Study (Melbourne, Australia; n = 471; 3-5 years; 2008/9). Follow-ups occurred at 3 (2011/12; 6-8 years), 6 (2014/15; 9-11 years) and 7 (2016; 10-12 years) years post baseline. Multiple regression models assessed associations between compliance with guidelines at baseline and later outcomes. RESULTS: Children were 4.6 years at baseline (53% boys; 62% high socio-economic families). Most children met physical activity (89%) and sleep (93%) guidelines; 23% met screen-time guidelines; and 20% met all guidelines at baseline. Meeting all of the three guidelines was associated with lower BMI z-scores at 9-11 years of age (b = - 0.26, 95%CI -0.47, - 0.05). Meeting physical activity guidelines was associated with higher total body bone mineral density (b = 0.64, 95%CI 0.15, 1.13), and total body bone mineral content (b = 183.19, 95%CI 69.92, 296.46) at 10-12 years of age. Meeting sleep guidelines was associated with better reading (b = 37.60, 95%CI 6.74, 68.46), spelling (b = 34.95, 95%CI 6.65, 63.25), numeracy (b = 39.09, 95%CI 11.75, 66.44), language (b = 44.31, 95%CI 11.77, 76.85) and writing (b = 25.93, 95%CI 0.30, 51.57) at 8-9 years of age. No associations were evident for compliance with screen-time guidelines or for psychosocial outcomes. CONCLUSIONS: Compliance with different movement behavior guidelines was associated with different outcomes. Strategies to support children in meeting all of the guidelines are warranted to maximize health and educational outcomes. Future research investigating dose-response associations, and potential mechanisms, is necessary.

Lifestyle Patterns Begin in Early Childhood, Persist and Are Socioeconomically Patterned, Confirming the Importance of Early Life Interventions.

Traditional approaches to understanding the behavioural determinants of adiposity have considered diet, physical activity and sedentary behaviour in isolation. Although integrative approaches have identified a variety of lifestyle patterns in children at preschool-age or older, along with some variability by socio-economic positions, this has rarely been examined in younger cohorts. We aimed to identify lifestyle patterns at 1.5, 3.5 and 5 years, including dietary intake, outdoor time and television viewing time, to assess associations with maternal education (as a proxy for socio-economic position), and to investigate their persistence between toddlerhood and preschool age. Participants were 417 and 293 children aged 1.5 y from the Melbourne Infant Feeding Activity and Nutrition Trial (InFANT) and InFANT Extend Programs, respectively. Data were collected using questionnaires at child ages 1.5, 3.5 and 5 y (InFANT); and 1.5 and 3.5 y (InFANT Extend). Principal component analysis was undertaken at each time point on the separate and pooled datasets. Associations between the lifestyle patterns scores and maternal education were assessed with multivariable regression analysis. Two lifestyle patterns ("Discretionary consumption and TV" and "Fruit, vegetables and outdoor") were identified as early as 1.5 y. They remained consistent across ages and were evident in both datasets. These patterns were inversely and positively associated with maternal education, respectively. Such early clustering of obesity related energy balance behaviours and tracking during early childhood suggests there may be shared antecedents common to the individual behaviours that could be targeted for intervention. Our findings provide support for interventions targeting multiple behaviours and tailored to the level of family socio-economic disadvantage.

Joint physical-activity/screen-time trajectories during early childhood: socio-demographic predictors and consequences on health-related quality-of-life and socio-emotional outcomes.

BACKGROUND: Understanding the early roots of physical activity and sedentary behaviors is critical to developing intervention programs that promote healthy lifestyle habits in infants and children. There is, however, no evidence on how these behaviors cluster and develop together during early childhood. The aim of this study was to identify single and joint longitudinal trajectories in physical activity and screen time amongst children aged 0 to 9 years, their social-demographic predictors and their prospective health-related quality-of-life and socio-emotional outcomes. METHODS: Three waves of data from The Longitudinal Study of Australian Children, a national study tracking two cohorts every 2 years (B-cohort, 0-5 years, n = 4,164; K-cohort, 4-9 years, n = 3,974) were analysed. Growth mixture modelling was applied to longitudinal time-use diary data to identify joint trajectories in children's physical activity and screen time over Waves 1-3. Key socio-demographic variables measured at Wave 1 were used to predict membership in different trajectories. The prospective consequences (at Wave 3) of time-use trajectories on health-related quality-of-life and socio-emotional outcomes were assessed. RESULTS: Three physical-activity/screen-time trajectories were identified for both cohorts: Cluster-A-children who maintained low levels of physical activity and screen time (∽50% of the sample), Cluster-B-children who progressively increased physical activity and maintained low screen-time levels (∽25%), and Cluster-C-children who maintained low physical-activity levels and increased screen time (∽25%). Children in Cluster-B experienced the best health-related quality-of-life and socio-emotional outcomes, while those in Cluster-C experienced the worst. Children who were female, Indigenous, from non-English-speaking backgrounds, not living with two biological parents, in more affluent households and neighbourhoods, without siblings and with parents with poor mental health were at greater risk of falling into Cluster-A or Cluster-C. CONCLUSION: Our findings identified which children are most at-risk of falling into time-use trajectories that lead to poor health-related quality-of-life and socio-emotional outcomes later in life, increasing our ability to monitor, detect and prevent these suboptimal behaviours prior to their onset.

Paternal self-efficacy for promoting children's obesity protective diets and associations with children's dietary intakes.

OBJECTIVE: Fathers' parenting behaviours contribute to the development of children's dietary behaviours and subsequent weight outcomes, yet the majority of research focusses on maternal influences. Understanding fathers' perceptions of their effectiveness to influence children's dietary behaviours will allow the development of whole-of-family interventions promoting obesity protective behaviours. This unique study is the first to investigate 1) tracking of paternal self-efficacy for promoting obesity protective dietary intakes in young children; 2) demographic characteristics of fathers and their self-efficacy category; and 3) associations between paternal self-efficacy and young children's dietary intakes. METHODS: Paternal self-efficacy for promoting children's obesity protective dietary intakes was assessed longitudinally from fathers (n = 195) in the Extended Infant Feeding Activity and Nutrition Trial Program at child age 4 and 36 months. Multinomial logistic regression examined self-efficacy tracking categories (persistently high; persistently low; increasing; decreasing) by paternal age, education and BMI. Linear regression examined associations between paternal self-efficacy tracking categories and child dietary intakes at 36 months. RESULTS: Paternal self-efficacy for promoting children's obesity protective dietary intakes reduced over time. Fathers with trade/certificate or university qualifications had lower odds of having persistently low/decreasing self-efficacy (97 and 87% lower respectively) compared to high-school educated fathers. Positive associations (ß (95% CI)) were observed between paternal self-efficacy category and children's dietary intakes at 36 months: increasing self-efficacy and fruit (ß89.8 (6.8; 172.7)), and vegetables (ß39.2 (12.2; 66.2)); persistently high self-efficacy and water (ß69.1 (2.9; 135.1)); decreasing self-efficacy and non-core drinks ((ß30.1 (10.1; 50.1)). Persistently high self-efficacy was negatively associated with non-core drinks (ß-20.2 (- 34.8; - 5.5)), with negative associations observed between decreasing self-efficacy and children's intakes of fruit (ß - 49.9 (- 87.5; - 12.3)), vegetables (ß-19.9 (- 31.7; - 8.2)) and water (ß-92.4 (- 172.6; - 12.3)). CONCLUSIONS: Higher and/or sustained paternal self-efficacy is associated with fathers' education and is important in promoting children's obesity protective dietary intakes. Associations between paternal self-efficacy and children's dietary intakes are present at a young age. This investigation was unique in its focus on paternal self-efficacy for promoting children's obesity protective dietary intakes and associations with children's dietary intakes. Future family interventions should consider how to maintain and/or improve paternal self-efficacy to promote obesity protective intakes from early childhood.

Changes in volume and bouts of physical activity and sedentary time across early childhood: a longitudinal study.

BACKGROUND: Understanding changes in physical activity and sedentary time (SED) during early childhood may provide insights into how to effectively promote a healthy start to life. This study examined changes in total volume and bouts of SED, light- (LPA), and moderate- to vigorous-intensity physical activity (MVPA) across early childhood, and explored differences in change between boys and girls. METHODS: Data were drawn from 330 children participating in the Melbourne InFANT Program, collected between 2008 and 2013 and analysed in 2017. Children's physical activity and SED were assessed for at least 7 days at each timepoint using ActiGraph GT1M accelerometers at 19 months, 3.5 and 5 years of age. Total volume of SED (≤100 counts per minute [CPM]), LPA (101-1680 CPM) and MVPA (≥1681 CPM) were expressed as a percentage of wear time, and the frequency (number of bouts/day) and duration (mins/bout) of SED, LPA and MVPA bouts ≥1 min were calculated at each time point. Multilevel models with random intercepts and slopes were used to examine changes in total volume and bouts of SED, LPA and MVPA for boys and girls. RESULTS: Compared to aged 19 months, children's total volume of SED and LPA decreased at 3.5 and 5 years old, while MVPA increased. The frequency of SED bouts at 3.5 and 5 years was greater than at 19 months, but the duration was shorter. Additionally, the frequency and duration of LPA bouts was lower and MVPA bout frequency and duration was greater at 3.5 and 5 years. In general, there was no evidence of sex differences in trajectories of children's physical activity and SED. However, variations in trajectory were observed at the individual child level. CONCLUSIONS: Children's total volume and bouts of SED, LPA and MVPA change across early childhood, mostly in a favourable direction. Trajectories appear to be similar for boys and girls. Investigation of individual variation in trajectories is likely to provide greater insight into associations between physical activity and future health and behavioural outcomes.

Key Messages in an Early Childhood Obesity Prevention Intervention: Are They Recalled and Do They Impact Children's Behaviour?

Knowledge of the impact of health messages as an intervention strategy is sparse. The aim of this study was to explore recall and use of health behaviour messages among mothers, and whether recall is associated with child health behaviours. Intervention group data from the 15 months Melbourne Infant Feeding, Activity and Nutrition Trial (InFANT) were used (n = 127, children 4 months at commencement). Mothers recalled (unprompted then prompted) at 2 and 3.5 years post-intervention six key messages used in the program, and reported whether they had used them. Children's food intake was measured by three days of 24-h recall; physical activity by accelerometers; and television viewing by parent report. Unprompted recall ranged between 1-56% across messages and follow-up points, and 37-90% for prompted recall. The most commonly recalled messages "tap into water", "parents provide, kids decide" and "color every meal with fruit and veg" were also most commonly used. There were few associations between recall and children's health behaviours. Given the association between recall and reported use, it is important to plan messages so they resonate well with the target group and its needs. Messages should be used as one of multiple strategies within health promotion programs.

Role of parental and environmental characteristics in toddlers' physical activity and screen time: Bayesian analysis of structural equation models.

BACKGROUND: Guided by the Socialization Model of Child Behavior (SMCB), this cross-sectional study examined direct and indirect associations of parental cognitions and behavior, the home and neighborhood environment, and toddlers' personal attributes with toddlers' physical activity and screen time. METHODS: Participants included 193 toddlers (1.6 ± 0.2 years) from the Parents' Role in Establishing healthy Physical activity and Sedentary behavior habits (PREPS) project. Toddlers' screen time and personal attributes, physical activity- or screen time-specific parental cognitions and behaviors, and the home and neighborhood environment were measured via parental-report using the PREPS questionnaire. Accelerometry-measured physical activity was available in 123 toddlers. Bayesian estimation in structural equation modeling (SEM) using the Markov Chain Monte Carlo algorithm was performed to test an SMCB hypothesized model. Covariates included toddlers' age, sex, race/ethnicity, main type of childcare, and family household income. RESULTS: In the SMCB hypothesized screen time model, higher parental barrier self-efficacy for limiting toddlers' screen time was associated with higher parental screen time limiting practices (ß = 0.451), while higher parental negative outcome expectations for limiting toddlers' screen time was associated with lower parental screen time limiting practices (ß = - 0.147). In turn, higher parental screen time limiting practices was associated with lower screen time among toddlers (ß = - 0.179). Parental modeling of higher screen time was associated with higher screen time among toddlers directly (ß = 0.212) and indirectly through the home environment. Specifically, higher screen time among parents was associated with having at least one electronic device in toddlers' bedrooms (ß = 0.146) and, in turn, having electronics in the bedroom, compared to none, was associated with higher screen time among toddlers (ß = 0.250). Neighborhood safety was not associated with toddlers' screen time in the SEM analysis. No significant correlations were observed between the SMCB variables and toddlers' physical activity; thus, no further analyses were performed for physical activity. CONCLUSIONS: Parents and their interactions with the home environment may play an important role in shaping toddlers' screen time. Findings can inform family-based interventions aiming to minimize toddlers' screen time. Future research is needed to identify correlates of toddlers' physical activity.

Describing objectively measured physical activity levels, patterns, and correlates in a cross sectional sample of infants and toddlers from South Africa.

BACKGROUND: Physical activity is considered to have health benefits across the lifespan but levels, patterns, and correlates have not been well described in infants and toddlers under the age of two years. METHODS: This study aimed to describe objectively and subjectively measured physical activity in a group of South African infants aged 3- to 24-months (n = 140), and to investigate individual and maternal correlates of physical activity in this sample. Infants' physical activity was measured using an Axivity AX3 wrist-worn accelerometer for one week and the mean vector magnitude was calculated. In addition, mothers reported the average amount of time their infant spent in various types of activities (including in front of the TV), their beliefs about infants' physical activity, access to equipment in the home environment, and ages of motor development milestone attainment. Analysis of variance (ANOVA) and pair-wise correlations were used to test age and sex differences and associations with potential correlates. RESULTS: There were significant age and sex effects on the distribution of time spent at different physical activity intensities (Wilks' lambda = 0.06, p < 0.01). In all cases, the trend was for boys to spend more time in higher intensity physical activity and less time in lower intensity activity than girls; and for time spent in higher intensity activities to be higher in older children. Time spent outside was higher in boys, and this reached significance at 18-months (F = 3.84, p = 0.02). Less concern around floor play was associated with higher physical activity at 12-months in females only (p = 0.03, r = 0.54), and no other maternal beliefs were correlated with physical activity. The majority (94%) of children were exceeding TV time recommendations. When controlling for age and sex, overall TV time was positively associated with BMI z-score (ß=0.01, p = 0.05). CONCLUSION: This study is the first to show sex and age differences in the patterns of physical activity, and to report on objectively measured and maternal reported physical activity and sedentary behaviour in the first two years of life in South Africa infants. Infants and toddlers should be provided with as many opportunities to be active through play as possible, and TV time should be limited.