Sedentary behaviors and adiposity in young people: causality and conceptual model

Research on sedentary behavior and adiposity in youth dates back to the 1980s. Sedentary behaviors, usually screen time, can be associated with adiposity. Although the association usually is small but significant, the field is complex, and results are dependent on what sedentary behaviors are assessed and may be mediated and moderated by other behaviors

Interventions designed to reduce sedentary behaviours in young people: A review of reviews

Background: Leisure time is increasingly spent in sedentary pursuits such as screen-viewing (eg, television/DVD viewing and computer use), motorised travel, school/work and sitting-based socialising (eg, social media and chatting). Sedentary screen time, particularly TV, appears to play an important role in the aetiology of obesity due to its co-occurrence with other unhealthy behaviours such as snacking on energy-dense foods, low levels of physical activity and inadequate sleep. More information is needed on how to reduce sedentary behaviours. Most interventions have focused on young people and a number of systematic reviews exist on this topic. Objective: To synthesise systematic reviews and metaanalyses of interventions aimed at decreasing sedentary behaviours among children and adolescents. Methods: Papers were located from computerised and manual searches. Included articles were English language systematic reviews or meta-analyses of interventions aiming at reducing sedentary behaviour in children (<11 years) and adolescents (12-18 years). Results: Ten papers met the inclusion criteria and were analysed. All reviews concluded some level of effectiveness in reducing time spent in sedentary behaviour. When an effect size was reported, there was a small but significant reduction in sedentary time (highest effect size=-0.29; CI -0.35 to -0.22). Moderator analyses showed a trend favouring interventions with children younger than 6 years. Effective strategies include the involvement of family, behavioural interventions and electronic TV monitoring devices. Conclusions: Results from systematic reviews and meta-analyses show that interventions to reduce children's sedentary behaviour have a small but significant effect. Future research should expand these findings examining interventions targeting different types of sedentary behaviours and the effectiveness of specific behaviour change techniques across different contexts and settings

Behavioural nutrition and physical activity in young people : the role of the family

The increasing evidence of associations between inactivity and poor diets in young people and both immediate and long term health implications is of public health concern. There is a need to further understanding of young people's health behaviours, to facilitate the development of behaviour change strategies promoting healthy behaviours. This thesis, provides seven studies focusing on the family environment and the influences that the family and parents have on young people's physical activity and dietary behaviours. Chapter 2.1 describes a systematic review of family correlates of fruit and vegetable consumption in children and adolescents. Chapter 2.2 describes a systematic review of family correlates of breakfast consumption among children and adolescents. Systematic reviews are an essential component of evidence-based practice, and both reviews were conducted to examine the state of the current literature examining family environmental influences on aspects of young people's dietary behaviours. In the context of this thesis, these systematic reviews are of primary importance as they were instrumental in shaping and informing the direction of the research described in later chapters. Chapter 3 broadens the investigation of young people's health behaviours and describes two cross-sectional studies examining both physical activity and dietary behaviours. Chapter 3.1 describes a study examining patterns of adolescent physical activity and dietary behaviours. This study describes how adolescents are at risk of not meeting the recommendations for multiple health behaviours (e.g. physical activity, fruit and vegetable consumption, and breakfast consumption). Chapter 3.2 was designed to fill several gaps in the literature about the correlates of multiple health behaviours and also to gain a greater insight into the transferability of parental behaviours to different health behaviours in children. Chapter 3.2 describes a study examining family influences on young peoples fruit and vegetable consumption and physical activity, and on combinations of these behaviours (e.g. high physical activity and low fruit and vegetable consumption). Chapter 4.1 was designed to fill gaps in the literature by examining the association between family circumstance (parental marital status, maternal education, maternal employment status, number of brothers and number of sisters) and adolescent dietary behaviour, and 2-year change in dietary behaviour. Chapter 4.2 was designed to fill gaps in the literature by examining the relationship between parenting styles, family structure and aspects of adolescent dietary behaviour. Together, the six studies described above established a rationale and informed the content of the pilot family-based intervention described in Chapter 5. This thesis found that particular aspects of the family environment and particular attributes of parenting were associated with positive physical activity and dietary behaviours of young people. Such findings add considerably to the existing literature and are important as they suggest that even as young people age, the family environment and the emotional context within which parent-child interactions occur are vital for positive health behaviours. Targeting such facets of the family and parenting holds great potential for behaviour change strategies.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Are parental concerns for child TV viewing associated with child TV viewing and the home sedentary environment?

BackgroundTime spent watching television affects multiple aspects of child and adolescent health. Although a diverse range of factors have been found to be associated with young people\u27s television viewing, parents and the home environment are particularly influential. However, little is known about whether parents, particularly those who are concerned about their child\u27s television viewing habits, translate their concern into action by providing supportive home environments (e.g. rules restricting screen-time behaviours, limited access to screen-based media). The aim of this study was to examine associations between parental concerns for child television viewing and child television viewing and the home sedentary environment.MethodsParents of children aged 5-6 years (\u27younger\u27 children, n = 430) and 10-12 years (\u27older children\u27, n = 640) reported usual duration of their child\u27s television (TV) viewing, their concerns regarding the amount of time their child spends watching TV, and on aspects of the home environment. Regression analyses examined associations between parental concern and child TV viewing, and between parental concern and aspects of the home environment. Analyses were stratified by age group.ResultsChildren of concerned parents watched more TV than those whose parents were not concerned (B = 9.63, 95% CI = 1.58-17.68, p = 0.02 and B = 15.82, 95% CI = 8.85-22.80, p &lt; 0.01, for younger and older children respectively). Parental concern was positively associated with younger children eating dinner in front of the television, and with parental restriction of sedentary behaviours and offering sedentary activities (i.e. TV viewing or computer use) as a reward for good behaviour among older and young children. Furthermore, parents of older children who were concerned had fewer televisions in the home and a lower count of sedentary equipment in the home.ConclusionsChildren of concerned parents watched more TV than those whose parents who were not concerned. Parents appear to recognise excessive television viewing in their children and these parents appear to engage in conflicting parental approaches despite these concerns. Interventions targeting concerned parents may be an innovative way of reaching children most in need of strategies to reduce their television viewing and harnessing this parental concern may offer considerable opportunity to change the family and home environment.<br /

The effectiveness of interventions to increase physical activity among adolescent girls: A meta-analysis

Background Research has shown that a clear decline in physical activity among girls starting in early adolescence. Therefore, adolescent girls have been identified as a key target population for physical activity behavior change. The quantification of intervention effectiveness for this group has not been previously reported in a meta-analysis, and this therefore was the objective of the current meta-analysis. Study Selection Included were interventions in which the main component, or 1 of the components, was aimed at promoting physical activity through behavior change in any setting. Interventions had to include a non–physical activity control group or comparison group, and include a quantitative outcome assessment of physical activity behavior in girls aged 12 to 18 years. Data Sources Science Direct, PubMed, PsychINFO, Web of Science, Cochrane Libraries, and EPPI Centre databases were searched up to and including May 2013. Data Extraction and Synthesis Forty-five studies (k = 34 independent samples) were eligible from an initial 13,747 references. A random-effects meta-analysis was conducted. Results The average treatment effect for adolescent girls involved in physical activity interventions was significant but small (g = 0.350, 95% confidence interval 0.12, 0.58, P < .001). Moderator analyses showed larger effects for interventions that were theory based, performed in schools, were girls only, with younger girls, used multicomponent strategies, and involved targeting both physical activity and sedentary behavior. Conclusions Interventions to increase physical activity in adolescent girls show small but significant effects, suggesting that behavior change may be challenging. Results suggest some approaches that appear to be successful

An assessment of self-reported physical activity instruments in young people for population surveillance: Project ALPHA

<p>Abstract</p> <p>Background</p> <p>The assessment of physical activity is an essential part of understanding patterns and influences of behaviour, designing interventions, and undertaking population surveillance and monitoring, but it is particularly problematic when using self-report instruments with young people. This study reviewed available self-report physical activity instruments developed for use with children and adolescents to assess their suitability and feasibility for use in population surveillance systems, particularly in Europe.</p> <p>Methods</p> <p>Systematic searches and review, supplemented by expert panel assessment.</p> <p>Results</p> <p>Papers (n = 437) were assessed as potentially relevant; 89 physical activity measures were identified with 20 activity-based measures receiving detailed assessment. Three received support from the majority of the expert group: Physical Activity Questionnaire for Children/Adolescents (PAQ-C/PAQ-A), Youth Risk Behaviour Surveillance Survey (YRBS), and the Teen Health Survey.</p> <p>Conclusions</p> <p>Population surveillance of youth physical activity is strongly recommended and those involved in developing and undertaking this task should consider the three identified shortlisted instruments and evaluate their appropriateness for application within their national context. Further development and testing of measures suitable for population surveillance with young people is required.</p

Family influences on children's physical activity and fruit and vegetable consumption

Background : There is evidence of a clustering of healthy dietary patterns and physical activity among young people and also of unhealthy behaviours. The identification of influences on children\u27s health behaviors, particularly clustered health behaviors, at the time at which they develop is imperative for the design of interventions. This study examines associations between parental modelling and support and children\u27s physical activity (PA) and consumption of fruit and vegetables (FV), and combinations of these behaviours.Methods : In 2002/3 parents of 775 Australian children aged 10&ndash;12 years reported how frequently their child ate a variety of fruits and vegetables in the last week. Children wore accelerometers for eight days during waking hours. Parental modelling and parental support (financial and transport) were self-reported. Binary logistic and multinomial logistic regression analyses examined the likelihood of achieving &ge; 2 hours of PA per day (high PA) and of consuming &ge; 5 portions of FV per day (high FV) and combinations of these behaviors (e.g. high PA/low FV), according to parental modelling and support.Results : Items of parental modelling and support were differentially associated with child behaviours. For example, girls whose parents reported high PA modelling had higher odds of consuming &ge; 5 portions of FV/day (OR = 1.95, 95% CI = 1.32&ndash;2.87, p &lt; 0.001). Boys whose parents reported high financial support for snacks/fast foods had higher odds of having \u27high PA/low FV\u27 (OR = 2.0, 95% CI = 1.1&ndash;3.7).Conclusion : Parental modelling of and support for physical activity and fruit and vegetable consumption were differentially associated with these behaviours in children across behavioural domains and with combinations of these behaviours. Promoting parents\u27 own healthy eating and physical activity behaviours as well encouraging parental modelling and support of these behaviours in their children may be important strategies to test in future research.<br /

Probabilistic flood forecasting

The Environment Agency provides a forecasting and warning service to people at risk from flooding. However, flood forecasts are inherently un- certain. Efforts to quantify the uncertainty based on quantile regression have failed to capture the full extent of the uncertainty associated with significant flooding events. An investigation into factors that may be correlated with the uncertainty lead to the observation that there are structural biases in the model. It is possible to remove these, and thereby reduce the mean square error of the predictions, but the benefit of this is apparent in the prediction of ’normal’ conditions, rather than in flood predictions. Additionally, a tweak to the linear fit in the quantile regression is sug- gested which is better suited to the data