Exploring the relationship between adolescent biological maturation, physical activity, and sedentary behaviour: A systematic review and narrative synthesis

Context: Across adolescence, there is a notable decline in physical activity in boys and girls. Maturational timing may be a risk factor for disengagement from physical activity and increased sedentary behaviours during adolescence. Objective: This systematic review aimed to summarise literature that examined the relationship between maturational timing, physical activity and sedentary behaviour in adolescents. Methods: Six electronic databases were searched for articles that assessed biological maturation and physical activity (including sports participation and active transportation) or sedentary behaviours in adolescents. Two reviewers conducted title, abstract, and full-text screening, reference and forward citation searches. Included articles were evaluated for quality using a standardised tool. A narrative synthesis was used to analyse the findings due to the heterogeneity of the studies. Results: Searches yielded 78 articles (64 unique studies) that met the inclusion criteria, representing 242,316 participants (153,179 unique). Studies ranged from 30.0% (low) to 91.7% (high) in quality. An inverse relationship between maturational timing and physical activity (in 50 and 60% of studies in boys and girls, respectively) and a positive relationship between maturational timing and sedentary behaviour (in 100% and 53% of studies in boys and girls, respectively) was most commonly reported. Evidence supporting an association between maturational timing, sports participation, and active transportation was inconsistent. Conclusions: While this review demonstrates some evidence for early maturational timing as a risk factor for disengagement from physical activity and increase in sedentary behaviours, the reviewed literature also demonstrates that this relationship is complex. Future research that tracks maturity-related variations in physical activity and sedentary behaviours over adolescence is warranted

The Portuguese Sibling Study on Growth, Fitness, Lifestyle and Health.

Esta tese pretendeu descrever e interpretar a teia relacional entre fatores individuais, familiares e ambientais na forma do corpo, composição corporal, aptidão física, síndrome metabólica e estilos de vida em pares de irmãos. Amostraram-se 1583 pares de irmãos com idades compreendidas entre 9 e 20 anos; 202 pares foram seguidos durante três anos consecutivos. As variáveis utilizadas foram colhidas com protocolos estandardizados e a informação obtida foi hierarquicamente distribuída por três domínios: individual, familiar e ambiental. Os procedimentos estatísticos recorreram aos softwares SPSS, Somatotype calculation, Mplus, MIXREGLS, Supermix e STATA. Os resultados mostraram que: (1) a semelhança fraterna é maior nos irmãos do mesmo sexo comparativamente com os irmãos do sexo oposto; (2) um índice familiar de magnitude moderado foi observado no somatótipo e na agregação de marcadores de saúde (MS); (3) os fatores individuais e familiares influenciaram, em diferentes magnitudes, as características em análise. Porém, a idade cronológica, a maturação biológica e a aptidão física (AptF) associaram-se com todos os fenótipos; (4) as características ambientais relacionaram-se com a variação nos fenótipos; (5) emergiram dois perfis de MS sendo o mais prevalente (86.7%) caracterizado por menores valores de percentagem de gordura, maiores níveis de AptF e maiores scores de dieta não saudável; (6) apenas a profissão e habilitações literárias do pai associaram-se à pertença aos perfis; (7) os valores de tracking individual são mais elevados nos marcadores de obesidade comparativamente com as componentes de AptF; (8) todos os tipos de pares tendem a ser consistentes nas suas trajetórias dos marcadores de obesidade, mas nas componentes de AptF são as irmãs que se mostraram mais consistentes; (9) os estilos de vida e as características ambientais influenciam os marcadores de obesidade. Contudo, nas componentes de AptF são as características biológicas que mais afetam as suas trajetórias. Esta tese destacou um conjunto de questões e sugestões que devem ser consideradas aquando da elaboração de programas que visem a promoção de saúde em crianças e adolescentes. PALAVRAS-CHAVE: IRMÃOS, SOMATÓTIPO, ATIVIDADE FÍSICA, MARCADORES DE SAÚDE, SINDROME METABÓLICAThis thesis aimed to describe and interpret the network of relations between individual, familial and environmental factors in their body shape and composition, physical fitness, metabolic syndrome and lifestyle behaviours in sibling pairs. We sampled 1583 sibling pairs aged 9 to 20 years; 202 pairs were consecutively followed for three years. All data was collected using standardized protocols and the information was distributed over three nested domains: individual, family and environmental. Statistical procedures were done in SPSS, Somatotype calculation, Mplus, MIXREGLS, Supermix and STATA software. Results showed that: (1) fraternal similarity is greater in same-sex siblings compared to the opposite sex siblings; (2) A familial index of moderate magnitude was observed in the somatotype and in the clustering of health markers (HM); (3) individual and family factors differently associated with traits under scrutiny with different effect-sizes. However, chronological age, biological maturation and physical fitness (PF) associated with all phenotypes; (4) environmental characteristics were related with phenotype´s variation; (5) two HM profiles emerged: the most prevalent (86.7%) was characterized by lower values of percentage body fat, higher PF levels and higher unhealthy diet scores; (6) only father's occupation and educational qualifications were associated with membership in these two profiles; (7) individual tracking was higher in obesity markers compared to PF components; (8) all types of pairs tend to be consistent in their trajectories of obesity markers; however, in PF components sisters were more consistent; (9) lifestyle behaviours and environmental characteristics influenced obesity markers; however, in the PF components, were the biological characteristics that most affected sibling's trajectories. This thesis highlighted a set of issues and suggestions that need to be considered when designing health promotion programs in children and adolescents

A Systematic Analysis Of Temporal Trends In The Sit-Ups Performance Of 9,939,289 Children And Adolescents Between 1964 And 2017 Representing 31 Countries

Objective: To estimate national and international temporal trends in the sit-ups performance of children and adolescents, and to examine relationships between trends in sit-ups performance and trends in health-related and sociodemographic indicators. Methods: Data were obtained in three ways: (a) through a systematic electronic database search of studies reporting on temporal trends in the handgrip strength of apparently healthy 9–17 year-olds, (b) by pearling reference lists, topical systematic reviews and personal libraries, and (c) by examining large country-level fitness datasets suitable to temporal trends analysis. Sample-weighted temporal trends (expressed as percent and standardized trends) were estimated at the country-sex-age level using best-fitting regression models relating the year of testing to mean sit-ups performance. International and national trends were estimated by post-stratified population-weighted mean changes standardized to the year 2000. Pearson’s correlations were used to quantify relationships between linear trends in sit-ups performance and linear trends in health-related and sociodemographic indicators. Results: Trend data from 27 studies/datasets representing 9,939,289 children and adolescents representing 31 countries (25 high-, 5 upper-middle-, and 1 low-income countries) between 1964 and 2017 collectively showed a large improvement in mean sit- ups performance of 38.4% (95%CI: 36.8 to 40.0) or 7.1% per decade (95%CI: 6.8 to 7.4). Large international improvements were experienced by all age and sex groups, with the rate of improvement slowing from 1964 to 2000, stabilizing near zero until 2010, before declining thereafter. Trends differed in magnitude and direction between countries, with most experiencing improvements. Trends in vigorous physical activity levels were a strong positive correlate of trends in sit-ups performance. Conclusions: There has been a large international improvement in children’s sit-ups performance since 1967, which has progressively diminished in magnitude over time. Sit- ups data are needed from children in low-income and middle-income countries in order to better monitor national and international trends in muscular fitness

Being Normal Weight but Feeling Overweight in Adolescence May Affect Weight Development into Young Adulthood—An 11-Year Followup: The HUNT Study, Norway

Objectives. To explore if self-perceived overweight in normal weight adolescents influence their weight development into young adulthood and if so, whether physical activity moderates this association. Methods. A longitudinal study of 1196 normal weight adolescents (13–19 yrs) who were followed up as young adults (24–30 yrs) in the HUNT study. Lifestyle and health issues were assessed employing questionnaires, and standardized anthropometric measurements were taken. Chi square calculations and regression analyses were performed to investigate the associations between self-perceived overweight and change in BMI or waist circumference (WC) adjusted for age, age squared, sex, and other relevant cofactors. Results. Adolescents, defined as being normal weight, but who perceived themselves as overweight had a larger weight gain into young adulthood than adolescents who perceived themselves as normal weight (difference in BMI: 0.66 units [CI95%: 0.1, 1.2] and in WC: 3.46 cm [CI95%: 1.8, 5.1]). Level of physical activity was not found to moderate this association. Conclusions. This study reveals that self-perceived overweight during adolescence may affect development of weight from adolescence into young adulthood. This highlights the importance of also focusing on body image in public health interventions against obesity, favouring a “healthy” body weight taking into account natural differences in body shapes

Abdominal obesity and low physical activity are associated with insulin resistance in overweight adolescents: a cross-sectional study

ABSTRACT: Background: Previous studies have assessed the metabolic changes and lifestyles associated with overweight adolescents. However, these associations are unclear amongst overweight adolescents who have already developed insulin resistance. This study assessed the associations between insulin resistance and anthropometric, metabolic, inflammatory, food consumption, and physical activity variables amongst overweight adolescents. Methods: This cross-sectional study divided adolescents (n = 120) between 10 and 18 years old into 3 groups: an overweight group with insulin resistance (O + IR), an overweight group without insulin resistance (O-IR), and a normal-weight control group (NW). Adolescents were matched across groups based on age, sex, pubertal maturation, and socioeconomic strata. Anthropometric, biochemical, physical activity, and food consumption variables were assessed. Insulin resistance was assessed using homeostatic model assessment (HOMA Calculator Version 2.2.2 from ©Diabetes Trials Unit, University of Oxford), and overweight status was assessed using body mass index according to World Health Organization (2007) references. A chi-square test was used to compare categorical variables. ANOVAs or Kruskal-Wallis tests were used for continuous variables. Multiple linear regression models were used to calculate the probability of the occurrence of insulin resistance based on the independent variables. Results: The risk of insulin resistance amongst overweight adolescents increases significantly when they reach a waist circumference > p95 (OR = 1.9, CIs = 1.3-2.7, p = 0.013) and watch 3 or more hours/day of television (OR = 1.7, CIs = 0.98-2.8, p = 0.033). Overweight status and insulin resistance were associated with higher levels of inflammation (hsCRP ≥1 mg/L) and cardiovascular risk according to arterial indices. With each cm increase in waist circumference, the HOMA index increased by 0.082; with each metabolic equivalent (MET) unit increase in physical activity, the HOMA index decreased by 0.026. Conclusions: Sedentary behaviour and a waist circumference > p90 amongst overweight adolescents were associated with insulin resistance, lipid profile alterations, and higher inflammatory states. A screening that includes body mass index, in waist circumference, and physical activity evaluations of adolescents might enable the early detection of these alterations

Eveningness associates with lower physical activity from pre- to late adolescence

Objective: Adolescence is often associated with decline in physical activity (PA) and a circadian shift towards eveningness, but it is not known whether these transitions are intertwined. We explored longitudinally and in cross-section how chronotype and genetic liability for morningness associate with PA as self-reported and measured by actigraphy in early and late adolescence. Methods: Our sample comes from a longitudinal Finnish community-cohort born in 1998 with information on actigraph-based PA and objectively measured sleep-wake rhythm based on midpoint of sleep at ages 12 (N = 353, girls = 187) and 17 (N = 171, girls = 98). Information on self-reported circadian preference and subjective PA was available at age 17. The summarized genetic effects of multiple single nucleotide polymorphism for morningness was assessed by calculating polygenic score (PGS) based on the results on a recent genome-wide association study (GWAS). Results: PA declined by 40% (p = 0.36). However, those with circadian preference more towards eveningness at age 17 had more sedentary behavior (p <0.01) and a lower level of general (p = 0.01), light (p <0.01) and moderate to vigorous PA (p <0.05). They also had poorer subjective assessment of their fitness level (p <0.01) and they exercised less (all p = 0.13). Conclusions: Findings of this study highlighted the influence of circadian preference on physical activity behavior in adolescence. Self-assessed circadian preference towards eveningness associated with lower PA and greater decline of it during adolescence. Furthermore, PA declined significantly especially among boys from early to late adolescence. Interventions encouraging physical activity should target specifically evening-oriented adolescents. (C) 2020 Elsevier B.V. All rights reserved.Peer reviewe

Physical Activity in High School Classrooms: A Promising Avenue for Future Research

Adolescence represents a sensitive period whereby lifestyle factors such as physical activity can have profound, long-lasting effects on development and later life habits. However, adolescence constitutes a period of frequent sedentary behaviour. Among children, integrating physical activity into elementary school classrooms has been shown to reduce sedentary behaviour and improve academic achievement and overall physical and mental health. However, this promising area of research has not extended to adolescents and high school classrooms. In this paper, we describe the benefits of conducting research on the impact of physically active high school classrooms, and highlight the challenges and potential misconceptions associated with research in this field. Specifically, we review research on the role of physical activity in adolescent development, the benefits of classroom-based physical activity for children, and discuss the factors that may have led researchers to focus on classroom-based physical activity primarily for children, despite the potentially similar benefits for adolescents

Children’s Fitness and Quality of Movement

Introduction: Movement is essential to life and plays a key role in development throughout childhood. Movement can be assessed by its quantity and quality. Movement is important to measure as it can aid early intervention. Current research suggests that global levels of fitness are declining, with a lack of research surrounding children’s natural fitness levels as they get older. Quantity of movement is commonly studied, however quality is becoming increasingly popular. A clear understanding of the methods of technology used to measure quality of movement is important as understanding this area will aid in designing appropriate interventions.Methods: This thesis comprises of two experimental studies. Study one is a repeated measures design using previously collected Swanlinx data to investigate how components of children’s fitness change over a one-year period. Study two is a scoping review investigating the measurement of quality of movement with technology in the form of MEM’s devices, while aiming to gain clarity on the definition of quality.Results: Study one revealed that children’s fitness levels increase across a one-year period, in all components of fitness, except sit and reach. Boys performed significantly better in all fitness components, apart from sit and reach. Study two demonstrated the broad field that is included under the term of quality, showing clarity is needed in this area. A large number of devices, movements and populations are being observed, with multiple definitions of quality which is dependent on the metrics collected.Conclusion: Study one concludes that children’s fitness levels increase over one-year, with boys performing better than girls. This can be used to understand children’s natural fitness levels and aid future interventions in participation. Study two concludes that there are multiple ways to assess quality of movement however a clear definition of the quality should be stated, aiding comparison of quality

Evaluating the developmental trajectories of fundamental movement skills across late childhood and adolescence

The association between physical inactivity and many non-communicable diseases is now well established. Physical activity is a complex and multidimensional behaviour, with proficiency in fundamental movement skills (FMS) recognised as a key correlate of increased physical activity levels, as well as being positively associated with further health outcomes. As children transition into adolescence, the mechanisms determining physical activity levels appear to become less understood. Therefore, the overarching aim of this thesis was to investigate the development of FMS, and their association with psychological, behavioural, and cognitive factors, in late childhood and adolescence. Study 1 examined the role of sex in moderating the association of FMS and health and behavioural outcomes in late childhood. The results highlighted the sex-specific development and role of FMS in children transitioning into secondary-level education, and who therefore represent a crucial developmental stage. Subsequently, Study 2 investigated the influence of biological maturation and other moderators on specific performance characteristics of FMS. Given the importance of ensuring validity in the assessment of FMS, Study 2 revealed the risks associated with using a single assessment method, especially in pre-pubertal children. The level of agreement between assessment methods (process- and product-oriented) was highest in post-pubertal children and, as such, practitioners can be more confident when adopting a single assessment approach in this group. Study 3 aimed to identify the association of skill competence, sex, and increasing maturity with the energy expenditure (EE) associated with performing FMS, highlighting the potential health-enhancing benefits associated with achieving proficiency in FMS. From an interventional perspective, the findings of Study 3 reinforce the contribution of FMS towards both direct (i.e. associated EE) and indirect health-enhancing benefits (i.e. physical activity, weight status, health-related fitness). There is a vast array of evidence pertaining to the association between motor competence and cognitive and social-emotional outcomes in childhood, yet many studies have approached this relationship in isolation. To guide future research, Study 4 presented a conceptual model where underpinning mechanisms of the relationship between motor competence and cognitive and social-emotional outcomes are hypothesised. Moreover, Study 4 synthesised current evidence relating to the influence of FMS on cognitive and social-emotional outcomes, which was subsequently explored in Study 5. In Study 5 the moderated association of FMS and aspects of academic attainment in adolescence were investigated, revealing a key association between object control skills and academic attainment. The results of this study advocate that FMS should remain a key strategic aim in adolescent physical activity interventions and should be integrated within curriculum design as a mechanism for improving academic attainment. Overall, this thesis demonstrates the continued importance of FMS to a range of health-related and cognitive outcomes during adolescence. Recognising that children are now consistently beginning secondary-level education without proficiency in FMS warrants increased attention is directed towards gaining a better understanding of how we can intervene and approach the development of FMS in a supportive environment

Physical Activity, Wellness and Health: Challenges, Benefits and Strategies

Regular physical activity (PA) is both a preventive measure and a cure for non-communicable diseases. Moreover, PA improves mental health, quality of life, and well-being. Conversely, physical inactivity and sedentary lifestyles have negative impacts on individuals, families, and society, as evidenced in particular by the spread of the obesity epidemic. PA has proven to be a low-cost alternative for the treatment and prevention of disease. Therefore, interventions to prevent avoidable diseases by increasing the proportion of physically active people are fundamental. The Special Issue “Physical Activity, Wellness and Health: Challenges, Benefits and Strategies” was collected research articles on anthropometric determinants of health and performance, PA and healthy habits, exercise and diet, exercise and body composition, interventions to promote PA for people of all ages, strategies for the implementation of an active life, and the beneficial effects of exercise on metabolic syndrome. A total of 20 articles were published, falling mainly into the following three areas: anthropometry, health, and sport; health benefits of exercise; population studies and strategies for an active life. All of the studies support strategies to promote PA and reduce sedentary behavior among adolescents, adults and the elderly. There is no doubt that regular exercise is beneficial to health, but the general population should be encouraged to engage in more of it