Genetic and environmental influences on human height from infancy through adulthood at different levels of parental education.

Genetic factors explain a major proportion of human height variation, but differences in mean stature have also been found between socio-economic categories suggesting a possible effect of environment. By utilizing a classical twin design which allows decomposing the variation of height into genetic and environmental components, we tested the hypothesis that environmental variation in height is greater in offspring of lower educated parents. Twin data from 29 cohorts including 65,978 complete twin pairs with information on height at ages 1 to 69 years and on parental education were pooled allowing the analyses at different ages and in three geographic-cultural regions (Europe, North America and Australia, and East Asia).

Epidemiological Transition in Physical Activity and Sedentary Time in Children.

Background: To determine if children's moderate to vigorous physical activity (MVPA) and sedentary time varied across levels of household income in countries at different levels of Human Development Index (HDI), consistent with the theory of epidemiological transition.

Methods: Data from 6548 children (55% girls) aged 9-11 years from 12 countries at different HDI levels are used in this analysis to assess MVPA and sedentary time (measured using ActiGraph accelerometers) across levels of household income. Least-square means are estimated separately for boys and girls at the estimated 10th, 50th, and 90th percentiles of HDI for the sample.

Parental Education and Genetics of BMI from Infancy to Old Age: A Pooled Analysis of 29 Twin Cohorts.

Objective: The objective of this study was to analyze how parental education modifies the genetic and environmental variances of BMI from infancy to old age in three geographic-cultural regions.

Methods: A pooled sample of 29 cohorts including 143,499 twin individuals with information on parental education and BMI from age 1 to 79 years (299,201 BMI measures) was analyzed by genetic twin modeling.

Results: Until 4 years of age, parental education was not consistently associated with BMI.

Tracking of gross motor coordination in Portuguese children.

The purpose of this study was to investigate the tracking of gross motor coordination (GMC) and to profile children at 6 years of age who consistently showed higher stability patterns in different levels of GMC. The participants were 245 children (123 boys and 122 girls) who were assessed longitudinally from 6 to 9 years of age. GMC was assessed using the Korperkoordinationtest fur Kinder (KTK) test battery.

Correlates of health-related quality of life in young-old and old-old community-dwelling older adults.

Purpose: This study aimed (1) to examine the role of potential correlates of HRQoL in a large representative sample of older adults, and (2) to investigate whether the relationships between HRQoL and potential factors differ as a function of HRQoL component (physical vs. mental) and/or age cohort (young-old vs. old-old).

Genetic and environmental effects on body mass index from infancy to the onset of adulthood: an individual-based pooled analysis of 45 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) study.

Background: Both genetic and environmental factors are known to affect body mass index (BMI), but detailed understanding of how their effects differ during childhood and adolescence is lacking.

Objectives: We analyzed the genetic and environmental contributions to BMI variation from infancy to early adulthood and the ways they differ by sex and geographic regions representing high (North America and Australia), moderate (Europe), and low levels (East Asia) of obesogenic environments.

Design: Data were available for 87,782 complete twin pairs from 0.

Genetic and environmental influences on height from infancy to early adulthood: An individual-based pooled analysis of 45 twin cohorts.

Height variation is known to be determined by both genetic and environmental factors, but a systematic description of how their influences differ by sex, age and global regions is lacking. We conducted an individual-based pooled analysis of 45 twin cohorts from 20 countries, including 180,520 paired measurements at ages 1-19 years. The proportion of height variation explained by shared environmental factors was greatest in early childhood, but these effects remained present until early adulthood.

The Oporto mixed-longitudinal growth, health and performance study. Design, methods and baseline results.

Background: Studies concerning child and adolescent growth, development, performance and health aimed at the multiple interactions amongst this complex set of variables are not common in the Portuguese speaking countries.

Aim: The aim of this paper is to address the key ideas, methodology and design of the Oporto Growth, Health and Performance Study (OGHPS).

Subjects And Methods: The OGHPS is a multidisciplinary mixed-longitudinal study whose main purpose is to examine the multiple interactions among biological, environmental and lifestyle indicators that affect growth, development, health and performance of Portuguese adolescents aged 10-18 years old.

Skeletal Muscle and Physical Activity in Portuguese Community-Dwelling Older Adults.

The aims of this study were to describe age- and sex-related differences in total body skeletal muscle (TB-SM) mass and to determine the variance explained by physical activity (PA). This cross-sectional study included 401 males and 402 females, aged 60-79 years. TB-SM was determined by dual-energy x-ray absorptiometry (DXA) and PA by Baecke questionnaire.

Developmental and physical-fitness associations with gross motor coordination problems in Peruvian children.

The aims of this cross-sectional study were to examine the developmental characteristics (biological maturation and body size) associated with gross motor coordination problems in 5193 Peruvian children (2787 girls) aged 6-14 years from different geographical locations, and to investigate how the probability that children suffer with gross motor coordination problems varies with physical fitness. Children with gross motor coordination problems were more likely to have lower flexibility and explosive strength levels, having adjusted for age, sex, maturation and study site. Older children were more likely to suffer from gross motor coordination problems, as were those with greater body mass index.

Skeletal Maturation, Body Size, and Motor Coordination in Youth 11-14 Years.

Purpose: The objective of this study is to estimate the relative contribution of biological maturation to variance in the motor coordination (MC) among youth and to explore gender differences in the associations.

Methods: Skeletal maturation (Tanner-Whitehouse 3), stature, body mass, and MC (Körperkoordinationstest für Kinder) were assessed in 613 youths, 284 boys and 329 girls 11-14 yr of age. Standardized residuals of skeletal age on chronological age were used as the estimate of skeletal maturity status independent of chronological age.

An evaluation of a nurse-led rehabilitation programme (the ProBalance Programme) to improve balance and reduce fall risk of community-dwelling older people: A randomised controlled trial.

Objective: This study aims to assess the effect of a nurse-led rehabilitation programme (the ProBalance Programme) on balance and fall risk of community-dwelling older people from Madeira Island, Portugal.

Design: Single-blind, randomised controlled trial.

Setting: University laboratory.

Relationship between physical activity, physical fitness and multiple metabolic risk in youths from Muzambinho's study.

Negative associations between physical activity (PA), physical fitness and multiple metabolic risk factors (MMRF) in youths from populations with low PA are reported. The persistence of this association in moderately-to highly active populations is not, however, well established. The aim of the present study was to investigate this association in a Brazilian city with high frequency of active youths.

Zygosity Differences in Height and Body Mass Index of Twins From Infancy to Old Age: A Study of the CODATwins Project.

A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years.

Variability and Stability in Daily Moderate-to-Vigorous Physical Activity among 10 Year Old Children.

Day-to-day variability and stability of children's physical activity levels across days of the week are not well understood. Our aims were to examine the day-to-day variability of moderate-to-vigorous physical activity (MVPA), to determine factors influencing the day-to-day variability of MVPA and to estimate stability of MVPA in children. The sample comprises 686 Portuguese children (10 years of age).

Sex-specific genetic effects in physical activity: results from a quantitative genetic analysis.

Background: The objective of this study is to present a model to estimate sex-specific genetic effects on physical activity (PA) levels and sedentary behaviour (SB) using three generation families.

Methods: The sample consisted of 100 families covering three generations from Portugal. PA and SB were assessed via the International Physical Activity Questionnaire short form (IPAQ-SF).

Why Are Children Different in Their Daily Sedentariness? An Approach Based on the Mixed-Effects Location Scale Model.

This study aimed to investigate the between- and within-individual variability in sedentary time over seven days, using a mixed-effects location scale model. The sample comprised 686 Portuguese children (381 girls) aged 9-11 years, from 23 schools. Sedentary time was estimated by the Actigraph GT3X+ accelerometer, which was used 24 hours/day for 7 consecutive days; height, sitting height, and weight were measured, BMI was computed (WHO cut-points were used to classify subjects as normal weight or overweight/obese), and maturity offset was estimated.

Change, stability and prediction of gross motor co-ordination in Portuguese children.

Background: The knowledge about intra- and inter-individual variation can stimulate attempts at description, interpretation and prediction of motor co-ordination (MC).

Aim: To analyse change, stability and prediction of motor co-ordination (MC) in children.

Subjects And Methods: A total of 158 children, 83 boys and 75 girls, aged 6, 7 and 8 years, were evaluated in 2006 and re-evaluated in 2012 at 12, 13 and 14 years of age.

Differences in motor performance between children and adolescents in Mozambique and Portugal: impact of allometric scaling.

Background: Children from developed and developing countries have different anthropometric characteristics which may affect their motor performance (MP).

Aim: To use the allometric approach to model the relationship between body size and MP in youth from two countries differing in socio-economic status-Portugal and Mozambique.

Subjects And Methods: A total of 2946 subjects, 1280 Mozambicans (688 girls) and 1666 Portuguese (826 girls), aged 10-15 years were sampled.

Profiling physical activity, diet, screen and sleep habits in Portuguese children.

Obesity in children is partly due to unhealthy lifestyle behaviours, e.g., sedentary activity and poor dietary choices.

The CODATwins Project: The Cohort Description of Collaborative Project of Development of Anthropometrical Measures in Twins to Study Macro-Environmental Variation in Genetic and Environmental Effects on Anthropometric Traits.

For over 100 years, the genetics of human anthropometric traits has attracted scientific interest. In particular, height and body mass index (BMI, calculated as kg/m2) have been under intensive genetic research. However, it is still largely unknown whether and how heritability estimates vary between human populations.

Gross motor coordination and weight status of Portuguese children aged 6-14 years.

Objectives: To construct age- and gender-specific percentiles for gross motor coordination (MC) tests and to explore differences in gross MC in normal-weight, overweight and obese children.

Methods: Data are from the "Healthy Growth of Madeira Study," a cross-sectional study carried out in children, aged 6-14 years. All 1,276 participants, 619 boys and 657 girls, were assessed for gross MC (Körperkoordinations Test für Kinder, KTK), anthropometry (height and body mass), physical activity (Baecke questionnaire) and socioeconomic status (SES).

Skeletal maturation, fundamental motor skills and motor coordination in children 7-10 years.

Relationships between skeletal maturation and fundamental motor skills and gross motor coordination were evaluated in 429 children (213 boys and 216 girls) 7-10 years. Skeletal age was assessed (Tanner-Whitehouse 2 method), and stature, body mass, motor coordination (Körperkoordinations Test für Kinder, KTK) and fundamental motor skills (Test of Gross Motor Development, TGMD-2) were measured. Relationships among chronological age, skeletal age (expressed as the standardised residual of skeletal age on chronological age) and body size and fundamental motor skills and motor coordination were analysed with hierarchical multiple regression.

Birthweight, body composition, and motor performance in 7- to 10-year-old children.

Aim: The aim of this study was to analyse the influence of birthweight on motor performance and body composition in children. Further, we investigated whether associations between birthweight and motor performance changed after adjustment for current height, body mass index (BMI), fat-free mass (FFM), and % body fat.

Method: A total of 483 children (251 males and 232 females) aged 7 to 10 years (mean 8.