Luis Paulo Rodrigues

Motor coordination as predictor of physical activity in childhood

This study considers relationships among motor coordination (MC), physical fitness (PF) and physical activity (PA) in children followed longitudinally from 6 to 10 years. It is hypothesized that MC is a significant and primary predictor of PA in children. Subjects were 142 girls and 143 boys. Height, weight and skinfolds; PA (Godin–Shephard questionnaire); MC (Körperkoordination Test für Kinder); and PF (five fitness items) were measured. Hierarchical linear modeling with MC and PF as predictors of PA was used. The retained model indicated that PA at baseline differed significantly between boys (48.3 MET/week) and girls (40.0 MET/week). The interaction of MC and 1 mile run/walk had a positive influence on level of PA. The general trend for a decrease in PA level across years was attenuated or amplified depending on initial level of MC. The estimated rate of decline in PA was negligible for children with higher levels of MC at 6 years, but was augmented by 2.58 and 2.47 units each year, respectively, for children with low and average levels of initial MC. In conclusion MC is an important predictor of PA in children 6–10 years of age.

Motor coordination, physical activity and fitness as predictors of longitudinal change in adiposity during childhood

Abstract The purpose of this study was to examine the influence of motor coordination (MC), physical fitness (PF) and physical activity (PA) on the development of subcutaneous adiposity in a sample of children followed longitudinally from 6 to 10 years of age. Participants were 142 girls and 143 boys. Height, weight, and the triceps and subscapular skinfolds were measured annually between the ages of 6 and 10 years. PA was estimated with the Godin–Shephard questionnaire. MC was evaluated with the Körperkoordination Test für Kinder (KTK) test battery, and PF was assessed with four Fitnessgram tests: curl-ups (CU), push-ups (PU), trunk-lifts (TL) and one mile run/walk (MRW). Hierarchical linear modelling with MC, PF items and PA as predictors of the sum of two skinfolds (SKF) was used. The results showed that boys and girls differed significantly in SKF at baseline (girls: 19.7 mm; boys: 16.6 mm). Three PF items (CU, PU and MRW) and MC had a positive influence on SKF. For each unit improvement in CU, PU, MRW and MC, SKF was reduced by 0.06, 0.04, 0.06 and 0.12 mm, respectively. In conclusion, motor coordination, muscular strength and endurance, and aerobic endurance attenuated the accumulation of subcutaneous adipose tissue during childhood.

Development and Construct Validation of an Inventory for Assessing the Home Environment for Motor Development

A contemporary view of early childhood motor development considers environmental influences as critical factors in optimal growth and behavior, with the home being the primary agent. However, there has been minimal research examining the relationship between motor development and the home. The present study addresses this gap with the goal of creating an innovative parental self-report instrument to assess the quality and quantity of factors (affordances and events) in the home that are conducive to enhancing motor development in children ages 18–42 months. Following initial face validity determination, expert opinion feedback and selective pilot testing, construct validity was examined using 321 Portuguese families. Factor analysis techniques were used to: (a) compare competing factorial models according to previous theoretical assumptions, and (b) analyze the fit of the preferred model. Of the five plausible models tested, the five-factor solution provided the best fit to the data. Reliability was established through the scale reliability coefficient with a value of .85. The findings of this study suggest that the Affordances in the Home Environment for Motor Development Self-Report is a valid and reliable instrument to assess how well home environments afford movement and potentially promote motor development.

Developmental pathways of change in fitness and motor competence are related to overweight and obesity status at the end of primary school

OBJECTIVES To test how different developmental pathways of health-related physical fitness and motor competence tests relate to weight status (overweight and obesity) at the end of primary school. DESIGN Longitudinal study on growth, health-related physical fitness, and motor competence of 472 primary school children assessed yearly throughout 1st to 4th grade, with an average age of 6.3±0.7 years of age at 1st grade. METHODS Childrens pathways of change on each of the fitness and motor competence tests were determined along the four years of the study. Participants were divided into three groups according to their rate of change in each test over time: Low Rate of Change, Average Rate of Change, and High Rate of Change. A logistic regression was used to predict the odds ratio of becoming overweight or obese, depending on the developmental pathway of change in fitness and motor competence across childhood. RESULTS Children with a low or average rate of change in their developmental pathways of fitness and motor competence were several times more prone to become overweight or obese at the end of primary school (OR 2.0 to 6.3), independent of sex and body mass index at baseline. Specifically, a negative developmental pathway (Low Rate of Change) in cardiorespiratory fitness demonstrated over a six-fold elevated risk of being overweight or obese, compared to peers with a positive pathway. CONCLUSIONS Not all children improve their motor competence and fitness levels over time and many actually regress over time. Developing positive fitness and motor competence pathways during childhood protects from obesity and overweight.

Influence of age, sex and somatic variables on the motor performance of pre-school children

Abstract Background: Biological factors can affect the motor development process of children. However, the magnitude of these effects throughout the developmental process remains fairly unknown. Aim: To determine the influence of age, sex and selected somatic measures on the motor performance of pre-school children. Subjects and methods: Three hundred and sixty-seven pre-schoolers (172 boys and 195 girls), aged from 3–5 years old, were recruited from 10 public pre-schools located in the district of Viana do Castelo, Portugal. The children’s motor performance was assessed by five motor sub-tests of Peabody Developmental Motor Scales-2: grasping, visuo-motor integration, stationary, locomotion and object manipulation sub-tests. Age, sex, height, weight and BMI were considered as hypothetical predictors of motor performance. Pearson’s correlation test and multiple linear regression analysis were used to explore the magnitude of the relationship between motor sub-tests and the hypothetical predictors. Results: Depending on the motor sub-test and age group, the models predicted motor performance from a minimum of 3.6% to a maximum of 34.4%. Age in months and sex stood out as the main predictors of motor performance. Conclusions: The relationship between motor performance and selected biological factors varied with age and with the specificity of the motor test.

Physical fitness predicts adiposity longitudinal changes over childhood and adolescence

OBJECTIVES The purpose of this study was to examine the influence of physical fitness (PF) on the development of subcutaneous adipose tissue in children followed longitudinally over a 9 year period ranging from childhood to adolescence. DESIGN This longitudinal study followed 518 healthy participants (262 boys, 256 girls) over a 9-year period ranging from childhood (age 6) to adolescence (age 15). Adiposity (triceps and subscapular skinfolds), and fitness (60s sit-ups, flexed arm hang, standing long jump, 50m dash, 10m shuttle run, sit-and-reach, and 20m pacer run) were assessed at four annual time points during primary school, and on a follow up, 6 years later, during secondary school. METHODS Growth in subcutaneous fat was modeled within a HLM statistical framework, using fitness components as time changing predictors. RESULTS Flexed arm hang (β=-0.059; p=0.000), standing long jump (β=-0.072; p=0.000), 60s sit-ups (β=-0.041; p=0.040), 50m dash (β=0.956; p=0.000), and 20m PACER (β=-0.077; p=0.000) tests, were found to predict changes on body fat growth over the years, independently of sex. CONCLUSIONS Improving PF individual levels can positively influence adiposity deposition over the time period covering childhood and adolescence. That occurs independently of the typical sex differentiated adiposity growth.

Development of adiposity, obesity and age at menarche: an 8-year follow-up study in Portuguese schoolgirls

Abstract Aim: It has been suggested that the decline in menarcheal age is associated with the increase of obesity prevalence. Objective: To examine the association between age at menarche and adiposity development from age 7 to 15 years. Subjects: A cohort of 109 schoolgirls from Viana do Castelo (Northern Portugal). Methods: Anthropometric measurements (height, weight, and triceps and subscapular skinfold thicknesses) were longitudinally obtained at 7, 8, 9, and 15 years. Waist circumference and self-reported age at menarche were obtained at age 15. Obesity was defined by the cut-off value of 30% body fat. Ages of <12 years, 12–13 years, and >13 years were classified as early menarche (EM), average menarche (AM) and late menarche (LM), respectively. Results: Median menarcheal age was 12.0 years (range, 8–15 years), with 26.6% of girls classified as EM. Compared with their LM peers, EM girls were always fatter (p=0.001) and had higher waist circumference at age 15 (p=0.009). All variables showed significant negative associations with age at menarche, except subscapular to triceps skinfold ratio at all ages and height at age 15. At both ages 9 and 15 years, LM girls had the lowest prevalence of obesity (4.5% and 9.1%, respectively). The 8-year incidence of obesity in EM girls was 24.1%, while that in the AM plus LM group was 13.8% (p=0.005). Conclusion: EM seems to be a risk factor for the development of obesity during adolescence. However, this vulnerability may start to be programmed before menarche as girls with precocious menarche were already fatter than their late-maturing peers at age 7 years.

Weight status is associated with cross-sectional trajectories of motor co-ordination across childhood

BACKGROUND Research indicates the development of motor co-ordination (MC) may be an important contributing factor to positive or negative weight trajectories across childhood. OBJECTIVES To analyse cross-sectional associations between MC and weight status in children (boys n = 3344 - girls n = 3281), aged 6-11 years and assess overweight/obese risk across different ages. METHODS Body mass index (BMI) was calculated [body mass (kg)/height (m(2))]. MC was evaluated using the Körperkoordination Test für Kinder (KTK) and a motor quotient (MQ) was calculated. MQ distribution data were split into tertiles. The effect of age, sex and MQ tertiles on BMI and MC was tested with a factorial anova. A logistic regression also was performed to calculate odd ratios (OR) for being overweight/obese at each age. RESULTS Children with higher MQ demonstrated lower BMI levels (F(2,6224) = 222.09; P < 0.001). Differences in BMI among MQ tertiles became larger across age (F(10,6224) = 4.53; P < 0.001). The OR of being overweight/obese in both sexes within the lowest MQ tertile increased in each age group from 6 to 11 years. Specifically, OR increased from 2.26 to 27.77 and from 1.87 to 6.81 in boys and girls respectively. CONCLUSIONS Children with low levels of MC have a higher risk of being overweight/obese and this risk increases with age.

Motor profile of Portuguese preschool children on the Peabody Developmental Motor Scales-2: A cross-cultural study

This study was designed to examine the cultural sensitivity of the PDMS-2 for Portuguese preschool children aged 36-71 months. A total of 540 children (255 males and 285 females) from 15 public preschools of Viana do Castelo, Portugal, were assessed. Age and gender effects in motor performance were examined. Results indicated that PDMS-2 is valid instrument to differentiate Portuguese age groups. Girls presented higher scores than boys in the Grasping and Visuo-motor integration subtests and lower scores in the Object Manipulation subtest. Portuguese preschoolers performed above US norms on Grasping, Visual-motor integration, and Stationary subtests, and bellow on Locomotion and Object Manipulation subtests. Overall, Portuguese children showed better results on the Fine Motor Quotient comparing to the Gross Motor Quotient. These results underline different motor development profiles between Portuguese and American children.

Validity and reliability of a pictorial instrument for assessing perceived motor competence in Portuguese children.

BACKGROUND It is important to assess young childrens perceived Fundamental Movement Skill (FMS) competence in order to examine the role of perceived FMS competence in motivation toward physical activity. Childrens perceptions of motor competence may vary according to the culture/country of origin; therefore, it is also important to measure perceptions in different cultural contexts. The purpose was to assess the face validity, internal consistency, test-retest reliability and construct validity of the 12 FMS items in the Pictorial Scale for Perceived Movement Skill Competence for Young Children (PMSC) in a Portuguese sample. METHODS Two hundred one Portuguese children (girls, n = 112), 5 to 10 years of age (7.6 ± 1.4), participated. All children completed the PMSC once. Ordinal alpha assessed internal consistency. A random subsamples (n = 47) were reassessed one week later to determine test-retest reliability with Bland-Altman method. Children were asked questions after the second administration to determine face validity. Construct validity was assessed on the whole sample with a Bayesian Structural Equation Modelling (BSEM) approach. The hypothesized theoretical model used the 12 items and two hypothesized factors: object control and locomotor skills. RESULTS The majority of children correctly identified the skills and could understand most of the pictures. Test-retest reliability analysis was good, with an agreement ration between 0.99 and 1.02. Ordinal alpha values ranged from acceptable (object control 0.73, locomotor 0.68) to good (all FMS 0.81). The hypothesized BSEM model had an adequate fit. CONCLUSIONS The PMSC can be used to investigate perceptions of childrens FMS competence. This instrument can also be satisfactorily used among Portuguese children.