Reliability levels of motor competence in youth athletes.

This study aimed to analyze the reliability of the tests included in the motor competence assessment (MCA) battery and compare the effects of the number of trials per test. Thirty female volleyball players (14.6 ± 1.3 years of age) were tested. The participants performed two or three trials of each test. Intra-class correlation (ICC) was calculated, and a paired sample t-test analyzed the variations between trials (1st vs. 2nd vs. 3rd). Results revealed a significant difference between the first and the second trials for jumping sideways [t(29) = -4.108, p < 0.01], standing long jump [t(29) = -3.643, p < 0.01], and shuttle run [t(29) = -3.139, p < 0.01]. No significant result was registered in the shifting platforms, ball throwing and kicking between the first and second trials. Hence, any difference was recorded between the second and third trial. High ICC values were registered in lateral jumps, among the three repetitions of ball kicking and ball throwing, and between the last two repetitions of shuttle run. Almost perfect values were recorded for the shifting platforms and standing long jump. Nevertheless, there seems to be a learning effect between the first and the second repetition-no differences were registered only considering the two manipulative tests. In conclusion, except for jumping sideways, the MCA tests are reliable and only need to be performed two times instead of three.

Relationship Among Changes in Sedentary Time, Physical Activity, and Body Mass Index in Young Schoolchildren: A 3-Year Longitudinal Study.

PURPOSES: To examine the association between sedentary time (ST) and light physical activity (LPA), moderate- to vigorous-intensity physical activity (MVPA), and body mass index (BMI), and to track these behaviors over a 3-year follow-up in young schoolchildren. METHODS: The final sample was 64 children (female: n = 36 or 56.3%), enrolled in schools in Porto, Portugal. Height and mass of children were measured by standard methods, and BMI was then calculated. ST, LPA, and MVPA were measured by accelerometer. Changes (Δ) and relative changes (Δ%) between 2009/2010 and 2012/2013 of ST, LPA, MVPA, and BMI were computed. Multiple linear regression analyses were fit to predict Δ%ST (outcome variable), by Δ%LPA, Δ%MVPA, and Δ%BMI (exposure variables). RESULTS: ST increased and LPA decreased significantly for whole sample (both Ps < .05). No statistically significant difference was found for MVPA over time. There were no differences for ΔST, ΔLPA, ΔMVPA, and ΔBMI between boys and girls. The Δ%LPA and Δ%MVPA were negatively associated with Δ%ST, whereas Δ%BMI was positively associated. Tracking coefficients varied from moderate to strong. CONCLUSIONS: Time spent in ST increases due to displacement of time in LPA. This reinforces public health measures and suggests the need for interventions focusing on offsetting the decline ST and increasing MVPA during childhood.

Exercise intervention and cardiovascular risk factors in obese children. Comparison between obese youngsters taking part in a physical activity school-based programme with and without individualised diet counselling: the ACORDA project.

AIM: To determine the effects of a school-based exercise intervention programme on cardiovascular risk factors, including body fat (BF), metabolic profile and physical activity (PA) in children with and without individualised dietary counselling approach (IDC and WIDC). SUBJECTS AND METHODS: Forty-six overweight children from 6-16 years old (25 girls, 54.3%; age = 10.3 ± 2.8) of six schools took part in an 8-month interdisciplinary, school-based intervention programme. All children were engaged in PA classes, but only one group was exposed to individualised counselling. Blood pressure (BP), lipids and lipoproteins, accelerometer-based PA, percentage of body fat (%BF) and trunk fat (%TF) measures were taken before and after intervention. General Linear Model (Repeated Measures ANOVA) adjusted for age, maturation and height change was used to analyse the longitudinal effect of individualised counselling between two evaluations in each group. RESULTS: Favourable changes were observed for %BF, %TF, systolic BP and total cholesterol in the IDC group. Subjects WIDC only increased light and moderate-vigorous PA. In IDC, significant effects for time * group interactions were found for systolic BP, total cholesterol and LDL-cholesterol, indicating that counselling might add favourable changes in these markers, beyond those explained by PA and growth. CONCLUSION: School-based interventions can contribute to counteracting obesity in youth, particularly when individualised dietary counselling is provided. Therefore, the link between schools and professional counselling should be strengthened to ensure consolidated changes towards healthy behaviours.

Associations Between Motor Competence, Moderate-to-Vigorous Physical Activity, and Body Mass Index Among Preschoolers Over 1 Year.

BACKGROUND: To examine the associations between motor competence (MC), moderate to vigorous physical activity (MVPA), and body mass index (BMI) changes over 1 year in preschoolers. METHODS: Fifty-four preschoolers (24 girls; 42.4%) aged 4-5 years old from the metropolitan area of Porto, Portugal comprised the sample. Height, body mass, and BMI were calculated. MC was assessed according to the Movement Assessment Battery for Children-2. MVPA was measured by accelerometry. For each participant, changes in MVPA, MC, and BMI over a year were computed. Different levels of MC were calculated; and then data were analyzed. RESULTS: The MVPA increased over time in all levels of MC in the follow-up. The BMI decreased over time for all levels in follow-up (P = .001). The preschoolers classified as at a high level of MC were more likely to spend more time in MVPA (in minutes) than their counterparts with low MC in follow-up. Multiple linear regression analyses, adjusted by sex and age, were fit to predict Δ% MC by Δ% MVPA and Δ% BMI. The Δ% MC was positively associated with Δ% MVPA. CONCLUSION: Increases in MC were positively associated with MVPA. Higher performance in MC increases due to time spent in MVPA. Improvement of MC in young children has potentially relevant policy implications related to MVPA and public health.