Motor skill competence and moderate- and vigorous-intensity physical activity: a linear and non-linear cross-sectional analysis of eight pooled trials.

BACKGROUND: Few studies have examined the relationship between motor skill competence and device-measured physical activity in large samples and none have used non-linear modelling. This study assessed the linear and non-linear associations between motor skill competence and physical activity in children using pooled data from eight studies. METHODS: Cross-sectional ActiGraph accelerometer and motor skills competence data from 988 children (50.8% boys) aged 3-11 years were included. Total, object control and locomotor skill competence were assessed using the Test of Gross Motor Skill Development. Linear mixed models were fitted to examine linear associations between motor skill competence and physical activity. Then, restricted cubic splines models were used to assess potential non-linear relationships. Interactions by sex and age were assessed. RESULTS: There was evidence of positive linear associations between total skill, and object control and locomotor skills, with moderate- and vigorous-intensity physical activity; however, the associations with total skill competence and object control better fitted a non-linear model. Non-linear models indicated associations were positive but relatively weak in the low to mid ranges of TGMD/object control scores but at high ranges (~ > 70 out of 100/ and ~ 35 out of 50) the association strength increased for both moderate- and vigorous-intensity physical activity. There were sex interactions for locomotor skills only, specifically for vigorous activity with boys having a stronger positive association than girls. CONCLUSIONS: There appears to be a threshold for object control skill proficiency that children need to reach to enhance their physical activity levels which provides support for a motor skill "proficiency barrier". This provides a tangible benchmark for children to achieve in motor competence programs.

Interventions to increase physical activity in children 0-5 years old: a systematic review, meta-analysis and realist synthesis.

OBJECTIVE: The objective of the study is to evaluate the effectiveness of interventions to increase physical activity (PA) in 0-5 year olds and to determine what works, for whom, in what circumstances. DESIGN: Systematic review, meta-analysis and realist synthesis. DATA SOURCES: Embase and EBSCOhost (Academic Search Complete, CINAHL Complete, Global Health, MEDLINE Complete, PsycINFO, SPORTDiscus with full text), up to and including April 2017. ELIGIBILITY CRITERIA: Published in a peer-reviewed English language journal; randomized or controlled trial design; aimed to increase children's PA levels; reported on objectively assessed PA in children between 0 and 5.9 years at baseline and post-intervention. RESULTS: Thirty-four studies were included in the review, mostly conducted in the preschool/childcare setting. Meta-analyses showed an overall non-significant (Z = 0.04, p = 0.97) mean difference of 0.03 (95% CI = -1.57, 1.63) minutes/day for light-intensity PA (n = 11). The overall mean difference for moderate-intensity to vigorous-intensity PA (n = 21) was 2.88 (95% CI = 1.54, 4.23) minutes/day, indicating a small but significant overall positive effect (Z = 4.20, p < 0.001). The realist synthesis provided insights into the key contexts and mechanisms that appeared to be effective at changing children's PA. CONCLUSION: Based on a quantitative and qualitative examination of the evidence, this review provides specific recommendations for effective early childhood PA interventions for practitioners and policymakers.

Physiological applications of consistency-based diagnosis.

This research attempts to span the gap between the AI in medicine (AIM) and consistency-based diagnosis (CBD) communities by applying CBD to physiology. The highly-regulated nature of physiological systems challenges standard CBD algorithms, which are not tailored for complex dynamic systems. Extensions of CBD to dynamic domains have relied upon complete quantitative dynamic simulation for behavior prediction. However, dynamic simulations, particularly by continuous systems, tend to inundate key CBD processes (such as truth maintenance and information-theoretic testing) with a deluge of temporal information. To combat this problem, we separate static from dynamic analysis so that CBD performs static diagnosis at a selected set of time slices. Knowledge of the qualitative behavior of physiological regulators is then used to link static intra-slice diagnoses into a complete dynamic account of the progression of a physiological condition. This provides a simpler approach to CBD of dynamic systems while adding a new capability to CBD: the detection of dynamic faults (i.e. those that do not necessarily persist throughout diagnosis). This paper describes (a) a few of the problems underlying CBD extensions to dynamic systems, (b) our hybrid static-dynamic, qualitative-quantitative approach, (c) our implemented IDUN system, (d) IDUN's diagnosis of volume-loading hypertension, (e) the generalization of IDUN's modeling perspective to the compartmental ontology, and (f) IDUN's use of compartmental models to diagnose acidosis.