Physical activity, diet and other behavioural interventions for improving cognition and school achievement in children and adolescents with obesity or overweight

The effectiveness of exercise intervention for academic achievement, cognitive function, and physical health among children in Mongolia: a cluster RCT study protocol

Background

Many studies have demonstrated positive effects of physical activity on children’s health such as improved cardiorespiratory function and decreased obesity. Physical activity has also been found to have positive effects on academic achievement and cognitive function. However, there are few high quality RCT studies on this topic at present and the findings remain controversial.

Methods

This protocol describes cluster randomized controlled trials assessing the impact of school-based exercise intervention among children in Mongolia. The intervention consists of 3-min sessions of high intensity interval training combined with music implemented two times a week at school during study periods. The participants are children in the fourth grade in public elementary schools in the Sukhbaatar district in Ulaanbaatar, Mongolia. The participants are cluster randomized by school and allocated either to the intervention or control group. The primary outcome is academic achievement. Secondary outcomes are obesity/overweight, physical fitness function, lifestyle, mental health, and cognitive function.

Discussion

This cluster-RCT is designed and implemented to assess the effectiveness of exercise intervention on academic achievement, cognitive function, and physical and mental health among school-age children in Mongolia. This study will provide evidence to promote physical activities among children in low- and middle- income countries.

Trial registration

UMIN: UMIN000031062. Registered on 1st February 2018.

Do changes in weight status affect cognitive function in children and adolescents with obesity? A secondary analysis of a clinical trial

OBJECTIVES

It is unclear whether an association exists between obesity in children/adolescents and cognitive function, and whether the latter can be altered by body mass index (BMI) standard deviation score (SDS) reductions. We aimed to determine whether an association exists between BMI SDS and cognitive function in children/adolescents with obesity engaged in an obesity intervention. Second, we sought to determine if BMI SDS reduction at 12 months was associated with improved cognitive function.

DESIGN

Secondary analysis of a clinical trial.

PARTICIPANTS

Participants (n=69) were recruited from an obesity intervention. Eligible participants (recruited June 2013 to June 2015) were aged 6-16 years, with a BMI ≥98th centile or BMI >91st centile with weight-related comorbidities.

OUTCOME MEASURES

Primary outcome measure was change in BMI SDS from baseline at 12 months. Dependent variables of cognitive functioning and school achievement were assessed at baseline and 12 months, using dependent variables of cognitive functioning (elements of Ravens Standard Progressive Matrices, Wide Range Achievement Test-fourth edition and Wechsler Intelligence Scale for Children-fourth edition).

RESULTS

At baseline, BMI SDS was not associated with all aspects of cognitive function tested (n=69). Reductions in BMI SDS over time did not alter cognitive function overall. However, there was a greater reduction in comprehension standard scores in participants who increased their BMI SDS (adjusted estimated difference -6.1, 95% CI -11.6 to -0.6; p=0.03).

CONCLUSIONS

There were no observed associations between BMI SDS and cognitive function in participants, apart from comprehension in the exploratory analyses, which may have been a random finding. Further studies need to include larger longitudinal cohorts incorporating a wider BMI range at entry to determine whether our findings persist.

TRIAL REGISTRATION NUMBER

ANZCTR12611000862943; Pre-results.

Child temperament predicts the adiposity rebound. A 9-year prospective sibling control study

METHODS

We repeatedly examined 25889 siblings within the Norwegian Mother and Child Cohort Study, following them from the mothers' pregnancy through child age 8 years. Information on the children's height and weight was collected by means of health registries and maternal reports. Information on the siblings' temperament was collected by questionnaires completed when they were 1.5, 3, and 5 years old. We examined the associations of temperament at different child ages with the timing of the adiposity rebound among siblings and controls by means of growth curve and multilevel analyses.

RESULTS

Within siblings, high scores on the approach trait of sociability predicted an earlier adiposity rebound and high scores on the avoidance trait of shyness predicted a later adiposity rebound with timing differences ranging between 6 and 16 weeks. Surprisingly, negative emotionality did not predict the adiposity rebound. The associations between temperament and the adiposity rebound increased with increasing child age. The results within controls-comparing siblings with the population, broadly paralleled those within siblings.

CONCLUSIONS

The findings encourage the notion that child temperament functions as an early marker for the adiposity rebound. Future studies may advance our knowledge by including measures of child personality along the taxonomy of the adult Five Personality Factors.