Associations between 24 hour movement behaviours and global cognition in US children: a cross-sectional observational study

Abstract

Background: Childhood is a critical period for brain development, and the behaviours that comprise a typical 24-hour day contribute to cognitive performance in children. This study investigated the relationship between cognition and meeting the 24-hour movement behaviour guidelines of ≥60 minutes of physical activity, ≤2 hours of recreational screen time, and 9–11 hours of sleep per day in 9–10 year-olds. Methods: This study presents cross-sectional data from the first annual curated release of the Adolescent Brain Cognitive Development Study (ABCD) – a 10-year longitudinal, observational study investigating brain development in US children. Data were collected from 21 study sites across the United States between September 2016 and 2017. Participants were 4,524 US children aged 9–10 years. Exposures were combinations of adherence to physical activity, recreational screen time, and sleep duration recommendations and number of recommendations met. The primary outcome was global cognition and secondary outcomes were crystallized and fluid intelligence. Findings: The mean (SD) number of guideline recommendations met was 1·1 (0·9). Overall, 51·0% of participants met the sleep recommendation, 36·6% met screen time, and 17·5% met the physical activity recommendation. 70·6% of participants met at least 1, whereas 4·8% of participants met all 3 recommendations. Multi-level regression analysis revealed a statistically significant positive association between global cognition and each additional recommendation met [β=1·44 (95% CI: 0·82 – 2·07), p<0·001]. There was a statistically significant positive association between global cognition and meeting sleep + screen recommendations [β=5·15 (95% CI: 3·56 – 6·74), p<0·001] or meeting the screen-only recommendation [β=4·25 (95% CI: 2·50 – 6·01, p<0·001] compared to not meeting any recommendations. Interpretation: Meeting the recommendations of the 24-hour movement guidelines was associated with superior global cognition in this sample of US children. These findings highlight the importance of limiting recreational screen time and encouraging healthy sleep for promoting better cognition in children.

Delineating and validating higher-order dimensions of psychopathology in the Adolescent Brain Cognitive Development (ABCD) study

“…Demographic characteristics for participants in this data release have been reported elsewhere. 42 All procedures were approved at each site by institutional ethics boards. Parents or guardians provided written informed consent after the procedures had been fully explained and children assented before participation in the study.…”

Lifestyle Habits Predict Academic Performance in High School Students: The Adolescent Student Academic Performance Longitudinal Study (ASAP)

“…A possible mechanism that could explain the relationship between lack of sleep and academic performance is sleepiness during classes, which could affect academic performance negatively [15]. In addition, lack of sleep may decrease working memory [16] and cognitive functions [6] and in turn, this could lead to a poorer academic performance.…”

“…For example, a study conducted in 395 grade 7 Chileans reported that adolescents who spent more than 2 h per day in front of a screen seems to present a lower academic performance than adolescents who spent 2 h or less per day in front of a screen [17]. Possible mechanisms explaining these associations are the reduction of sleep duration [6] and cognitive control [6,20]. However, results of recent studies suggest that the influence of screen time on academic performance and on cognitive control vary depending on the type of screen used [6].…”

“…The benefits of adopting a healthy lifestyle go further than just improving a health condition. Indeed, during adolescence, less screen time as well as good eating and sleeping habits have been shown to be associated with better cognitive control and academic performance [5,6].…”

Seven days in medicine: 26 September to 2 October 2018

“…Limiting children’s time watching screens, including phones and television, to less than two hours a day may improve their cognition, a study published in Lancet Child and Adolescent Health showed 3. The study of 4520 US children aged 8-11 showed better cognition the more closely they followed guidelines recommending under two hours of recreational screen time a day, at least 60 minutes of physical activity, and 9-11 hours of sleep a night.…”