Activity type matters for children’s cognitive development

Physical activity, outdoor play, and reading books boost children’s cognitive development, but excess physical activity may harm academic performance if it cuts into sleep time, as shown in a study from Singapore.

In an analysis of 24-hour movement behaviour data from The Growing Up in Singapore Toward healthy Outcomes (GUSTO) cohort, children who participated in organized physical activity (PA)/sports at ages 5.5 and 8 years had a higher mean executive function at age 8.5 years (z-score, 0.192 and 0.221, respectively). Moreover, those who participated in organized PA/sports at age 8 years had higher mean academic achievement at age 9 years (z-score, 0.239). [Front Public Health 2024:12:1412634]

Active play, whether indoor or outdoor, at 5.5 years had no significant effect on cognitive outcomes, but by 8 years, children who engaged in medium or high levels of outdoor active play exhibited better executive function (z-score, 0.201 and 0.211, respectively) and academic achievement (z-score, 0.273 and 0.204, respectively).

Notably, longer time spent doing moderate-to-vigorous physical activity (MVPA) at age 5.5 years was linked to a lower mean academic achievement at age 9 years (mean difference in z-score, −0.367, 95 percent confidence interval, −0.726 to −0.009). Despite this negative association, a significant improvement in academic achievement was observed when 5–60 minutes of MVPA per day were reallocated to sleep at age 5.5 years.

“For instance, reallocating 30 min from MVPA to sleep at age 5.5 resulted in a 0.214 increase in academic achievement z-score. The expected decrease in academic achievement z-score was relatively lower (−0.145) when the same amount of time was reallocated from sleep to MVPA at age 5.5 years. Similar changes were observed when reallocating MVPA and sleep time at age 8 years but they were not significantly associated with academic achievement,” according to the investigators.

Impact of specific activities

Certain domains of physical activity and sedentary behaviour, particularly organized PA/sports, outdoor play, and reading books were favourably associated with the outcomes of interest, whereas indoor play and screen-viewing showed an unfavourable association.

“Throughout each day, PA and SB are accumulated in different contexts and by engaging in diverse domains of activities. These activities contribute toward total PA and total SB, but specific activities or activities conducted in specific contexts may exhibit variable effects on cognitive and learning outcomes of children,” the investigators noted.

They explained that organized PA/sports may provide an environment that trains cognitive abilities such as inhibition and working memory, while simultaneously requiring children to function within a group setting. Meanwhile, exposure to natural environments during outdoor play has been shown to be beneficial for attention, memory, problem-solving skills, sensory stimulation, spatial awareness, and social interaction, among others, the investigators said. [Int J Environ Res Public Health 2018;15:800; Int J Environ Res Public Health 2021;18:745; Trends Neurosci Educ 2022;28:100182; Early Childhood Educ J 2021;49:463–71]

Future research directions

“Taken together, our study contributes significantly to the current literature and provides insights into potential opportunities for future research and the development of strategies to improve executive function and academic achievement in children,” the investigators said.

The findings support the current 24-hour movement behaviour guidelines in school-aged children, which encourage regular MVPA, limit screen viewing time, and promote adequate sleep for optimal health and development, they added. [https://www.who.int/publications/i/item/9789240015128; Appl Physiol Nutr Metab 2016;41:S311–S327]

“Future prospective studies using comprehensive and high-quality measures are warranted to investigate these complex relationships and interdependency of movement behaviours… [as well as] the trade-offs between time spent in different activities,” according to the investigators. They believed that such data could provide valuable insights to aid in the development of appropriate health promotion strategies.

The analysis included 432 children (53 percent male, 58 percent Chinese, mean BMI at age 5 years 15.49 kg/m²) from the GUSTO cohort. They wore an accelerometer around their wrist to measure 24-hour movement behaviour at ages 5.5 and 8 years. Executive function and academic achievement were assessed using NEuroPSYchology (NEPSY) and Wechsler Individual Achievement Tests at ages 8.5 and 9-years, respectively.