The research forms part of the SUNRISE International Study of Movement Behaviours in the Early Years, a global effort to understand how young children around the world accumulate movement and rest. In the Canadian arm, published in the Journal of Activity, Sedentary and Sleep Behaviors, researchers analysed data from 654 preschoolers with an average age of about forty-seven months, roughly fifty-three percent of whom were boys. Families and childcare centres from across Canada participated, and the study received funding from the Canadian Institutes of Health Research.

What sets this study apart methodologically is its use of compositional data analysis, a statistical framework designed for data that are inherently constrained to sum to a constant. Traditional analyses often examine each behaviour in isolation, asking, for instance, whether more sleep predicts better memory while ignoring the fact that extra sleep must necessarily displace some other behaviour. Compositional approaches treat the full twenty-four-hour day as an interdependent system, expressing each behaviour’s share relative to the others through isometric log ratio transformations before testing associations with outcomes.

The measurement of behaviour was equally rigorous. Each child wore a waist-mounted ActiGraph wGT3X+ accelerometer for seven consecutive days, providing an objective record of how much time was spent asleep, sedentary, or moving at light and moderate-to-vigorous intensities. Cognitive abilities were assessed with validated Early Years Toolbox tasks delivered on iPads, which measure inhibition, the capacity to suppress impulses and automatic responses, and working memory, the mental workspace that holds and manipulates information over short periods. Both skills are considered foundational for school readiness and later academic achievement.

In unadjusted statistical models, the overall composition of movement behaviours was significantly associated with both inhibition and working memory, although the amount of variance explained was small, with R-squared values of 0.03 for inhibition and 0.02 for working memory. However, once the researchers accounted for covariates such as demographic characteristics, those associations were no longer statistically significant. This pattern suggests that while movement behaviours may relate to cognition, the magnitude of any effect in preschool years is likely small and partly entangled with other family and child factors.

The compositional substitution analyses offered a more granular view. These models estimate what would happen to a cognitive outcome if one behaviour were swapped for another while the rest of the day stayed constant. One notable finding emerged: replacing light physical activity with sedentary time was associated with better inhibition. In other words, in this dataset, shifting a young child from gentle movement into sedentary pursuits appeared linked to slightly stronger impulse control, a counterintuitive result the authors flag as a point for future investigation rather than a prescription.

Perhaps the most eye-catching results came from the so-called Goldilocks analysis, a technique that searches for the daily allocation of the four behaviours associated with the best cognitive outcomes. For inhibition, the optimal day included about 118 minutes of moderate-to-vigorous physical activity, 726 minutes of sleep, 258 minutes of light activity, and 337 minutes of sedentary time. For working memory, the optimum shifted to roughly 164 minutes of moderate-to-vigorous activity, 664 minutes of sleep, 323 minutes of light activity, and 288 minutes of sedentary time.

Those numbers carry a striking implication when set against current guidance. The sleep values associated with optimal cognition fell comfortably within existing twenty-four-hour movement guidelines for preschoolers, reinforcing sleep as the one behaviour where current recommendations and this study’s optimal profile align. But the optimal amounts of moderate-to-vigorous physical activity exceeded current recommendations by one to two hours, suggesting, on the surface, that preschoolers might benefit cognitively from roughly double the recommended dose of energetic play. The authors themselves urge caution, noting that more work is needed before such targets could be promoted with confidence.

Another strength of the study was its attention to demographic subgroups. Previous compositional studies have largely ignored whether associations differ between three- and four-year-olds, between boys and girls, or between children in urban and rural settings. When the Canadian team ran their models separately for these groups, no significant reallocation effects emerged in any subgroup, indicating that the overall pattern of weak, composition-level associations holds broadly rather than being driven by a particular slice of the preschool population.

The authors are careful about what these findings can and cannot support. Movement behaviours, they conclude, may play a role in preschool cognitive development, but the effect is likely small, and the adjusted models remind us that many other influences shape how a four-year-old’s mind matures. Still, the study provides a useful benchmark for researchers worldwide, offering concrete estimates of optimal daily activity and sleep patterns against which future work can be compared. For parents, the practical takeaway is reassuring rather than radical: protect good sleep, encourage plenty of active play, and keep sedentary time modest, while remembering that a child’s growing brain depends on far more than the clock-time ledger of a single day.

Subject of Research: Associations between 24-hour movement behaviours and cognitive development in preschoolers

Article Title: Compositional data analysis of the associations among 24-hour movement behaviours and cognitive development of preschoolers across Canada: a SUNRISE study

Article References: Buchanan, S., Boyd, M., Bremer, E., Bruijns, B. A., Caldwell, H. A. T., Carson, V., Faulkner, G., Harandian, K., Hawthorne, M., Kuzik, N., Martins, R., Pagani, L., Potter, M., Tucker, P., & Tremblay, M. S. (2026). Compositional data analysis of the associations among 24-hour movement behaviours and cognitive development of preschoolers across Canada: a SUNRISE study. Journal of Activity, Sedentary and Sleep Behaviors. https://doi.org/10.1186/s44167-026-00115-0

Image Credits: AI Generated

DOI: 10.1186/s44167-026-00115-0

Keywords: preschoolers, cognitive development, working memory, inhibition, physical activity, sedentary behaviour, sleep, compositional data analysis, accelerometers, SUNRISE study, movement behaviours, 24-hour guidelines

The 24-Hour Movement Guidelines for the Early Years represent an integrated approach to healthy development in early childhood, recognizing that sleep, physical activity, and sedentary behavior are not isolated habits but interlocking components of a single 24-hour cycle. For children aged 3 to 4 years, the guidelines recommend between 10 and 13 hours of good-quality sleep per day, at least 180 minutes of total physical activity spread across the day, of which at least 60 minutes should be moderate-to-vigorous intensity, no more than one hour of screen time, and no more than one hour of restrained sitting, such as being confined in a stroller, high chair, or car seat for extended periods. Meeting the recommendations individually is one matter; achieving all of them simultaneously on a consistent basis is substantially harder, and that is precisely where the new study focused its attention.

Measurement rigor distinguishes this surveillance effort from earlier surveys that relied largely on parental questionnaires. The research team, led by Sabrina Buchanan and Mark S. Tremblay of the Children’s Hospital of Eastern Ontario Research Institute, together with collaborators from institutions including Western University, Dalhousie University, the University of Alberta, the University of British Columbia, the University of Montreal, Acadia University, and the University of Wollongong, fitted each child with a waist-worn ActiGraph wGT3X+ accelerometer for seven consecutive days and nights. These devices captured objective data on movement intensity and sleep duration, while parents reported on their children’s screen time and time spent restrained in seats and strollers. The study formed part of the SUNRISE International Study of Movement Behaviours in the Early Years and was funded by the Canadian Institutes of Health Research.

Within the final analytic sample of 631 children, 29.0 percent met the overall movement guidelines when accelerometer-estimated measures were prioritized. That headline figure conceals a striking asymmetry in how children performed on each individual behavior. On the positive side, physical activity proved to be a genuine strength of this cohort: every child in the sample accumulated the recommended 180 minutes of total daily physical activity, and 92.4 percent achieved the more demanding threshold of at least 60 minutes of moderate-to-vigorous physical activity per day. Sleep was also largely on target, with between 74.6 percent and 92.0 percent of children meeting the sleep recommendation, depending on whether accelerometer estimates or parent reports were used.

The weak link in the 24-hour equation was sedentary behavior. Only 40.7 percent of children met the sedentary behavior recommendations overall, and the two components told divergent stories. Screen time was the more problematic of the pair, with just 57.1 percent of children staying within the one-hour daily limit, while 71.8 percent met the recommendation for restrained sedentary time. In an era when tablets, smartphones, and televisions are woven into daily family life, the finding that more than four in ten preschoolers exceed recommended screen limits will resonate with pediatricians and early childhood educators who have warned that early excessive screen exposure can displace active play, conversation, and sleep, all of which are critical to brain development during these years.

Beyond the headline prevalence figures, the study uncovered meaningful demographic patterns in who was meeting which guidelines. Girls were significantly less likely than boys to meet the moderate-to-vigorous physical activity recommendation, with an adjusted odds ratio of 0.37, meaning their odds were less than half those of boys. This gender gap, emerging as early as ages 3 and 4, suggests that differences in physical activity participation between males and females are established well before formal schooling begins, reinforcing calls from the study’s authors for targeted strategies to support young girls’ physical activity participation, including inclusive play environments and deliberate encouragement from parents and early childhood educators.

Geography also mattered, though in an unexpected direction. Children living in urban areas were more likely to meet sedentary behavior recommendations than their rural counterparts, with an adjusted odds ratio of 1.51. The authors note that systematic monitoring of preschool movement behaviors has often overlooked subgroups such as males versus females and urban versus rural residents, making these comparisons an important contribution. The rural disadvantage in sedentary time may reflect longer durations spent restrained in car seats during travel to childcare, services, and activities, though the study’s cross-sectional design cannot definitively establish the underlying causes.

Perhaps most intriguing were the age-related findings. Older children within the sample were less likely to meet the overall guidelines, with an adjusted odds ratio of 0.49 per unit increase in age, and less likely to meet sleep recommendations, with an odds ratio of 0.96. Yet the same older children were more likely to meet the moderate-to-vigorous physical activity recommendation, with an odds ratio of 1.08. This pattern suggests that as children approach kindergarten age, their waking hours become more active, but their sleep appears to erode, possibly reflecting later bedtimes, earlier morning routines, or the creeping influence of evening screen use. The net effect is that the delicate balance of the full 24-hour day tips away from the healthy profile as children grow older within the preschool window.

The authors are careful to frame these results within the limitations of a cross-sectional design, which captures a snapshot rather than trajectories over time, and within a sample drawn from childcare settings across five provinces. Methodological choices also mattered: the proportion meeting overall guidelines shifted depending on whether accelerometer-derived sleep estimates or parental reports were prioritized, a reminder that measurement modality can materially alter surveillance conclusions. Even so, the direction of the evidence is consistent with broader international literature showing that very young children are moving enough and sleeping reasonably well but sitting too much in front of screens.

The study’s conclusions point toward a clear public health priority. Because most children in the sample already met sleep and physical activity recommendations, the greatest gains lie in limiting sedentary time, particularly screen time, across the entire preschool population. At the same time, the authors emphasize that continued encouragement of healthy sleep and physical activity remains essential, and that specific, tailored strategies should be developed to support young girls’ physical activity participation. As part of the SUNRISE international surveillance network, this Canadian dataset also provides a benchmark against which future policy interventions, such as screen time guidance, active play programming in early childhood education and care settings, and provincial health promotion campaigns, can be evaluated. With early childhood representing a uniquely plastic developmental window, the difference between 29 percent and a far higher proportion of children meeting all four movement targets may ultimately be measured not in odds ratios but in lifelong health trajectories.

The SUNRISE initiative, of which this Canadian dataset forms a part, was designed to fill a conspicuous gap in global surveillance. While movement behavior monitoring has become routine for school-aged children and adolescents in many countries, comparable data for the early years have been sparse, and the SUNRISE network has sought to harmonize protocols so that preschool findings can eventually be compared across nations with very different childcare systems, climates, and cultural norms around sleep and screen use. The Canadian contribution, spanning five provinces and drawing participants through childcare centres, therefore serves both a national policy purpose and an international comparative one.

The integrated nature of the guidelines themselves reflects a relatively recent shift in thinking among exercise science and pediatric sleep researchers. Earlier guidance treated physical activity, sedentary behavior, and sleep as separate domains with separate targets, but time is inherently finite within a day, so gains in one behavior necessarily displace another. Modeling the full 24 hours as a single continuum allows researchers and practitioners to see trade-offs explicitly, and it explains why the proportion meeting all recommendations simultaneously is so much lower than the proportion meeting any single recommendation in this sample.

The accelerometer protocol also merits attention. Seven consecutive days of waist-worn monitoring captures both weekday and weekend behavior, which matters because preschoolers’ routines often differ markedly between childcare days and home days. Prioritizing device-based estimates over parental report reduces the social desirability bias that plagues questionnaire measures of screen time and sleep, though the divergence between accelerometer-estimated and parent-reported sleep prevalence in this study illustrates that even objective devices rest on assumptions about what constitutes sleep onset and wake.

Finally, the childcare setting through which families were recruited is itself a promising intervention lever. Early childhood education and care environments shape much of preschoolers’ daily movement, and provincial licensing standards governing active outdoor play and screen exposure could translate these surveillance findings into practical policy change.

Subject of Research: Compliance of 3- and 4-year-old Canadian children with 24-hour movement guidelines for sleep, physical activity, and sedentary behavior

Article Title: Proportion of 3- and 4-year-old children meeting individual and combinations of 24-hour movement guidelines across five Canadian provinces: a SUNRISE study

Article References: Buchanan, S., Bremer, E., Bruijns, B. A., Caldwell, H. A. T., Carson, V., Chong, K. H., Faulkner, G., Harandian, K., Hawthorne, M., Kuzik, N., Martins, R., Ong, M., Pagani, L., Potter, M., Tucker, P., & Tremblay, M. S. (2026). Proportion of 3- and 4-year-old children meeting individual and combinations of 24-hour movement guidelines across five Canadian provinces: a SUNRISE study. Journal of Activity, Sedentary and Sleep Behaviors. https://doi.org/10.1186/s44167-026-00113-2

Image Credits: AI Generated

DOI: 10.1186/s44167-026-00113-2

Keywords: 24-hour movement guidelines, preschool children, physical activity, sedentary behavior, screen time, sleep, SUNRISE study, accelerometry, public health surveillance, Canada, early childhood, health promotion