Adherence to 24-Hour Movement Recommendations and Health Indicators in Early Adolescence: Cross-Sectional and Longitudinal Associations in the Adolescent Brain Cognitive Development Study

Associations between meeting 24h movement behavior guidelines and cognition, gray matter volume, and academic performance in children and adolescents: a systematic review

BACKGROUND

24-h movement behaviors have a close relationship with children and adolescents' cognition, gray matter volume, and academic performance. This systematic review aims to precisely explore the associations between meeting different combinations of guidelines and the aforementioned indicators, in order to better serve public health policy.

METHODS

Computer retrieval was conducted on CNKI, Web of Science, PubMed, SPORT Discus and Cochrane library databases. The screening and data extraction processes were conducted by two researchers. This study used the Joanna Briggs Institute checklist for methodological quality assessment and the Grading of Recommendations Assessment, Development, and Evaluation system for the evaluation of the level of evidence. Descriptive statistical analysis is performed using frequency and percentage on the extracted data and key findings, primarily to assess the consistency of the positive benefits associated with meeting different guidelines and outcome variables.

RESULTS

A total of 10 studies were included (with 16 correlation analyses conducted), involving 51,566 children and adolescents aged between 4.2 and 15.9 years old. The included studies generally agreed upon the following associations: adherence to the screen time (ST) guidelines is positively linked to fluid intelligence; adherence to the sleep duration (SD) guidelines is positively linked to literacy; adherence to both ST and SD guidelines is associated with increased fluid intelligence and gray matter volume; and overall adherence to all guidelines is positively correlated with fluid intelligence. The included studies reported low certainty of evidence. Additionally, the included studies have provided clear evidence, but some studies did not strictly control confounding factors, and it is also unclear whether there is a larger effect size, hence the level of evidence is relatively low.

CONCLUSION

There are varying degrees of associations between different combinations of guidelines and cognition, gray matter volume, and academic performance, but further research is needed to confirm these findings, especially the relatively limited role of meeting physical activity guidelines.

Height development trends among 7-18-year-old school-age children in central plains of China between 2000 and 2019: A serial cross-sectional surveillance study in China

OBJECTIVE

The aim of this study was to analyze changes in height of 7-18-year-old school-age children in China during the year of 2000-2019.

METHODS

We used the survey data from the Chinese National Survey on Students' Constitution and Health in Henan Province for the years 2000, 2005, 2010, 2014, and 2019. Data were categorized into subgroups based on geographic location, gender, and age; mean, standard deviation, and Pearson's correlation coefficient were used to analyze trends in height change among children and adolescents and the correlation between socioeconomic indicators and height change.

RESULTS

The height of children and adolescents in Henan has shown a continuous upward trend. The height difference between urban and rural areas has gradually narrowed but has not disappeared. The correlation of height development trends between neighbouring urban areas was higher than in other areas. The level of medical care was significantly associated with the change in height for both boys (r = 0.950, p = 0.013) and girls (r = 0.897, p = 0.039); GDP per capita (r = 0.940，p = 0.018) was significantly associated with the change in height for boys only.

CONCLUSION

The height of Chinese children and adolescents will continue to maintain a positive growth trend, but we need to pay attention to the health status and nutritional intake of children and adolescents in economically disadvantaged areas in order to narrow the height disparity between different socio-economic groups.

Effects of Swimming Exercise on Early Adolescents' Physical Conditioning and Physical Health: A Systematic Review

BACKGROUND/OBJECTIVES

Swimming is a popular and cost-effective way to prevent sedentary behavior and improve physical conditioning and health during early adolescence. However, information on its impact and benefits on daily life activities is lacking. This systematic review aims to summarize the chronic effects of swimming on physical conditioning and physical health outcomes in early adolescents.

METHODS

The PRISMA 2020 guidelines were followed and PubMed, Scopus, Web of Science, and International Symposium of Biomechanics and Medicine in Swimming proceedings databases were searched. Eligibility criteria were defined on the PICOS framework (healthy adolescents in early puberty, swimming programmes or training, passive or active control groups, general effects on physical conditioning or health, longitudinal) and risk of bias was assessed using RoBANS 2.

RESULTS

From 2365 records, 20 non-randomized studies met the defined criteria. High heterogeneity in sample size and intervention was observed. While studies related to physical conditioning (n = 5) focused on physiological variables and muscular function, the evidence regarding physical health outcomes (n = 15) explored bone accrual, haemodynamics, body composition, musculoskeletal system, and lung growth. High overall risk of bias (70%) was observed due to strict criteria.

CONCLUSIONS

Swimming exercise seems to improve cardiorespiratory fitness, cardiac output, haemodynamics, heart growth, motor performance, and body composition of early adolescents. Despite clear evidence that exists on these chronic effects, research on bone health, postural deficit, motor skills, and sleep quality is still missing.

From "online brains" to "online lives": understanding the individualized impacts of Internet use across psychological, cognitive and social dimensions

In response to the mass adoption and extensive usage of Internet-enabled devices across the world, a major review published in this journal in 2019 examined the impact of Internet on human cognition, discussing the concepts and ideas behind the "online brain". Since then, the online world has become further entwined with the fabric of society, and the extent to which we use such technologies has continued to grow. Furthermore, the research evidence on the ways in which Internet usage affects the human mind has advanced considerably. In this paper, we sought to draw upon the latest data from large-scale epidemiological studies and systematic reviews, along with randomized controlled trials and qualitative research recently emerging on this topic, in order to now provide a multi-dimensional overview of the impacts of Internet usage across psychological, cognitive and societal outcomes. Within this, we detail the empirical evidence on how effects differ according to various factors such as age, gender, and usage types. We also draw from new research examining more experiential aspects of individuals' online lives, to understand how the specifics of their interactions with the Internet, and the impact on their lifestyle, determine the benefits or drawbacks of online time. Additionally, we explore how the nascent but intriguing areas of culturomics, artificial intelligence, virtual reality, and augmented reality are changing our understanding of how the Internet can interact with brain and behavior. Overall, the importance of taking an individualized and multi-dimensional approach to how the Internet affects mental health, cognition and social functioning is clear. Furthermore, we emphasize the need for guidelines, policies and initiatives around Internet usage to make full use of the evidence available from neuroscientific, behavioral and societal levels of research presented herein.

Association between meeting 24-h movement guidelines and health in children and adolescents aged 5-17 years: a systematic review and meta-analysis

Twenty-four-hour movement behaviors have significant implications for physical and mental health throughout one's lifespan. Consistent with movement behaviors, several countries have formulated and published 24-h movement guidelines. This review summarized the studies related to 24-h movement guidelines among children and adolescents from six databases (MEDLINE, EMBASE, PubMed, Web of Science, CINAHL, and SPORTDiscus). In a total of 61 studies that discussed compliance with 24-h movement guidelines, the overall adherence rate was very low (7.1%), with boys exceeding girls, children surpassing adolescents, and regional differences. A total of 39 studies examined the associations between 24-h movement guidelines and health indicators. Findings indicated that meeting all three guidelines was favorably associated with adiposity, cardiometabolic health, mental and social health, physical fitness, health-related quality of life, academic achievement, cognitive development, perceived health, dietary patterns, and myopia. Future research should utilize longitudinal and experimental designs to enhance our understanding of the associations between 24-h movement guidelines and health indicators, thereby aiding the formulation and refinement of such guidelines.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, CRD42023481230.

Is adherence to the 24-h movement guidelines associated with greater academic-related outcomes in children and adolescents? A systematic review and meta-analysis

The purpose of this systematic review was to synthesise the evidence for the association of adherence to the 24-h movement guidelines with academic-related outcomes in children and adolescents. This systematic review was based on the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement. PubMed, PsycINFO, Scopus, WOS, SPORTDiscus, and EMBASE were searched from their inception to 12 December 2023. The Joanna Briggs Institute (JBI) Critical Appraisal Checklist was used to assess the risk of bias of included studies. In total, 4326 records were identified through database searches; 10 articles met the inclusion criteria and were included in this systematic review. There were eight cross-sectional studies and two longitudinal studies; the main academic-related outcomes were academic achievement and cognitive function. A small association between adherence to all three recommendations and academic achievement (k = 5, r = 0.17, 95% CI = 0.10-0.24, I2 = 49%) was found compared to those who did not adhere to any recommendations.   Conclusion: Findings from this systematic review and meta-analysis reveal a small association between adherence to all three recommendations and greater academic achievement in children and adolescents. Nevertheless, it is imperative to underscore the need for more studies to establish robust evidence underpinning this relationship.   Trial registration: PROSPERO (CRD42021295403). What is Known: • Regular physical activity, reduced screen time, and optimal sleep duration are independently associated with improved academic-related outcomes in children and adolescents. • The associations between adherence to the 24-h movement guidelines and academic-related outcomes in children and adolescents have not been quantitatively synthesised. What is New: • There is a small but positive association between adherence to all three recommendations of the 24-h movement guidelines and greater academic achievement in children and adolescents. • Further well-designed research is needed to focus on academic achievement, cognitive function and classroom behaviours in young individuals.

Longitudinal associations of screen time, physical activity, and sleep duration with body mass index in U.S. youth

BACKGROUND

Youth use different forms of screen time (e.g., streaming, gaming) that may be related to body mass index (BMI). Screen time is non-independent from other behaviors, including physical activity and sleep duration. Statistical approaches such as isotemporal substitution or compositional data analysis (CoDA) can model associations between these non-independent behaviors and health outcomes. Few studies have examined different types of screen time, physical activity, and sleep duration simultaneously in relation to BMI.

METHODS

Data were baseline (2017-2018) and one-year follow-up (2018-2019) from the Adolescent Brain Cognitive Development Study, a multi-site study of a nationally representative sample of U.S. youth (N = 10,544, mean [SE] baseline age = 9.9 [0.03] years, 48.9% female, 45.4% non-White). Participants reported daily minutes of screen time (streaming, gaming, socializing), physical activity, and sleep. Sex-stratified models estimated the association between baseline behaviors and follow-up BMI z-score, controlling for demographic characteristics, internalizing symptoms, and BMI z-score at baseline.

RESULTS

In females, isotemporal substitution models estimated that replacing 30 min of socializing (β [95% CI] = -0.03 [-0.05, -0.002]), streaming (-0.03 [-0.05, -0.01]), or gaming (-0.03 [-0.06, -0.01]) with 30 min of physical activity was associated with a lower follow-up BMI z-score. In males, replacing 30 min of socializing (-0.03 [-0.05, -0.01]), streaming (-0.02 [-0.03, -0.01]), or gaming (-0.02 [-0.03, -0.01]) with 30 min of sleep was associated with a lower follow-up BMI z-score. In males, replacing 30 min of socializing with 30 min of gaming was associated with a lower follow-up BMI z-score (-0.01 [-0.03, -0.0001]). CoDA estimated that in males, a greater proportion of time spent in baseline socializing, relative to the remaining behaviors, was associated with a higher follow-up BMI z-score (0.05 [0.02, 0.08]). In females, no associations between screen time and BMI were observed using CoDA.

CONCLUSIONS

One-year longitudinal associations between screen time and BMI may depend on form of screen time, what behavior it replaces (physical activity or sleep), and participant sex. The alternative statistical approaches yielded somewhat different results. Experimental manipulation of screen time and investigation of biopsychosocial mechanisms underlying the observed sex differences will allow for causal inference and can inform interventions.

Examining the Bidirectional Associations Between Sleep Duration, Screen Time, and Internalizing Symptoms in the ABCD Study

PURPOSE

The likelihood of meeting sleep duration and screen time guidelines decreases as children develop toward adolescence. Simultaneously, the prevalence of internalizing symptoms increases. The purpose of this paper was to examine the bidirectional associations between sleep duration and screen time with internalizing symptoms in a one-year longitudinal study starting in late childhood.

METHODS

Participants were 10,828 youth (47.8% female) enrolled in the Adolescent Brain Cognitive Development Study. At baseline (mean age 9.9 years) and one-year follow-up (mean age 10.9 years), youth self-reported screen time for weekdays and weekend days. Responses were separately dichotomized as >2 versus ≤2 hours/day (meeting behavioral guidelines). Caregiver-reported youth sleep duration was dichotomized as <9 versus 9-11 hours/night (meeting behavioral guidelines). Caregivers reported internalizing symptoms via the child behavior checklist. The withdrawn/depressed, anxious/depressed, and somatic symptom child behavior checklist subscale t-scores were separately dichotomized as ≥65 (borderline clinical levels of symptoms and above) versus <65. Analyses were gender-stratified.

RESULTS

In females, longer baseline sleep duration was protective against withdrawn/depressed symptoms (odds ratio [OR] 0.6, 95% confidence interval [CI] 0.4-0.8) and somatic complaints (OR 0.8, 95% CI 0.6-0.97) one year later. In females, greater baseline weekend screen time was associated with increased risk of withdrawn/depressed symptoms (OR 1.6, 95% CI 1.1-2.2) one year later. No other significant associations were observed.

DISCUSSION

Longitudinal associations between sleep duration, weekend screen time, and internalizing symptoms were unidirectional (behavior preceding internalizing symptoms), among females only, and specific to withdrawn/depressed and somatic symptoms. These prospective study findings warrant attention and inform future research in this cohort.

Hippocampal Resting State Functional Connectivity Associated with Physical Activity in Periadolescent Children

Periadolescence is a neurodevelopmental period characterized by structural and functional brain changes that are associated with cognitive maturation. The development of the functional connectivity of the hippocampus contributes to cognitive maturation, especially memory processes. Notably, hippocampal development is influenced by lifestyle factors, including physical activity. Physical activity has been associated with individual variability in hippocampal functional connectivity. However, this relationship has not been characterized in a developmental cohort. In this study, we aimed to fill this gap by investigating the relationship between physical activity and the functional connectivity of the hippocampus in a cohort of periadolescents aged 8-13 years (N = 117). The participants completed a physical activity questionnaire, reporting the number of days per week they performed 60 min of physical activity; then, they completed a resting-state functional MRI scan. We observed that greater physical activity was significantly associated with differences in hippocampal functional connectivity in frontal and temporal regions. Greater physical activity was associated with decreased connectivity between the hippocampus and the right superior frontal gyrus and increased connectivity between the hippocampus and the left superior temporal sulcus. Capturing changes in hippocampal functional connectivity during key developmental periods may elucidate how lifestyle factors including physical activity influence brain network connectivity trajectories, cognitive development, and future disease risk.

Are 24-hour movement recommendations associated with obesity-related indicators in the young population? A meta-analysis

OBJECTIVE

This study aimed to determine the relationship between meeting all three 24-hour movement recommendations (i.e., physical activity, sleep duration, and screen time) and obesity-related indicators among young people.

METHODS

Four databases were systematically searched (PubMed, Scopus, Web of Science, and Cochrane Library).

RESULTS

Meeting the 24-hour movement recommendations was cross-sectionally associated with lower overall obesity-related indicators (r = -0.09, 95% CI: -0.11 to -0.06), but no longitudinal association was found. Regarding each obesity-related indicator separately, meeting all three recommendations was related to lower odds of overweight/obesity (odds ratio = 0.65, 95% CI: 0.56 to 0.76) and obesity alone (odds ratio = 0.28, 95% CI: 0.16 to 0.50). An inverse relationship between meeting 24-hour movement recommendations and BMI, BMI z score, waist circumference, and body fat was also found. Regarding subgroup analysis, the association between 24-hour movement recommendations and overall obesity-related indicators was similar regardless of sex, comparison used (meeting all three vs. not meeting [i.e., those who met zero to two of the movement behaviors] or meeting all three vs. none), and type of measure to assess 24-hour movement recommendations (i.e., self-reported or accelerometer-based measures).

CONCLUSIONS

Meeting all 24-hour movement recommendations may be a crucial factor in maintaining a healthy weight status in the young population.

Prospective associations between adherence to 24-hour movement guidelines and mental well-being in Chinese adolescents

Most evidence regarding the relationships between adherence to 24-hour movement guidelines and adolescent mental health have been derived from cross-sectional studies or have ignored positive mental health indicators. The current prospective study examined the associations between adherence to 24-hour movement guidelines and changes in mental well-being among Chinese adolescents over three months. 816 Chinese adolescents (Mage = 14.76 years; SD = 0.81) completed baseline and follow-up scales of 24-hour movement behaviours, mental well-being, and covariates. Linear mixed-effects models were used for data analyses, with adjustments for covariates and mental well-being at baseline. There was a significant improvement in mental well-being across the three months, and the improvement in mental well-being was positively associated with meeting any single guidelines and both physical activity and sleep guidelines but not adherence to all three guidelines. Meeting both physical activity and sleep recommendations appears to exert more significant benefits on mental well-being than meeting one or two other recommendations. An integrative approach to mental health promotion by focusing on 24-hour movement behaviours (at least physical activity and sleep) may be more effective than focusing on a single behaviour alone.

The Longitudinal Interplay between Sleep, Anthropometric Indices, Eating Behaviors, and Nutritional Aspects: A Systematic Review and Meta-Analysis

Sleep is fundamental for adolescents' healthy development but undergoes dramatic changes in quantity and quality due to the conflict between biological and social rhythms. Insufficient sleep has been associated with worse physical health status and irregular eating behaviors in adolescents. This review aims to systematically synthesize the longitudinal associations between adolescents' sleep dimensions (i.e., duration, timing, quality, and insomnia symptoms) and physical health indicators (i.e., anthropometric indices, fat percentage, and risk of obesity), eating behaviors, and nutritional aspects (i.e., type of diet related to the intake of specific foods and nutrients, amount and timing of food consumption, energy expenditure). A total of 28 longitudinal studies were included. The meta-analytic results showed that longer sleep duration, better sleep quality, and lower insomnia symptoms were associated with lower BMI and fat percentage and that shorter sleep duration (<7 h) and lower sleep quality were associated with a higher risk of obesity. Conversely, anthropometric indices were not related to sleep over time. Limited literature examined the bidirectional association between adolescents' sleep and their eating behaviors and nutritional aspects. Such knowledge sheds new light on the role of sleep for adolescents' health, highlighting the need to examine further the interplay between these variables.

Toward an Integrated Consideration of 24 h Movement Guidelines and Nutritional Recommendations

While physical activity, sleep and sedentary behaviors are almost always considered independently, they should be considered as integrated human behaviors. The 24 h Movement approach proposes a concomitant consideration of these behaviors to promote overall health. Not only do these behaviors impact energy expenditure, but they have also been shown to separately impact energy intake, which should be further explored when considering the entire integration of these movement behaviors under the 24 h movement approach. After an evaluation of the prevalence of meeting the 24 h Movement and dietary recommendations, this review summarizes the available evidence (using English publications indexed in PubMed/MEDLINE) regarding the association between the 24 h Movement Guidelines and eating habits. Altogether, the results clearly show the beneficial impact of promoting the 24 h guidelines simultaneously, highlighting that the higher the number of respected movement recommendations, the better eating behaviors in both children and adults. Importantly, our results point out the importance of emphasizing the need to reach sedentary guidelines for better eating habits. Movement and dietary behaviors appear closely related, and giving recommendations on one might impact the other. Combining the 24 h Movement with dietary Guidelines might be more efficient than promoting them separately in public health strategies.