Is adherence to 24-Hour Movement Guidelines associated with a higher academic achievement among adolescent males and females?

Mapping the research using 24-h movement guidelines in children and adolescents: A bibliometric analysis

BACKGROUND

There are limited comprehensive bibliometric analyses that have examined research articles using the 24-h movement guidelines, which are necessary to evaluate the impact of the research field, map the scientific structure of the research landscape, and identify knowledge gaps.

OBJECTIVES

The aim of this study was to analyse the published research articles using the 24-h movement guidelines and assess their bibliometric characteristics.

METHODS

The search was conducted across all databases indexed in the Web of Science on March 6, 2024, and the bibliometric characteristics of studies published from 2016 onwards were analysed. Descriptive statistics and visualisations by the VOSviewer were used for the presentation of bibliometric characteristics.

RESULTS

120 studies using the 24-h movement guidelines in children and adolescents were included for analysis in this study. In general, number of the related publications using the 24-h movement guidelines increased from 2016 until now. 16 distinct clusters of author networking were displayed, of which the Canadian team was the strongest cluster with the highest research impacts. Of the included studies, cross-sectional studies accounted for the majority. North America and Europe were the leading two study locations across the included studies. Highly varied adherence rate to the 24-h movement guidelines across the included studies were observed. In terms of correlates and health outcomes of meeting the 24-h movement guidelines, separately, sociodemographic and health functioning characteristics were the most examined aspects.

CONCLUSIONS

This study provides a comprehensive scientific overview for research using the 24-h movement guidelines in children and adolescents, which may help guide potential research directions to improve the low compliance rates in this population.

Unveiling the association between 24-hour movement guidelines and academic engagement in adolescents

BACKGROUND

The aim of this research is to examine the relationship between adherence to different possible combinations of the 24-hour movement guidelines and academic engagement in adolescents.

METHODS

The cross-sectional study involved 742 students (median = 15.00; interquartile range = 3.00), aged 12 to 17 years (422 girls; 56.9%). Physical activity, screen time, sleep duration, and academic engagement were measured using self-report measurements. A generalized additive mixed model and a generalized linear mixed model were used to examine the association between adherence to 24-hour movement guidelines and academic engagement. Age, sex, socioeconomic status, body mass index, and school were considered as covariates.

RESULTS

Students who met all three guidelines showed the highest levels of academic engagement. Conversely, the lowest levels of academic engagement were observed in those who did not meet any of the guidelines. In addition, students' academic engagement was higher as more 24-hour movement guidelines were met.

CONCLUSION

Our results suggest the importance of jointly promoting 24-hour movement guidelines, as it appears to have greater benefits on adolescent academic outcomes.

IMPACT

Not meeting any of the three 24-hour movement guidelines was associated with lower academic engagement. Meeting all three 24-hour movement guidelines was related to higher academic engagement. Previous research has focused on the association between the three 24-hour movement guidelines and academic performance. However, the relationships of these behaviors on academic engagement have been little studied. The results of this study highlight the importance of promoting these three behaviors in adolescent academic outcomes.

The prospective associations of 24-hour movement behaviors and domain-specific activities with executive function and academic achievement among school-aged children in Singapore

Background

Physical activity (PA), sedentary behavior (SB), and sleep are collectively referred to as 24-h movement behaviors, which may be linked to cognitive development in children. However, most of the evidence was based on cross-sectional studies and/or solely relied on parent-reported information on children's behaviors, and it remains uncertain whether all domains/contexts of PA and SB are similarly associated with executive function and academic achievement.

Objective

We investigated the prospective associations of accelerometer-measured 24 h-movement behaviors and domain-specific PA and SB with executive function and academic achievement among school-aged children in Singapore.

Methods

The Growing Up in Singapore Toward healthy Outcomes (GUSTO) cohort used a wrist-worn accelerometer (Actigraph-GT3x+) to measure 24 h-movement behaviors data 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. Compositional data analyses were conducted to explore the associations of 24 h-movement behavior with outcomes, and multiple linear regression models to examine the associations of domain-specific PA and SB with outcomes (n = 432).

Results

Among 432 children whose parents agreed to cognitive assessments (47% girls and 58% Chinese), the composition of 24 h-movement behaviors at ages 5.5 and 8 years was not associated with executive function and academic achievement. However, higher moderate-to-vigorous PA (MVPA) relative to remaining movement behaviors at age 5.5 years was associated with lower academic achievement [Mean difference (95% confidence interval): -0.367 (-0.726, -0.009) z-score], and reallocating MVPA time to sleep showed higher academic achievement scores [30 min from MVPA to sleep: 0.214 (0.023, 0.404) z-score]. Certain domains of PA and SB, notably organized PA/sports, outdoor play, and reading books were favorably associated with outcomes of interest, while indoor play and screen-viewing were unfavorably associated.

Conclusion

The associations between movement behaviors and cognitive outcomes are multifaceted, influenced by specific domains of PA and SB. This study underscores the importance of participation in organized PA/sports, outdoor active play, and reading books, while ensuring adequate sleep and limiting screen viewing, to enhance cognitive outcomes. These findings underscore the need for further research into time-use trade-offs. Such studies could have major implications for revising current guidelines or strategies aimed at promoting healthier 24 h-movement behaviors in children.

Study registration

https://clinicaltrials.gov/, NCT01174875.

Associations of 24-hour movement guidelines adherence with fruit and vegetable intake in university students

Background

Unhealthy eating habits, such as low vegetable and fruit intake, are associated with many health problems. 24-h movement behaviors have been reported to be positively associated with numerous health-related outcomes. Despite the importance of these two modifiable lifestyle behaviors in building healthy habits in university students, there is a paucity of relevant research in this population. Therefore, this study aims to examine the correlation between compliance with 24-h movement guideline (24-h MG) and intake of fruits and vegetables (IFV) in Chinese university students.

Methods

This study investigated the relationship between the compliance with 24-h MG and IFV in 1,793 Chinese university students using a convenience sampling method online. Physical activity (PA) and sedentary behavior (SB) were assessed by the International Physical Activity Questionnaire-Short Form, while sleep was measured using the Pittsburgh Sleep Quality Index. The Chinese version of the Health Promoting Lifestyle Profile II was used to measure IFV. Generalized linear models were applied to examine the correlation between compliance with the 24-h MG and eating habits.

Results

The proportion of participants who routinely consumed vegetables and fruits was 24.6% and 43.1%, respectively, while the proportion of meeting the three 24-h MG and a combination of any two guidelines was 27.8% and 40.1%, respectively. Meeting all three guidelines was associated with a greater IFV intake compared to not meeting either guideline. Meeting all three guidelines (OR = 2.42 [1.63, 3.58]) and the combination of moderate to vigorous PA (MVPA) and sleep (OR = 2.06 [1.37, 3.10]) were positively associated with the frequency of vegetable consumption (p < 0.05). As well, meeting all three guidelines (OR = 2.06 [1.37, 3.10]), the combination of MVPA and sleep (OR = 1.72 [1.04, 2.84]), and sleep only (OR = 1.88 [1.21, 2.92]) were positively associated with fruits consumption (p < 0.05).

Conclusion

Almost a third of the university students met the three 24-h MG, and compliance with all three guidelines was associated with a higher frequency of IFV. Furthermore, meeting the sleep guideline alone or in conjunction with the PA, and meeting the entire 24-h MG was associated with greater consumption of fruits.

Exploring the mediating role of promoting school physical activity on the relationship between low socioeconomic status and academic achievement and school climate: evidence from 4,990 Chilean schools

There is evidence that promoting school physical activity (PSPA) benefits children and adolescents, but little is understood about how this promotion may relate to academic achievement and school climate across varying levels of socioeconomic status (SES). Hence, the study aimed to address this knowledge gap by examining two main objectives: (1) determining the association between PSPA and academic achievement and school climate according to schools' SES and (2) exploring the potential mediating role of PSPA in the relationship between schools' SES and academic achievement and school climate. This cross-sectional study at the school level focused on 4,990 schools (including public, subsidized, and private schools) that participated in the National Educational Study 2018 (Chile), which was applied to primary schoolchildren (4th grade, aged 8-10 years). Schools were divided into non-PSPA (n = 4,280) and PSPA (n = 710) during the year 2018. Changes in academic achievement from 2017 to 2018 and school climate were considered. PSPA was associated with improvements in maths (low-SES OR: 1.80, p < 0.001) and reading (middle-SES OR: 1.45, p = 0.029; low-SES OR: 1.47, p < 0.001). The indirect effect (IE) showed that PSPA partially mediated the relationship between SES and academic achievement in reading (IE = 1.017; SE = 0.12; 95%CI, -1.27, -0.77), maths (IE = -1.019; SE = 0.12; 95%CI, -1.25, -0.78), and school climate (IE = -0.46; SE = 0.52; 95%CI, -0.56, -0.35). In conclusion, PSPA was linked to positive changes in academic achievement, especially among low SES, and PSPA presented a potential mediating role in the relationship between SES of schools and academic achievement and school climate.

Dysexecutive symptomatology in everyday functioning and academic achievement in adolescents

Background

During the educational stage, academic achievement depends on various social, family, and personal factors. Among the latter, executive skills in everyday life play a significant role in dealing with the academic demands of adolescents. Therefore, the aim of this study is to ascertain the effects of executive symptomatology in everyday functioning on academic achievement in adolescents.

Method

The study involved 910 students aged between 13 and 15 years (M = 14.09, SD = 0.68) from both public and private schools in the Community of Madrid. The DEX, BDEFS-CA, and BRIEF-SR questionnaires were utilised to assess executive difficulties, while grades in language, mathematics, and natural sciences were used as a measure of academic achievement.

Results

The data revealed statistically significant differences in working memory, emotional control, materials organisation, and task completion. In relation to language and natural sciences subjects. In the case of mathematics, emotional control and task completion were significant variables.

Conclusion

Our results indicate that certain executive skills that are manifested in everyday life activities can contribute, albeit in a variable way, to academic achievement in the subjects studied. This aspect is relevant insofar as it allows us to develop preventive interventions based on the executive training of these everyday skills.

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.

Multimodal neuroimaging correlates of physical-cognitive covariation in Chilean adolescents. The Cogni-Action Project

Health-related behaviours have been related to brain structural features. In developing settings, such as Latin America, high social inequality has been inversely associated with several health-related behaviours affecting brain development. Understanding the relationship between health behaviours and brain structure in such settings is particularly important during adolescence when critical habits are acquired and ingrained. In this cross-sectional study, we carry out a multimodal analysis identifying a brain region associated with health-related behaviours (i.e., adiposity, fitness, sleep problems and others) and cognitive/academic performance, independent of socioeconomic status in a large sample of Chilean adolescents. Our findings suggest that the relationship between health behaviours and cognitive/academic performance involves a particular brain phenotype that could play a mediator role. These findings fill a significant gap in the literature, which has largely focused on developed countries and raise the possibility of promoting healthy behaviours in adolescence as a means to influence brain structure and thereby cognitive/academic achievement, independently of socioeconomic factors. By highlighting the potential impact on brain structure and cognitive/academic achievement, policymakers could design interventions that are more effective in reducing health disparities in developing countries.

24-hour movement behaviours and self-rated health in Chinese adolescents: a questionnaire-based survey in Eastern China

Objective

Although much evidence has demonstrated the benefits of adhering to the 24-hour movement guidelines, little is known about their association with self-rated health in adolescents. The objective of this study was to explore the association between adherence to the 24-hour movement guidelines (i.e., physical activity, screen time, and sleep) and self-rated health among Chinese adolescents aged 10-17 ages.

Methods

A convenient sample of 12 schools and their students were recruited for this cross-sectional study. Physical activity and screen time were assessed using a questionnaire based on the Health Behaviour in School-aged Children questionnaire, while sleep duration was used measured using the Pittsburgh Sleep Scale. Ordinal logistic regression was performed to examine the association between adherence to the 24-hour movement guidelines and self-rated health.

Results

Adolescents who adhered to more guidelines contained in the 24-hour movement guidelines reported better self-rated health. A dose-response association was observed, with the odds ratio (OR) for adhering to all three = 11.26, 95% CI [4.82-26.35]; OR for meeting two = 1.62, 95% CI [1.25-2.12]; OR for meeting one = 1.16, 95% CI [0.98-1.38]) indicating a higher probability of better self-rated health with increasing adherence. Regarding adherence to specific combination of 24-hour movement guidelines, positive associations were found for adhering to all three recommendations (OR = 11.95, 95% CI [5.06-28.19]), only MVPA (OR = 4.96, 95% CI [2.82-8.72]), MVPA + screen time (OR = 5.50, 95% CI [3.02-9.99]), and MVPA + sleep (OR = 4.63, 95% CI [2.52-8.51]).

Conclusion

This study provides evidence supporting the association between adherence to the 24-hour movement guidelines and better self-rated health among Chinese adolescents. Sufficient physical activity may be particularly important for promoting self-rated health in this population.

A Classroom-Based Intervention to Promote Physical Literacy in Children: ALPHYL Study Protocol

Physical literacy is crucial for children's appropriate development and physical, social and mental health. In a school setting, class-based physical activity (PA) interventions are considered to be appropriate programs to foster PA participation and cognitive development. The purpose of this project, named the Active Learning in PHYsical Literacy (ALPHYL) study, was to describe a multicomponent classroom-based physically-active learning randomised control trial (RCT) in primary school children. The main purpose was to promote children's physical literacy, academic achievement and cognitive function. The ALPHYL study is mainly based on physical literacy, active school models and the Supportive, Active, Autonomous, Fair and Enjoyable principles. The ALPHYL is an 8-10-week RCT to be conducted in six primary schools (12 classes) in Valencia (Spain) and its metropolitan area. Schools will be randomly assigned to the intervention or waiting-list control group. After a 30 h in-person training course for teachers and weekly meetings in the three months of resource preparation, the ALPHYL intervention will be conducted in physical education (PE) and non-PE lessons by teachers. The intervention consists of at least three daily sessions of physically active learning in addition to model-based PE teaching. Its feasibility will be evaluated weekly according to the Reach, Effectiveness, Adoption, Implementation and Maintenance framework. To assess its effectiveness, a pre-test, post-test and retention (8-10 weeks post-intervention) with primary outcomes (i.e., PA level, motor competence, perceived motor competence and PL, motivation, perceived social support, academic achievement and cognitive function), secondary outcomes and covariates will be collected.

Associations of meeting 24-h movement behavior guidelines with cognitive difficulty and social relationships in children and adolescents with attention deficit/hyperactive disorder

BACKGROUND

Evidence-based 24-h movement behavior (24-HMB) guidelines have been developed to integrate recommendations for the time spent on physical activity, sedentary behavior, and sleep. For children and adolescents, these 24-HMB guidelines recommend a maximum of two hours of recreational screen time (as part of sedentary behavior), a minimum of 60 min per day of moderate to vigorous physical activity (MVPA), and an age-appropriate sleep duration (9-11 h for 5 to 13-year-olds; 8-10 h for 14 to 17-year-olds). Although adherence to the guidelines has been associated with positive health outcomes, the effects of adhering to the 24-HMB recommendations have not been fully examined in children and adolescents with attention eficit/hyperactive disorder (ADHD). Therefore, this study examined potential associations between meeting the 24-HMB guidelines and indicators of cognitive and social difficulties in children and adolescents with ADHD.

METHODS

Cross-sectional data on 3470 children and adolescents with ADHD aged between 6 and 17 years was extracted from the National Survey for Children's Health (NSCH 2020). Adherence to 24-HMB guidelines comprised screen time, physical activity, and sleep. ADHD-related outcomes included four indicators; one relating to cognitive difficulties (i.e., serious difficulties in concentrating, remembering, or making decisions) and three indicators of social difficulties (i.e., difficulties in making or keeping friends, bullying others, being bullied). Logistic regression was performed to determine the associations between adherence to 24-HMB guidelines and the cognitive and social outcomes described above, while adjusting for confounders.

RESULTS

In total, 44.8% of participants met at least one movement behavior guideline, while only 5.7% met all three. Adjusted logistic regressions further showed that meeting all three guidelines was associated with lower odds of cognitive difficulties in relation to none of the guidelines, but the strongest model included only screen time and physical activity as predictors (OR = 0.26, 95% CI 0.12-0.53, p < .001). For social relationships, meeting all three guidelines was associated with lower odds of difficulty keeping friends (OR = 0.46, 95% CI 0.21-0.97, p = .04) in relation to none of the guidelines. Meeting the guideline for screen time was associated with lower odds of being bullied (OR = 0.61, 95% CI 0.39-0.97, p = .04) in relation to none of the guidelines. While screen time only, sleep only and the combination of both were associated with lower odds of bullying others, sleep alone was the strongest predictor (OR = 0.44, 95% CI 0.26-0.76, p = .003) in relation to none of the guidelines.

CONCLUSION

Meeting 24-HMB guidelines was associated with reduced likelihood of cognitive and social difficulties in children and adolescents with ADHD. These findings highlight the importance of adhering to healthy lifestyle behaviors as outlined in the 24-HMB recommendations with regard to cognitive and social difficulties in children and adolescents with ADHD. These results need to be confirmed by longitudinal and interventional studies with a large sample size.

Sedentary behaviours and their relationship with academic performance in adolescents: A mediation analysis

The present research aims to examine the relationship between the four dimensions of sedentary behaviours and academic performance, as well as to test the association between sedentary behaviours and academic performance in boys and girls in a sample of Spanish adolescents. A total of 2,216 adolescents aged 11 to 16 years old, both males (13.30 ± 0.92) and females (13.06 ± 0.86), participated. Sleep duration, physical activity, and sedentary behaviours were measured through questionnaires. Academic performance was assessed with students´ marks. Potential confounders such as sex, age, socioeconomic status, and cardiorespiratory fitness were also measured. Descriptive analysis, correlation analysis, analysis of differences, and multiple mediation analysis were conducted. It was observed that girls spend more time on sedentary educational or social behaviours, while boys spend much more time on screen time. Sedentary behaviours such as educational time, screen time, and relaxing time were associated with academic performance. Specifically, educational time appears to be positively related to academic performance. Nevertheless, screen time and relaxing time were negatively associated with academic performance. The multiple mediation analysis revealed that screen time was the most negative behaviour on academic performance. The outcomes are discussed to improve knowledge about sedentary behaviours and academic performance.

Prevalence and correlates of compliance with 24-h movement guidelines among children from urban and rural Kenya-The Kenya-LINX project

BACKGROUND

Like many countries in sub-Saharan Africa, Kenya has experienced rapid urbanization in recent years. Despite the distinct socioeconomic and environmental differences, few studies have examined the adherence to movement guidelines in urban and rural areas. This cross-sectional study aimed at examining compliance to the 24-hour movement guidelines and their correlates among children from urban and rural Kenya.

METHOD

Children (n = 539) aged 11.1 ± 0.8 years (52% female) were recruited from 8 urban and 8 rural private and public schools in Kenya. Physical activity (PA) and sleep duration were estimated using 24-h raw data from wrist-worn accelerometers. Screen time (ST) and potential correlates were self- reported. Multi-level logistic regression was applied to identify correlates of adherence to combined and individual movement guidelines.

RESULTS

Compliance with the combined movement guidelines was low overall (7%), and higher among rural (10%) than urban (5%) children. Seventy-six percent of rural children met the individual PA guidelines compared to 60% urban children while more rural children also met sleep guidelines (27% vs 14%). The odds of meeting the combined movement guidelines reduced with age (OR = 0.55, 95% CI = 0.35-0.87, p = 0.01), was greater among those who could swim (OR = 3.27, 95% CI = 1.09-9.83, p = 0.04), and among those who did not engage in ST before school (OR = 4.40, 95% CI = 1.81-10.68, p<0.01). The odds of meeting PA guidelines increased with the number of weekly physical education sessions provided at school (OR = 2.1, 95% CI = 1.36-3.21, p<0.01) and was greater among children who spent their lunch break walking (OR = 2.52, 95% CI = 1.15-5.55, p = 0.02) or running relative to those who spent it sitting (OR = 2.33, 95% CI = 1.27-4.27, p = 0.01).

CONCLUSIONS

Prevalence of meeting movement guidelines among Kenyan children is low and of greatest concern in urban areas. Several correlates were identified, particularly influential were features of the school day, School is thus a significant setting to promote a healthy balance between sleep, sedentary time, and PA.

Interactive Associations between Physical Activity and Sleep Duration in Relation to Adolescent Academic Achievement

PURPOSE

The present study aimed to examine independent and interactive associations between physical activity and sleep duration with adolescent academic achievement.

METHODS

This cross-sectional study used data from the 2019 cycle of the US-based Youth Risk Behavior Surveillance System. A total of 13,677 American adolescents in grades 9 through 12 (M_AGE = 16.06 ± 1.24 years; 50.9% female) self-reported their sleep and physical activity behavior as well as their grades. Linear regression models fit with cubic splines were computed to capture potential non-linear associations.

RESULTS

Findings for the independent effect models revealed significant curvilinear relationships between physical activity and sleep with academic achievement wherein optimal grades were associated with 7-9 h/night of sleep and 5-7 days/week of physical activity. A significant physical activity by sleep interaction was also observed for academic achievement, which demonstrated that the association between sleep duration and academic achievement is not uniform across levels of physical activity engagement, and tradeoffs may exist.

CONCLUSIONS

Overall, the results help to identify different combinations of physical activity and sleep behavior associated with optimal academic achievement and suggest that a one-size-fits-all approach to physical activity and sleep recommendations may not be adequate for promoting academic achievement during adolescence.

Associations of Passive and Mentally Active Screen Time With Perceived School Performance of 197,439 Adolescents Across 38 Countries

OBJECTIVE

To examine the associations of passive (ie, television) and active (ie, electronic games, computer use) screen time (ST) with perceived school performance of adolescents across gender.

METHODS

Data were from the 2014 Health Behaviour in School-aged Children survey conducted across 38 European countries and Canada. Perceived school performance was assessed using an item and dichotomized as high (good/very good) versus the remainder (average/below-average as reference). Participants reported hours per day of time spent watching television, playing electronic games, and using a computer in their free time. Multilevel logistic regression was used to estimate the associations.

RESULTS

A total of 197,439 adolescents (average age 13.6 [standard deviation 1.63] years; 51% girls) were analyzed. Multivariable modeling showed that engaging in >2 h/d of ST was progressively and adversely associated with high performance in both boys and girls. Adolescents reporting >4 h/d of television time (≤1 h/d as reference) had 32% lower odds in boys (odds ratio [OR] 0.68; 95% confidence interval [CI]: 0.65-0.71) and 39% lower odds in girls (OR 0.61; 95% CI, 0.58-0.65) of reporting high performance. Playing electronic games for >4 h/d was associated with high performance with odds being 38% lower in boys (OR 0.62; 95% CI, 0.59-0.66) and 45% lower in girls (OR 0.55; 95% CI, 0.52-0.57). Sex differences in the estimates were mixed.

CONCLUSIONS

High screen use, whether active or passive, was adversely associated with perceived high school performance, with association estimates being slightly stronger in girls than boys, and for mentally active than passive screen use. Discouraging high levels of screen use of any type could be beneficial to school performance.

Adolescents' Physical Activity and Depressive Symptoms: A Psychosocial Mechanism

Guided by the Theory of Planned Behavior (TPB; Ajzen, 1991), this study aimed to test a hypothesized path model of TPB variables (i.e., attitude toward behavior, subjective norm, perceived behavioral control, and intention) with physical activity (PA) and depressive symptoms. A total of 792 Chinese adolescents (M_age = 16.9; SD = 0.82; 54.5% females) completed previously validated questionnaires assessing their TPB variables, PA, and depressive symptoms. Correlation analysis revealed TPB variables were positively associated with PA (p < 0.01), and negatively correlated to depressive symptoms (p < 0.01). The path analyses indicated that the hypothesized model produces a goodness of fit (χ²/df = 16.14/5, CFI = 0.99, RMSEA = 0.06). The findings support the theoretical tenets of TPB and provide empirical evidence of the psychosocial mechanism of PA and depressive symptoms in Chinese adolescents. It suggests that building PA intervention strategies while considering the TPB framework may promote adolescents' physical and mental health.