Changes in Canadian Adolescent Time Use and Movement Guidelines During the Early COVID-19 Outbreak: A Longitudinal Prospective Natural Experiment Design

Association between movement behaviors and depression among vocational school students with different sleep duration - a study based on the isotemporal substitution model

The isotemporal substitution model can be used to explore the impact of the isotemporal substitution of different behaviors on human health. The association between sleep duration and mental health may be non-linear, but the relationship between the isotemporal substitution of movement behaviors and mental health in different sleep duration groups has not been explored. A questionnaire survey was conducted among Grade 1-3 students in 14 vocational schools in China, and 8149 valid questionnaires were obtained, of which 58.80% were in sleep-insufficient group, and 32.56% were detected with depression symptoms. The isotemporal substitution model was used for analysis. In the sleep-insufficient group, substituting 10 minutes/day of vigorous physical activity (β=-0.318, 95%I = -0.498~-0.138), walking (β=-0.254, 95%I = -0.381~-0.126) and sedentary behavior (β=-0.234, 95%I = -0.337~-0.130) with isotemporal moderate physical activity, or substituting vigorous physical activity (β=-0.465, 95%I = -0.577~-0.353), moderate physical activity (β=-0.147, 95%I = -0.263~-0.031), walking (β=-0.400,95%I = -0.476~-0.324) and sedentary behavior (β=-0.380,95%I = -0.434~-0.327) with isotemporal sleep, were negatively associated with depression; and substituting moderate physical activity (β = 0.318, 95%CI = 0.138 ~ 0.498) and sleep (β = 0.465, 95%CI = 0.353 ~ 0.577) with isotemporal vigorous physical activity was positively associated with depression. In the sleep-sufficient group, replacing sedentary behavior (β=-0.129, 95%I = -0.244~-0.013) with equivalent moderate physical activity was negatively associated with depression; replacing moderate physical activity (β = 0.219, 95%CI = 0.101 ~ 0.338), walking (β = 0.112, 95%CI = 0.040 ~ 0.185) and sedentary behavior (β = 0.091, 95%CI = 0.058 ~ 0.124) with equivalent sleep was positively associated with depression. For the sleep-insufficient group, substituting vigorous physical activity, walking, and sedentary behavior with isotemporal moderate physical activity and sleep had greater negative association with depression than the sleep-sufficient group. In conclusion, for the sleep-insufficient group, the substitution that was largest negatively associated with depression was sleep for other behaviors, and for sleep-sufficient group it was moderate physical activity for other behaviors. In future interventions, the sleep-insufficient group may achieve greater effects than the sleep-sufficient group if they use moderate physical activity and sleep instead of other behaviors.

Social determinants of health at multiple socio-ecological levels and sleep health in adolescents: A scoping review

Heightened sleep disturbances occur in adolescence, yet existing research has predominantly focused on individual factors linked to poor sleep and a limited set of sleep outcomes, such as sleep duration and timing. This scoping review aimed to identify the multilevel social determinants of adolescent sleep health across domains, including regularity, satisfaction/quality, alertness/sleepiness, timing, efficiency/continuity, duration, and behavior. Social determinants of health (SDoH) were categorized through a socio-ecological lens, while sleep health domains were aligned with the RU-SATED and Peds B-SATED sleep health frameworks. A systematic database search resulted in 57 studies of non-clinical adolescent and young adult populations (age 10-24 y) in North America, published between 2014 and 2022. Research gaps include 1) absence of other sleep health domains other than duration which is predicated on the included studies using a limited set of sleep outcome measures rather than a more comprehensive measurement strategy that align with the multifaceted domains of sleep health, and 2) inconsistent terminology and/or absent conceptual and operational definitions of subjective sleep reports. The findings highlight the multilevel SDoH that influence adolescent sleep health, underscoring the need for more comprehensive research. Such efforts will facilitate the development of interventions focused on fostering optimal adolescent sleep health this populations.

Comparison of Estonian Schoolchildren's Physical Activity and Fitness Indicators before and after the COVID-19 Pandemic's Period of Restricted Mobility

It is recognized that the time adolescents spend on physical activity, and the corresponding physical fitness indicators, have diminished over time. However, the exact impact of the COVID-19 pandemic restriction period on physical activity and health-related physical fitness indicators remains unclear. This study sought to determine if and to what degree the primary indicators of physical activity (exercise frequency, exercise intensity, and outdoor physical activity) and health-related physical fitness (strength and endurance) among schoolchildren have shifted, by comparing data from before and after the coronavirus pandemic period. Students aged 12-17 years took part in the study. The physical activity questionnaire and fitness tests were conducted in the autumn of 2017 and spring of 2022. The main results show that moderate- and vigorous-intensity physical activity time and time spent actively outdoors have decreased among adolescents (p < 0.05). There were no significant changes in exercise frequency (p > 0.05). However, there was a statistically significant decline in strength (standing broad jump, bent arm hang) (p < 0.05) and endurance (20 m shuttle run, curl-up) (p < 0.01) when comparing results from before and after the COVID-19 pandemic restriction period. In conclusion, restricted mobility had the greatest impact on the time spent outdoors and, in turn, on physical fitness.

Evolution of Sleep Duration and Screen Time Between 2018 and 2022 Among Canadian Adolescents: Evidence of Drifts Accompanying the COVID-19 Pandemic

PURPOSE

We quantified the joint evolution of sleep duration and screen time between 2018 and 2022 in a large sample of adolescents from Quebec, Canada, to ascertain changes that occurred during the COVID-19 pandemic.

METHODS

A natural experiment design was used to compare variations from year to year and in association with the pandemic outbreak. Using structural equation modeling on data collected between 2018 and 2022 among adolescents attending 63 high schools, we analyzed the joint evolution of sleep duration and screen time while adjusting for previous year values, concurrent flourishing score, sex, age, and family level of material deprivation.

RESULTS

A total of 28,307 adolescents, aged on average 14.9 years, were included in the analyses. Between 2019 and 2022, sleep duration increased by 9.6 (5.7, 13.5) minutes and screen time by 129.2 (120.5, 138.0) minutes on average. In 2022, the adolescents spent almost equal amounts of time sleeping and using screens. Lower flourishing scores were associated with shorter sleep duration and lengthier screen time. Girls' screen time became similar to boys' over time.

DISCUSSION

Adolescents now spend almost equal amounts of time sleeping and using screens, a situation that calls for urgent public health actions. These findings highlight the importance of tracking changes in adolescents' behaviours over time, to design and implement interventions adapted to the changing health needs of different groups.

Daily experiences and adolescent affective wellbeing during the COVID-19 pandemic: The CHESS model

The COVID-19 pandemic resulted in adolescents' increased exposure to daily experiences of risk factors for depression and anxiety (e.g., loneliness). Intensive longitudinal studies examining daily experiences during the pandemic have revealed short-term and long-term consequences on youth mental health. Although evidence suggests small average increases in adolescent depression and anxiety, most of the story is in variability: increases are higher for youth and families with greater pre-existing mental health vulnerabilities and fewer socioeconomic resources, whereas increases are lower when social or financial support and positive coping and health behaviors are available and employed. Public health and economic policies should be mindful of youth mental health risks and actively promote known mental health supports, including family economic resources, access to mental healthcare, and social connection.

Sleep duration change among adolescents in Canada: Examining the impact of COVID-19 in worsening inequity

Purpose

The purpose of this study was to assess if adolescent sub-populations in Canada (i.e., based on race/ethnicity, sex/gender, socioeconomic status, and urbanicity groups) experienced a larger change in sleep duration and guideline adherence between 2019 and 2020 (pre-pandemic) and the 2020-2021 (mid-pandemic) school years.

Methods

Longitudinally linked data from 2019 to 2020 (pre-pandemic) and 2020-2021 (mid-pandemic) of a prospective cohort study of secondary school students (M = 14.2, SD = 1.3 years, N = 8209) in Canada were used for analyses. Regression modelling tested the main effects of race/ethnicity, sex/gender, socioeconomic status, and urbanicity on changes in sleep duration as well as adherence to Canada's 24-h Movement Guidelines for sleep (8-10 h/night). Interactions between identity variables (race/ethnicity or sex/gender) and other main effect variables were subsequently tested.

Results

Females gained more sleep (4.5 [1.5, 7.5] min/day more) and increased guideline adherence (AOR = 1.16 [1.04, 1.30] than males on average. Asian race/ethnic identity was associated with less sleep gain than White identity -10.1 [-19.4, -0.8], but not guideline adherence. Individuals in large urban areas gained less sleep and adhered less to guidelines than individuals from any other level of urbanicity (-21.4 [-38.5, -4.2] to -15.5 [-30.7, -0.2] min/day). Higher individual SES scores were associated with greater sleep gain (linear trend: 11.16 [1.2-21.1]). The discrepancies in sleep gain and guideline adherence between males and females were significantly modified by race/ethnicity and urbanicity.

Discussion

Increases in sleep duration may be one of the few benefits to adolescents during the COVID-19 pandemic but were not equally distributed across sub-populations. Efforts to promote better sleep adherence may need to account for sex/gender differences, especially in less urbanized areas and certain racial/ethnic groups.

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.

The association of physical activity, sleep, and screen time with mental health in Canadian adolescents during the COVID-19 pandemic: A longitudinal isotemporal substitution analysis

BACKGROUND

The impact of COVID-19 on adolescent mental health is a global concern. Increased screen time and reduced physical activity due to the lockdown measures have been linked to detrimental mental health outcomes; however, the literature remains limited by cross-sectional and retrospective designs, and consideration of behaviours in isolation. Prospective evidence is necessary to examine whether moderate-to-vigorous physical activity (MVPA), sleep and screen time influenced changes in mental health.

METHOD

Analyses used data from a prospective cohort study of secondary school students in Canada with baseline data from the 2018-2019 school year and linked follow-up data from online surveys completed during the initial COVID-19 outbreak (May-July 2020). Multilevel linear regression models were used to evaluate the within- and between-person isotemporal substitution effects of sleep, MVPA and screen time behaviours on depression, anxiety, subjective well-being, and trait emotional dysregulation.

RESULTS

Linked longitudinal data from 2645 students attending 44 schools were available. Between-person effects indicated that individuals who engaged in more MVPA and sleep while minimizing screen time had lower depression scores, less severe emotional dysregulation, and better subjective well-being. While controlling for between-person effects, within-person year-on-year change suggests those who increased screen time while decreasing either MVPA or sleep experienced mental health decline on all outcomes.

CONCLUSION

MVPA and sleep were associated with youth mental health during the early COVID-19 lockdown. Increasing MVPA and sleep (or at least mitigating the increase of screen time) compared to the prior year was associated with better mental health during the early pandemic. A limitation to consider is that the screen time measure represents a combination of screen behaviours, and effects of replacing screen time may have varied if distinctions were made.