BACKGROUND: The main aim of the study is to examine changes in the prevalence of obesity in Czech adolescents between 2018 and 2022 and its current non-genetic correlates with respect to the adolescents' families'socioeconomic status (SES) in 2022. METHODS: The sample of 24,535 adolescents (n = 11,629/12,9062018/2022; boys: 50.4/50.6%2018/2022) aged 10.5-16.5 years that was analysed was drawn from two nationally representative cohorts of Czech youngsters from the last two cycles of the Health Behaviour in School-aged Children (HBSC) online questionnaire survey from 2018 to 2022. Obesity is represented by the > 97th percentile interval on the World Health Organization Body Mass Index percentile chart, with distinctions by sex and the age of adolescents. The differences in the prevalence of obesity between boys and girls from all SES family categories in 2018 and 2022 were tested using a chi-square test (χ2). Multiple logistic regression analysis with repeated measures was used to analyse correlates of obesity in 2022. RESULTS: Between 2018 and 2022, there was no significant difference in the prevalence of obesity in girls or boys in any of the SES categories of families. Adolescents from low-SES families have the highest prevalence of obesity, 11% for boys and 5.8% for girls, significantly higher (p < .001) than its prevalence among adolescents from high-SES families, by + 4.8% points for boys and + 3.9% points for girls. Among adolescents from low-SES families, individuals who engaged in moderate-to-vigorous physical activity (PA) daily (p < .005) or vigorous PA three times per week (p < .05) were significantly less likely to be obese than their less active peers. Skipping breakfast significantly (p < .05) increased the odds of obesity, but only among adolescents from low-SES families. Shorter screen time (ST) significantly (p < .05) reduced the odds of obesity for all categories of adolescent SES. CONCLUSIONS: Obesity is most pronounced in adolescents from low-SES families as a result of a long-term positive energy balance mediated by unbalanced behaviour. Significantly lower odds of obesity in adolescents from low-SES families were confirmed to be associated with regular practice of the recommended PA, shorter ST, and not skipping breakfast.

• Klíčová slova
• Eating habits, HBSC study, Obesity, Physical activity, Sleeping, Socioeconomic status,
• MeSH
• dítě MeSH
• index tělesné hmotnosti MeSH
• lidé MeSH
• mladiství MeSH
• nadváha epidemiologie   MeSH
• obezita * epidemiologie   genetika   MeSH
• prevalence MeSH
• školy * MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH

OBJECTIVE: Long-term isolation, including lockdowns and quarantines, may have a distressing effect on anyone experiencing it. Adolescent brain architecture is very sensitive to environmental adversities, and the mental health development of adolescents may be particularly vulnerable during the pandemic era. In order to better understand the triggers for perceived adolescent stress (PSS) during the COVID-19 lockdown, the present study aimed to assess the effects of social well-being and changes in time use during the lockdown, as well as the family COVID experience of adolescents. METHODS: The sample for this study comprised n = 3,440 adolescents (54.2% girls; mean age = 13.5 ± 1.6 years). Bayesian correlations between PSS, health and well-being variables were assessed. PSS was then modeled as an outcome variable in a series of nested Bayesian multilevel regression models. RESULTS: The negative impact of the COVID-19 lockdown was more apparent in girls. PSS was moderately correlated with adolescent health and well-being. The strongest predictor of higher level of PSS was frequent feeling of loneliness. On the contrary, lower level of PSS was most associated with having someone to talk to. CONCLUSION: Long-term social isolation of adolescents could be harmful to their mental health. Psychological coping strategies to prevent the consequences of social isolation and development of mental health problems should be promoted on the individual, family, and even community level.

• Klíčová slova
• Bayesian multilevel regression, COVID-19 lockdown, HBSC, adolescent, perceived stress,
• Publikační typ
• časopisecké články MeSH

Life satisfaction, an important precursor of adolescents' well-being, is linked to daily activities. Substantial changes have been noted in adolescents' daily activities over the years, raising the question of possible consequences for life satisfaction. This study aimed to explore changes in adolescents' life satisfaction and their time spent on daily activities (sleeping, engaging in sports, online gaming, school commuting, time spent at school) and further investigate the associations between adolescents' life satisfaction and these daily activities. The sample comprised 2715 adolescents from birth cohorts surveyed at four time points between 1992 and 2019. Participants were administered the Daily Activities Inventory and the Berne Questionnaire on Adolescents' Well-Being. Robust ANOVA with post hoc tests and spline regression were employed. We found cohort differences in sleep duration (8.6 h a day on average in 1992 and 7.5 in 2019). Sleep duration of 8 h and 1 h of sports activities had a beneficial effect on life satisfaction, while more than 1 h of online gaming had a negative impact. Neither school attendance nor commuting to school was associated with adolescents' life satisfaction. The results of this study can inform public-health policies to promote sleeping and sports habits in adolescence.

• Klíčová slova
• adolescents, birth cohorts, daily activities, leisure, life satisfaction, online gaming, school commuting, sleep duration, sports, time spent at school,
• MeSH
• lidé MeSH
• mladiství MeSH
• osobní uspokojení * MeSH
• průzkumy a dotazníky MeSH
• školy MeSH
• spánek * MeSH
• Check Tag
• lidé MeSH
• mladiství MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH