@article{53785,
abstract = {{AbstractDue to the lockdown of schools as one of the COVID-19 control measures, adolescents have had the opportunity to re-organise their daily lives; e.g. some of them have adapted their bedtimes to the new situation during the lockdown in favour of their own chronotype. Hence, we investigated differences in chronobiological characteristics (e.g., the midpoint of sleep, sleep duration or social jetlag (SJL); i.e., a discrepancy between biological and social timing) before and during the pandemic lockdown to examine potential changes. We asked participants from the ongoing open cohort Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) study to fill out the Munich Chronotype Questionnaire during the COVID-19 lockdown and received the information of participants (n = 66) during the pandemic. A reference group matched for age, season, and sex was randomly selected from the DONALD study to assess participants’ chronobiological characteristics prior to (n = 132) the pandemic. Analyses of covariance were applied to examine differences between the two groups reflecting the situation before and during the COVID-19 pandemic. Participants were aged 9–18 years (52% males). In the current examination, average sleep duration across the week was higher among adolescents during the pandemic (β = 00:30; p = 0.0006) and social jetlag was significantly lower (β = −00:39; p < 0.0001). Conclusion: Our results showed that the COVID-19 lockdown enabled adolescents to adapt their sleeping habits according to their naturally late chronotype, which led to a significant reduction in SJL. These observations are likely to be explained by the effect of school closure.
What is Known:• Under ‘normal conditions’ without pandemic lockdowns, adolescents accumulate a lack of sleep due to social obligations such as school starts, resulting in social jetlag.• A late chronotype or exposure to social jetlag is a known risk factor for the development of chronic diseases.
What is New:• The COVID-19 lockdown represents a ‘natural experiment’ that enables adolescents to adhere to their internal biological clock. Without the usual social obligations, social jetlag can be significantly reduced.
}},
author = {{Perrar, Ines and Alexy, Ute and Jankovic, Nicole}},
issn = {{1432-1076}},
journal = {{European Journal of Pediatrics}},
number = {{6}},
pages = {{2801--2805}},
publisher = {{Springer Science and Business Media LLC}},
title = {{{Chronobiological changes due to school closures during the COVID-19 pandemic among adolescents in the DOrtmund Nutritional and Anthropometric Longitudinally Designed cohort study}}},
doi = {{10.1007/s00431-023-04963-9}},
volume = {{182}},
year = {{2023}},
}
@article{60095,
abstract = {{AbstractEndurance training has been shown to be effective in treating adolescents with major depressive disorder (MDD). To integrate endurance training into the therapeutic setting and the adolescents' daily lives, the current performance status of the adolescents should be accurately assessed. This study aims to examine adolescents with MDD concerning exhaustion criteria during a cardiopulmonary exercise test (CPET), as well as to compare the values obtained thereon with sex- and age-related control values. The study included a retrospective examination of exhaustion criteria ((i) oxygen consumption (V̇O2) plateau, (ii) peak respiratory exchange ratio (RERpeak) > 1.0, (iii) peak heart rate (HRpeak) ≥ 95% of the age-predicted maximal HR, and (iv) peak blood lactate concentration (BLCpeak) > 8.0 mmol⋅L−1) during a graded CPET on a cycle ergometer in adolescents with MDD (n = 57). Subsequently, maximal V̇O2, peak minute ventilation, V̇O2 at the first ventilatory threshold, and peak work rate of participants who met at least two of four criteria were compared with published control values using an independent-sample t-test. Thirty-three percent of the total population achieved a V̇O2 plateau and 75% a RERpeak > 1.0. The HR and BLC criteria were met by 19% and 22%, respectively. T-test results revealed significant differences between adolescents with MDD and control values for all outcomes. Adolescents with MDD achieved between 56% and 83% of control values. Conclusions: The study shows that compared with control values, fewer adolescents with MDD achieve the exhaustion criteria on a CPET and adolescents with MDD have significantly lower cardiorespiratory fitness. Clinical trial registration: No. U1111-1145–1854.
What is Known:• It is already known that endurance training has a positive effect on depressive symptoms.
What is New:• A relevant proportion of adolescents with major depressive disorder do not achieve their V̇O2max during a graded cardiopulmonary exercise test.• Adolescents with major depressive disorder have significantly lower cardiorespiratory fitness compared to sex- and age-related control values.
}},
author = {{Wenzel, Charlotte and Bongers, Bart Chateau and Schlagheck, Marit Lea and Reis, Daniela and Reinhard, Franziska and Schmidt, Peter and Bernitzki, Stefan and Oberste, Max and Wunram, Heidrun Lioba and Zimmer, Philipp and Fricke, Oliver}},
issn = {{1432-1076}},
journal = {{European Journal of Pediatrics}},
number = {{1}},
pages = {{379--388}},
publisher = {{Springer Science and Business Media LLC}},
title = {{{Validation of the maximal cardiopulmonary exercise test in adolescents with major depressive disorder and comparison of cardiorespiratory fitness with sex- and age-related control values}}},
doi = {{10.1007/s00431-023-05304-6}},
volume = {{183}},
year = {{2023}},
}