Sleep duration and quality during the COVID-19 pandemic and the association with physical activity and screen time among Brazilian college students.

BACKGROUND: As a result of social isolation during the COVID-19 pandemic, changes in sleep patterns have been observed in many countries, as well as changes in physical activity and screen time. The objective was to investigate sleep duration and quality during the COVID-19 pandemic and its association with physical activity and screen time. METHODS: Cross-sectional study with students from a University in Rio de Janeiro who answered an online questionnaire between August 2020 and March 2021. Physical activity was assessed using IPAQ-SF. Sleep was investigated based on questions about duration and sleep quality change, and screen time through self-reported questions. Multinomial logistic regression was performed to assess the association between physical activity and screen time with sleep duration and quality. Secondary analyses investigated the influence of the isolation time on this association. The confounding factors used were diagnosis of COVID-19, time of isolation, anxiety, depression, skin color, and gender. RESULTS: A total of 771 college students with a mean age of 24.5 years (±8.6) answered the questionnaire. About 75% reported more than 8 h of screen time per day and 49.8% were physically inactive. Regarding sleep, 54.9% had worsening sleep, while 40.6% had inadequate sleep duration during the pandemic. Physical activity was associated with improved sleep quality (Odds ratio (OR) 1.72; confidence interval (95% CI) 1.05-2.97). Also, physically active students who spent more than 14 weeks in social isolation demonstrated improved sleep quality (OR 1.99; 95% CI 1.02-3.78) compared to physically inactive individuals. No association was observed for sleep duration. No association was observed between screen time and sleep quality, or sleep duration. CONCLUSION: During the COVID-19 pandemic, there was considerable worsening of sleep quality, and physical activity was positively associated with improved sleep quality.

Psychological Aspects, Physical Activity Levels and Overweight Concerns: A Cross-over Study of Brazilian Adolescents.

Introduction: This study aims to identify levels of anxiety, depression, body weight, and levels of physical activity, as well as to verify possible associations among these variables in Brazilian adolescents. It is a cross-sectional study with a convenience sample of 291 Brazilian adolescents aged 13 to 15 years old (13.75±0.80 years old). Methods: Researchers assessed students by filling out questionnaires of anxiety and depression symptoms, as well as the level of physical activity and checking anthropometric measures. Parametric and non-parametric statistics were used to compare groups divided by psychological, physical and overweight factors for boys and girls, adopting a significance level of 95%. Results: Results showed higher waist circumference and physical activity levels for boys (p<0.01) and higher scores for anxiety and depressive symptoms questionnaires for girls (p<0.01). In addition, a low prevalence of depression was observed in boys (0.69%/CI0.03-4.36). For anxiety and depression variables in males and females with and without overweight and physically active and inactive, there were significant differences between groups (p < 0.05), but not within groups. Conclusion: The identification of a higher prevalence of girls with anxiety and depression was observed in this study and reinforced this information already demonstrated in the scientific literature. In general, the prevalence of depression was low in boys, while the prevalence of overweight, sedentary lifestyle, anxiety and depression were higher in girls.

Can transcranial direct current stimulation on the dorsolateral prefrontal cortex improves balance and functional mobility in Parkinson's disease?

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique increasingly explored for Parkinson's disease (PD). Although evidence is still inconsistent, there are preliminary findings suggesting its efficacy to improve motor function in individuals with PD, as the role of secondary motor areas remains unclear. The goal of this study was to investigate the effects of left dorsolateral prefrontal cortex (DLPFC) tDCS on balance and functional mobility of individuals with PD. Seventeen individuals with PD, on-medication, aged between 40 and 90 years were recruited to enroll in a double-blind, randomized, cross-over trial. Each participant completed two conditions at least 48h apart, namely anodal-tDCS and sham-tDCS (placebo). The a-tDCS condition targeted the left DLPC (F3) and was applied during 20min using a 2mA current intensity. In the sham-tDCS condition, electrode position remained the same but the stimulator was turned off after 30s. Functional mobility and balance were assessed using the Berg Balance Scale, Dynamic Gait Index and Timed Up and Go. There were significant differences between conditions on all outcome measures, as the a-tDCS condition was associated with better performance in comparison to the sham condition (p<0.05). Our findings suggest that a-tDCS on the left DLPFC improves balance and functional mobility in comparison to sham-tDCS. Compensatory mechanisms that support motor function in individuals with PD may have been enhanced by a-tDCS on the DLPFC, leading to improved functional mobility and balance. Future trials should explore left DLPFC stimulation with larger samples and compare t-DCS protocols targeting several brain regions.