Player Chronotype Does Not Affect In-Game Performance during the Evening (>18:00 h) in Professional Male Basketball Players

Sport-specific skills display diurnal variation across various team sports such as badminton and tennis serving accuracy and soccer dribbling, volleying, and chipping execution. However, the effects of athlete chronotype on in-game sport-specific skill performance according to time of day across team sports is not well understood. Therefore, the aim of this study was to identify the effect of player chronotype on in-game basketball performance during evening games. Professional male basketball players (n = 11) completed a morningness–eveningness questionnaire and were categorized according to chronotype (morning-type: n = 4; neither-type: n = 6; evening-type: n = 1). Box score data from the 2019/20 season were utilized to determine individual in-game performance during evening games played after 18:00 h. Composite metrics (i.e., effective field goal percentage, offensive rating, defensive rating, and player efficiency) were used as indicators of player performance. Non-significant (p ≥ 0.21) differences were evident between M-types and N-types for most performance measures. Small to very large effects were observed in the number of rebounds favoring M-types, and three-point shots attempted and made, assists, and steals favored N-types. In-game performance appeared to not be affected by chronotype (i.e., M-type vs. N-type) in evening games among professional male basketball players. The lack of observed effect between chronotype and in-game performance suggest coaching staff may not need to consider player chronotype when developing a match strategy or assigning player roles if largely dealing with M-types and N-types. However, to ensure the greatest specificity, coaching staff may endeavor to schedule habitual training times in line with that of competition in an effort to align player circadian rhythms to games.

Sleep–wake rhythm and its association with lifestyle, health-related quality of life and academic performance among Japanese nursing students: a cross-sectional study

Background Young adults are likely to have activities and go to bed late at night due to their age-dependent delayed endogenous circadian clock. The purpose of the present study was to clarify sleep–wake rhythm and its association with lifestyle, health-related quality of life, and academic performance among nursing students. Methods Self-reported questionnaires were distributed to undergraduate nursing students at six universities in Japan. Sleep–wake rhythm was assessed using the morningness-eveningness questionnaire. A quantitative design using the generalized linear mixed effect model was utilized to identify the factors related to the evening type among female nursing students (n = 447). Results About 18% of the participants were identified as the evening type. Evening type was associated with living alone, part-time job, and club activity. Sleep duration on weekdays was shorter, meal time duration was the shortest, and the percentages of students who skipped meals and those who gained body weight were higher in the evening type than in the morning type and intermediate type. Mental health-related quality of life was lower in the intermediate type and evening type than in the morning type, while there was no difference in physical health-related quality of life among these groups. The percentages of the nursing students who have experienced absence, tardiness, falling asleep during class, and/or interference with academic achievement were higher in the evening type than in other groups. Conclusions The present study has important implications for nursing students’ biological characteristics and lifestyle, which are associated with their health-related quality of life and academic performance.

Circadian Characteristics in Patients under Treatment for Substance Use Disorders and Severe Mental Illness (Schizophrenia, Major Depression and Bipolar Disorder)

Dual disorders (substance use and mental illness comorbidity) are a condition that has been strongly associated with severe symptomatology and clinical complications. The study of circadian characteristics in patients with Severe Mental Illness or Substance Use Disorder (SUD) has shown that such variables are related with mood symptoms and worse recovery. In absence of studies about circadian characteristics in patients with dual disorders we examined a sample of 114 male participants with SUD and comorbid Schizophrenia (SZ+; n = 38), Bipolar Disorder (BD+; n = 36) and Major Depressive Disorder (MDD+; n = 40). The possible differences in the sample of patients according to their psychiatric diagnosis, circadian functioning with recordings of distal skin temperature during 48 h (Thermochron iButton®), circadian typology and sleep-wake schedules were explored. MDD+ patients were more morning-type, while SZ+ and BD+ had an intermediate-type; the morning-type was more frequent among participants under inpatient SUD treatment. SZ+ patients had the highest amount of sleeping hours, lowest arousal and highest drowsiness followed by BD+ and MDD+, respectively. These observed differences suggest that treatment for patients with dual disorders could include chronobiological strategies to help them synchronize patterns with the day-light cycle, since morning-type is associated with better outcomes and recovery.

Demographic, psychological, chronobiological, and work-related predictors of sleep disturbances during the COVID-19 lockdown in Italy

The first COVID-19 contagion wave caused unprecedented restraining measures worldwide. In Italy, a period of generalized lockdown involving home confinement of the entire population was imposed for almost two months (9 March–3 May 2020). The present is the most extensive investigation aimed to unravel the demographic, psychological, chronobiological, and work-related predictors of sleep disturbances throughout the pandemic emergency. A total of 13,989 Italians completed a web-based survey during the confinement period (25 March–3 May). We collected demographic and lockdown-related work changes information, and we evaluated sleep quality, insomnia and depression symptoms, chronotype, perceived stress, and anxiety using validated questionnaires. The majority of the respondents reported a negative impact of confinement on their sleep and a delayed sleep phase. We highlighted an alarming prevalence of sleep disturbances during the lockdown. Main predictors of sleep disturbances identified by regression models were: female gender, advanced age, being a healthcare worker, living in southern Italy, confinement duration, and a higher level of depression, stress, and anxiety. The evening chronotype emerged as a vulnerability factor, while morning-type individuals showed a lower predisposition to sleep and psychological problems. Finally, working from home was associated with less severe sleep disturbances. Besides confirming the role of specific demographic and psychological factors in developing sleep disorders during the COVID-19 pandemic, we propose that circadian typologies could react differently to a particular period of reduced social jetlag. Moreover, our results suggest that working from home could play a protective role against the development of sleep disturbances during the current pandemic emergency.

The Eveningness Chronotype and Lower Adherence to the Mediterranean Diet Are Associated With Depressive Symptoms in Older Subjects With Metabolic Syndrome

Objectives Studies have shown the importance of depression as a risk factor for several diseases. Likewise, currently there is great interest on the role of chronotype in depressive disorders. Similarly, associations between diet and depression have been reported. However, very few studies have analyzed the combined effect of diet and chronotype on depression. Our aim was to investigated the joint influence of the morning/evening chronotype and adherence to the Mediterranean diet (MeDiet) on depressive symptoms in older subjects with metabolic syndrome. Methods We analyzed 465 PREDIMED Plus-Valencia study participants (aged 55–75). We assessed depressive symptoms by the Beck Depression Inventory (BDI). A higher score indicated more severe depressive symptoms. Adherence to the MedDiet was evaluated by the 17-item MeDiet score. Chronotype was assessed with the Morningness-Eveningness Questionnaire (MEQ). A higher total score indicated morningness. The 5 MEQ cut-offs were: definitely morning type, moderately morning type, intermediate type, moderately evening type, and definitely evening type. Multivariable models with interaction terms were fitted. Results Depressive symptons were statistically higher in women (P = 1.5 × 10–8) and in type 2 diabetes participants (P < 0.01). Adherence to the MeDiet was inversely associated with depression in the whole population (P < 0.001) and no significant heterogeneity by sex or by diabetes status was detected (P-interactions < 0.05). The morningness-eveningness mean score was inversely associated with depression, being the association statistically higher when we used the 5-categories for chronotypes. In a multivariable regression model adjusted for sex, diabetes, age, body mass index and physical activity, both adherence to the MedDiet (beta = –0.28; P = 0.010) and the chronotype (beta = –0.90; P = 0.047) remained statistically associated with the BDI score, showing additive effects. When we tested the interaction terms between chronotype and MedDiet adherence (P = 0.498) no significant heterogeneity was found. Conclusions The eveningness chronotype was associated with higher depressive symptoms, but a higher adherence to the MeDiet (inversely related with depression) may counteract the chronotype risk in an additive effect. Funding Sources CIBEROBN 06/03/035, PROMETEO 17/2017, P1 1B201354.

Biological clock vs Social clock conflict in Adolescents

Alteration of day and night is one of the essential circadian rhythms that build the phenomenon of sleep/wake in humans and other animals. Daily rhythms impact different individuals differently. Light exposure and an individual's circadian response are two aspects that create diversity in phenotype. These diverse phenotypes are called chronotypes. Chronotype varies over the life history stages. Chronotype is seen as morning type in children, evening type in adolescents, and again reverts back to the morning type in adults and old-aged individuals. It is observed that adolescents being evening types have bedtime later in comparison to children and adults. Adolescent physiology/ body clock does not allow them to sleep early and school routine/social clock does not let them sleep till late. Thus, their night phase is shrunk and sleep hours are reduced, which hinders their day-time functioning, including mental tasks such as cognition, learning and memory-based exercises, and physical tasks such as physical presence during field and athletic events. These days sleep debt is a critical health concern in the adolescent population. The current review focuses on the adolescent sleep-needs and various factors affecting their healthy sleep. This also encompasses the understanding of biological clocks, their misalignment, disrupters, causes and impact. The present study would be helpful in finding out the difference between the biological clock and social clock of the adolescent population, elaborates the need for sleep education and suggests a solution to this alarming problem of sleep debt in teens.

Circulating inflammatory markers may mediate the relationship between low carbohydrate diet and circadian rhythm in overweight and obese women

Background Low carbohydrate diet (LCD) can improve inflammation and obesity and also circadian rhythm disorders can lead to increased inflammation in obese individuals. The purpose of this study is to evaluate the association between adherence of LCD and circadian rhythm mediated by inflammatory markers including transforming growth factor-β (TGF-β), interleukin-1β (IL-1β) and Galectin-3 in overweight and obese women. Methods 304 women affected by overweight and obesity were enrolled. We evaluated LCD scores by Semi-quantitative food frequency questionnaire (FFQ) of 147 items. The morning-evening questionnaire (MEQ) was applied to evaluate the circadian rhythm. Biochemical parameters such as inflammatory markers and anthropometric components were assessed. Results There was a negative significant correlation between adherence of LCD and circadian rhythm status. In other words, as the LCD scores increased, the odds of circadian rhythm disturbance in intermediate group and morning type persons decreased compared to evening type. It was showed that, IL-1β and Galectin-3 in intermediate and morning type groups, destroyed the significance of this relationship and may be considered as mediating markers. Conclusion Adherence of LCD can improve the circadian rhythm by reducing levels of inflammatory markers and may be considered as a treatment for obesity.

Sleep/wake rhythm and its association with lifestyle, health-related quality of life and academic performance among Japanese nursing students: A cross-sectional study

Background: Young adults are likely to have activities and go to bed late at night due to their age-dependent delayed endogenous circadian clock. The purpose of the present study was to clarify sleep/wake rhythm and its association with lifestyle, health-related quality of life, and academic performance among nursing students.Methods: Self-reported questionnaires were distributed to undergraduate nursing students at six universities in Japan. Sleep/wake rhythm was assessed using the morningness-eveningness questionnaire. A quantitative design using the generalized linear mixed effect model was utilized to identify the factors related to the evening type among female nursing students (n=447). Results: About 18% of the participants were identified as the evening type. Evening type was associated with living alone, part-time job, and club activity. Sleep duration on weekdays was shorter, meal time duration was the shortest, and the percentages of students who skipped meals and those who gained body weight were higher in the evening type than in the morning type and intermediate type. Mental health-related quality of life was lower in the intermediate type and evening type than in the morning type, while there was no difference in physical health-related quality of life among these groups. The percentages of the nursing students who have experienced absence, tardiness, falling asleep during class, and/or interference with academic achievement were higher in the evening type than in other groups.Conclusions: The present study has important implications for nursing students’ biological characteristics and lifestyle, which are associated with their health-related quality of life and academic performance.

Chronotype, general health and quality of sleep in a population of Spanish nurses

ABSTRACT Objective The aim of this study was to investigate the association between chronotype, general health status and sleep quality in a sample of Spanish nurses. Method An observational study assessing morningness-eveningness predisposition, general health status and quality of sleep was conducted between January and April 2018. Univariate and multivariate analyses were performed. A linear regression model was carried out to determine the influence of the variables on the morningness-eveningness type. Results Morning-type was associated with aging (β = 0.249, p = 0.005), being married (β = 3.970, p = 0.033), and with a self-assessed low daily sleepiness (β = -0.311, p = 0.152). Good quality of sleep was moderately correlated with high values of general health (r = 0.337) and perceived quality of life (r = 0.426). Conclusion Anomalies of the circadian rhythm together with the features of shift workers may play an important role in predicting self-assessed general health status or the quality of sleep in nurses.