Impact Of Chronotype Research Articles

When Do Larks and Owls go the Extra Mile? The Impact of Chronotype on OCB via Time Extension Self-Efficacy

When Do Larks and Owls go the Extra Mile? The Impact of Chronotype on OCB via Time Extension Self-Efficacy

Impact of Sleep Duration, Quality, and Chronotype on Learning and Academic Performance: A Cross-Sectional Study Among First Year Medical Students of a Tertiary Care Institute.

Introduction The link between sleep and cognitive processes, such as memory and learning, continues to be one of the most intriguing and perplexing theories. Undergraduate medical students in their first year are particularly vulnerable to sleep disturbances. Academic achievement and learning have been linked to sleep patterns, which include not only the quantity and quality of sleep but also the timing of sleep in relation to the natural sleep onsets, or chronotypes. There have been conflicting reports on the outcomes of sleep and relatively fewer researches focused on the impact of chronotypes on learning and academic achievement among medical students. The current study thus sought to determine the chronotypes of medical students, evaluate the quantity and quality of sleep, and determine the impact of these factors on learning and academic performance. Methods The study was conducted in the Department of Physiology, All India Institute of Medical Sciences (AIIMS) Gorakhpur, India. Sleep health was assessed in 167 first-year medical students using the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), morningness-eveningness questionnaire (MEQ), and sleep log books. Learning and memory assessment was performed using Raven's progressive matrices test. Grade point average (GPA) was used to assess their academic performance. The relationship of sleep scores with GPA and RPM scores were obtained by linear regression analysis. One-way analysis of variance (ANOVA) and unpaired t-test were used to investigate other comparisons among categories of chronotypes and those of mean GPA. A p-value of <0.05 was considered as significant. Results The mean GPA and RPM scores obtained in the groups with PSQI ≥ 5 (2.67± 1.1, 49.51 ±6.24, respectively) and PSQI < 5 (3.15± 0.59, 54.73± 4.01, respectively) and those in the group with ESS ≥ 10 (2.72± 1.17, 50.97± 5.92, respectively) and ESS < 10 (3.15 ± 0.6, 54.18± 3.91, respectively)varied with statistically significant differences (p < 0.05). Statistically significant R-squared values for the relationship of PSQI and ESS scores with RPM and GPA scores were obtained. No correlation between academic grades and chronotype was found. Poor GPA scores were found to be associated with reduced mean sleep duration for one week before the exams. Conclusion Learning and academic performance are negatively impacted by poor sleep quality and daytime sleep dysfunction. No definite evidence for the association of sleep chronotypes with the learning and memory could be attained. Higher test performance is more closely linked to the average sleep length over a duration of time preceding the exams.

The impact of chronotype on VO2max in university students at two different times of the day

Background and Study Aim. To choose the ideal training or performance times, it is crucial to assess VO2 max performance across different time-of-day particular chronotypes. This study aimed to investigate the differences in VO2 max between the chronotype of university students during the morning and evening time of the day. Material and Methods. Fifty-two university students (26 morning type and 26 evening type) with mean age 23.05± 2.07 years, weight 66.71±4.31Kg and height of 170.90±5.18 cm and BMI of 22.75±1.91kg/m2 were recruited based on the results of the Horne-Ostberg Morningness- Eveningness Questionnaire (MEQs) participated in this Cross-over study. VO2 max was measured directly by gas collected using mouth tube breath to breath through the use of the gas analyzer the AD instrument (model-ML206) with an incremental graded maximal exercise test done on the treadmill. Results. The morning type group's VO2 max was significantly better in the morning hour than it was in the evening (p=.013), and when the VO2 max of the evening type group was measured in the morning and evening hours and compared, there was a statistically significant difference in favour of the evening hours (p=.004). Additionally, there is no discernible difference between the VO2 max of the morning type and the evening type group either in the morning hours or the evening hours, but trends indicate that the morning type group has a higher VO2max in the morning hour and the same is true for the evening type group in the evening hour. Conclusion. The findings of this study showed an interaction between chronotype and time of the day in VO2 max. For endurance training, trainers should consider the individual's chronotype and time of the day for exercise prescription.

Impact of Chronotype and Mediterranean Diet on the Risk of Liver Fibrosis in Patients with Non-Alcoholic Fatty Liver Disease.

Late chronotype, the individual's aptitude to perform daily activities late in the day, has been associated with low adherence to the Mediterranean diet (MedDiet) and metabolic syndrome. The aim of this work was to investigate the potential association of chronotype and adherence to the MedDiet with the liver fibrosis risk in patients with non-alcoholic fatty liver disease (NAFLD). Liver stiffness was assessed in 126 patients by FibroScan®530. Significant (F ≥ 2) and advanced (F ≥ 3) hepatic fibrosis were defined according to liver stiffness values ≥7.1 kPa and ≥8.8 kPa, respectively. Chronotype (MSFsc) was defined by the Munich Chronotype Questionnaire, and adherence to the MedDiet was defined by the Mediterranean diet score (MDS). Overall, the median age was 55 (46-63) years, and 57.9% of participants were male. The principal comorbidities were type-2 diabetes mellitus (T2DM) (26.1%), arterial hypertension (53.1%), dyslipidaemia (63.4%), obstructive sleep apnoea (5.5%) and depression (5.5%). Most subjects (65.0%) had intermediate + late chronotype and showed higher mid-sleep on workdays (p < 0.001) and on work-free days (p < 0.001) compared to those with early chronotype. In the logistic regression model, intermediate + late chronotype (p = 0.024), MDS (p = 0.019) and T2DM (p = 0.004) were found to be significantly and independently associated with the risk of both F ≥ 2 And F ≥ 3. We observed that the intermediate + late chronotype and low adherence to the MedDiet were associated with both significant and advanced liver fibrosis in patients with NAFLD.

School Attendance, Chronotype, and Day-of-the-Week Effect in Adolescent Male Basketball Players.

Adolescents' conflict between circadian rhythm and early school start time is more pronounced in evening chronotypes, who tend to reduce sleep duration during school days compensating during the free days by oversleeping (i.e., social jetlag). Cumulative weekly sleep debt may impair sport performance, which relies on physical and cognitive skills modulated by sleep. We hypothesized that chronotype predicts sport performance, and that it may interact with the day of the week. Moreover, given the role sleep plays in motor memory consolidation, we tested the hypothesis that school attendance, and the related chronic sleep deprivation, might be detrimental for participants in a training phase. Ninety-three adolescent male basketball players performed multiple free throw sessions (n = 7880) during both the school and holiday periods. Chronotype and its interaction with the day of the week significantly predicted shooting accuracy when attending school, but not on holidays. Evening types' performance gradually decreased from Monday to Friday. Participants with a more unstable performance (i.e., who did not complete the acquisition of the free throw motor scheme) worsened their accuracy when attending school. Our results suggest that the impact of chronotype and day of the week on sport performance is related to the presence of an externally imposed sleep/wake schedule and is consistent with evening types' increased likelihood of experiencing social jetlag. Possibly due to early school start time, attending school worsened the performance of participants in a training phase. Further investigations are required to assess whether reducing the mismatch between biological and social clocks might improve sport performance, along with other aspects of adolescents' life.

The Effect Of Chronotype On The Dose-Response To Field-Based Training In Elite Rugby League

Rugby League (RL) seasons are often congested, with matches often being played within the afternoon and evening hours. Despite this, training commonly occurs within the morning hours. To our knowledge, the impact of the start time of training and the impact of chronotype is yet to be examined in a RL context. PURPOSE: to examine the effect of chronotype and circadian variation on the dose-response to field-based training in elite RL. METHODS: 22 male RL players from a single National Rugby League club volunteered to participate in the study. Their chronotype was categorised by a newly validated index, the Athlete Specific Chronotype Index (ACTi). Training start time was categorised as morning (before midday), afternoon (12:00 to 18:00 h) or evening (after 18:00 h). Physical performance was recorded during 47 pre-season and 67 in-season main training sessions, using GPS units sampling at 10 Hz (Optimeye S5, Catapult Interventions, Scorsby, Australia). Performance metrics included relative distance covered (m·min-1), relative high speed running distance (HSR (m·min-1); > 14.4 km·h-1), PlayerLoad 2D (arbitrary units; AU) PlayerLoad slow (AU) and acceleration load (AU). Perceptual measures included self-reported wellness (sleep quality and readiness to train) and session ratings of perceived exhaustion (sRPE). RESULTS: 11 players were categorised as morning types, 10 as intermediate types and one as an evening type. There was no influence of chronotype on pre-training wellness measures (p = 0.35 - 0.75). Start time of main training sessions influenced readiness (p = 0.002) and sleep quality (p < 0.001) with a 0.20 AU increase in readiness and a 0.57 AU increase in sleep quality between 07:00 and 19:00 h. No influence of chronotype was found on the sRPE response to external load (p = 0.12 - 0.63). The start time of main training sessions affected the sRPE response to PlayerLoad slow (p = 0.004) and acceleration load (p = 0.01). Post-hoc analysis revealed a lower sRPE response to PlayerLoad slow and acceleration load within the evening training sessions compared to morning and afternoons. CONCLUSION: The majority of athletes were categorised as earlier chronotypes, however they showed improved wellness prior to evening sessions and reduced sRPE responses to accelerometer and locomotor based metrics within these sessions.

Impact Of Chronotype On Exercise Fuel Metabolism And Non-exercise Physical Activity

Impact Of Chronotype On Exercise Fuel Metabolism And Non-exercise Physical Activity

0318 Subjective Sleep and Cognition in Middle-aged and Older Adults: Chronotype and Sex as Moderators

Abstract Introduction Associations between sleep and cognition are well studied in aging populations. However, less is known regarding the moderating impact of chronotype (morningness vs. eveningness) and sex on these relationships. We aimed to determine the sex-specific moderating impact of subjective chronotype on the association between subjective sleep and subjective cognition in middle-aged and older adults. Methods Participants (N=260, 142 men/118 women) aged 50+ completed surveys measuring subjective sleep [Pittsburgh Sleep Quality Scale (PSQI)], chronotype [Morning-Evening Questionnaire (MEQ)], and everyday subjective cognition [Cognitive Failures Questionnaire (CFQ)]. Moderated regressions determined independent and interactive roles of subjective sleep (PSQI-total, sleep disturbances, sleep efficiency), chronotype (MEQ total), and sex on everyday subjective cognition (CFQ scores: total, memory, distractibility, and blunders). Analyses controlled for age, education, depressive/anxiety symptoms, and sleep medication use. Results Sex moderated the interactive associations of chronotype and PSQI-total on CFQ-total (p=.005) and CFQ-memory (p&amp;lt;.001). Specifically, higher PSQI-total was associated with higher CFQ-total (B=0.87, SE=0.38, p=.02) and CFQ-memory scores (B=0.33, SE=0.13, p=.009) in men with a tendency for eveningness. Sex also moderated the interactive associations of chronotype and PSQI-sleep disturbances on CFQ-memory (p=.04) and CFQ-blunders (p=.02). In men with a tendency for eveningness, greater PSQI-sleep disturbances were associated with worse CFQ-memory (B=2.65, SE=.84, p=.002) and CFQ-blunders scores (B=1.85, SE=0.83, p=.03). In women with a tendency for morningness, greater PSQI-sleep disturbances were associated with worse CFQ-memory (B=2.65, SE=.81, p= .001) and CFQ-blunders scores (B=2.37, SE=0.81, p=.004). Conclusion There are sex-specific patterns regarding the moderating impact of chronotype on associations between sleep and everyday cognition in middle aged and older adults. In men prone to eveningness, worse overall sleep quality and sleep disturbances may exacerbate negative perceptions of overall and memory specific cognitive function. However, in women prone to morningness, greater sleep disturbances may exacerbate negative perceptions of memory and task execution. Further investigating chronotype on objective sleep and cognition in prospective studies may help further explain underlying mechanisms of the impact of sleep on cognition, in addition to sex-specific sleep interventions to mitigate cognitive decline in aging populations. Support (If Any)

Adherence to the Mediterranean Diet and Its Association With Sleep Quality and Chronotype Among Youth: A Cross-Sectional Study.

BackgroundEvidence indicates that many university students have poor adherence to a healthy diet accompanied by unhealthy lifestyle behaviors. Chrono-nutrition is an emerging field of research that examines the pattern of optimum daily activity in relation to the human's dietary patterns, and their reflections of variable health indicators such as sleep quality. However, there is a scarcity of research that examines the relationship between adherence to the healthy eating pattern, like the Mediterranean diet (MD), with sleep quality and chronotype among university students.MethodsA cross-sectional study was conducted, and convenience sampling was used. Participants were assessed for adherence to the MD using the Mediterranean Diet Quality Index (KIDMED), for sleep quality using the Pittsburgh Sleep Quality Index (PSQI), and for chronotype using the Morningness-Eveningness questionnaire (MEQ).ResultsThe study included 503 university students, most of them (81.5%) were females. Only 15.1 and 16.9% reported morningness chronotype and good sleep quality, respectively. About half of the students showed medium and high adherence to the KIMED. In-depth analysis revealed that students with good adherence to the MD were more likely to have a good sleep quality (OR = 0.35; 95%CI: 0.21–0.59; P < 0.001) even after adjustment for age and sex (OR = 0.36; 95%CI: 0.21–0.62; P < 0.001). The regression analysis also showed that those with good adherence to the MD had a significant association with better subjective sleep quality, less sleep latency, sleep disturbance, and daytime dysfunction even after adjustment for age and sex. Those with morningness chronotype had about a six-fold higher chance to have good adherence to the MD (OR = 5.67; 95%CI: 2.86–11.26; P < 0.001, respectively).ConclusionsGood adherence to the healthy diet presented in the MD among university students is associated with morningness chronotype and with improved overall sleep quality and sleep components. Long-term, controlled intervention research works are warranted for more elaboration on the impact of chronotype and dietary habits on sleep quality and other important aspects such as mental health and academic achievement.

The impact of chronotype on circadian rest-activity rhythm and sleep characteristics across the week

ABSTRACT Circadian rhythms are maintained by a complex “system of systems” that continuously coordinates biological processes with each other and the environment. Although humans predominantly entrain to solar time, individual persons vary in their precise behavioral timing due to endogenous and exogenous factors. Endogenous differences in the timing of individual circadian rhythms relative to a common environmental cue are known as chronotypes, ranging from earlier than average (Morningness) to later than average (Eveningness). Furthermore, individual behavior is often constrained by social constructs such as the 7-day week, and the “sociogenic” impact our social calendar has on our behavioral rhythms is likely modified by chronotype. Our aim in this study was to identify and characterize differences in sleep and rest-activity rhythms (RAR) between weekends and weekdays and between-chronotypes. Male volunteers (n = 24, mean age = 23.46 y) were actigraphically monitored for 4 weeks to derive objective behavioral measures of sleep and RARs. Chronotype was assessed through self-report on the Morningness-Eveningness Questionnaire. Sleep characteristics were derived using Actiware; daily rest-activity rhythms were modeled using a basic 3-parameter cosinor function. We observed that both Eveningness and Morningness Chronotypes were more active and slept later on the weekends than on weekdays. Significant between-chronotype differences in sleep timing and duration were observed within individual days of the week, especially during transitions between weekends and the workweek. Moreover, chronotypes significantly varied in their weekly rhythms: e.g. Morningness Chronotypes generally shifted their sleep duration, timing and quality across work/rest transitions quicker than Eveningness Chronotypes. Although our results should be interpreted with caution due to the limitations of our cosinor model and a homogenous cohort, they reinforce a growing body of evidence that day of the week, chronotype and their interactions must be accounted for in observational studies of human behavior, especially when circadian rhythms are of interest.

Predictive role of socio-demographic and chronotype on health-related quality of life of cancer patients from southeastern India

ABSTRACT It is well known that cancer and its treatment produce marked impact on the health-related quality of life (HRQoL) of cancer patients. Research concerning impact of chronotype on HRQoL in cancer patients is almost not studied yet, but the interests are growing in several diseases. Present study was carried out to explore the impact of socio-demographics, chronotype and consumption of tobacco, alcohol and sleeping medicine on HRQoL of Indian oncology patients. Self-reported Quality-of-Life questionnaire (EORTC QLQ-C30), Hospital Anxiety and Depression Scale (HADS), and Morningness-Eveningness Questionnaire (MEQ) were administered to the cancer patients (N = 1000) in the native Hindi language. Results revealed that among the socio-demographic factors, only age exhibited significant negative association with physical, role and cognitive functioning and positive association with symptoms, namely fatigue and pain. Interestingly, chronotype was found to be positively associated with emotional functioning and negatively with nausea-vomiting, dyspnoea, diarrhoea and depression. Patients who consumed tobacco, alcohol or sleeping medicine exhibited lower functioning and higher symptoms. Further, treatment of cancer also produced effect on a few measures of HRQoL of patients. In conclusion, age, chronotype and consumption of tobacco, alcohol or sleeping medicine were found to be important determinants of HRQoL of the patients.

0283 Differential Impact of Chronotype on Positive and Negative Affect Following Sleep Restriction

Abstract Introduction Previous research indicates sleep deprivation significantly decreases positive affect, while negative affect is often unaffected (Reddy et al., 2017; Schwarz et al., 2019). However, it is unclear whether individual difference factors predict a differential emotional response to sleep loss. Though one study found chronotype predicts decreased positive affect following sleep loss in adolescents (Dagys et al., 2012), the effect of chronotype on emotional response to sleep loss in adults remains unknown. Methods The present study addressed this limitation by examining whether chronotype predicts changes in positive and negative affect following partial sleep restriction. Healthy sleeping adults (N=113; Insomnia Severity Index&amp;lt;8) completed the Morningness-Eveningness Questionnaire (Horne &amp; Ostberg, 1976) on day 1, and were instructed to sleep normally on night 1. On the evening of day 2, participants completed the Positive and Negative Affect Schedule (PANAS; MacKinnon et al., 1999) to sample baseline daily emotions. On night 2, sleep was restricted to 4-8am. On day 3, participants completed the PANAS post-sleep restriction. Compliance was verified with actigraphy (n=22 excluded for noncompliance), and response to the sleep restriction procedure was checked with the Stanford Sleepiness Scale (Hoddes, Dement, &amp; Zarcone, 1972; n=18 excluded for nonresponse). Results Results suggest a significant decrease in positive affect from pre-sleep restriction (M=15.63, SD=4.09) to post-sleep restriction (M=11.08, SD=3.93), t(71)=10.33, p&amp;lt;.01, and a trend decrease in negative affect from pre-sleep restriction (M=7.68, SD=3.62) to post-sleep restriction (M=6.90, SD=2.41), t(71)=1.60, p=07. Chronotype was significantly associated with post-sleep restriction negative affect, controlling for baseline negative affect (β=-.42, p&amp;lt;.01), such that eveningness was associated with increased negative affect following sleep restriction. In contrast, chronotype was unrelated to post-sleep restriction positive affect. Conclusion These findings indicate that evening types may be more likely to experience emotions implicated in anxiety-related disorders following sleep loss, such as fear and nervousness. Support This work was supported by the National Institute of Mental Health of the National Institutes of Health [F31MH113271] and a Graduate Student Summer Research Award from Vanderbilt University. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

The impact of chronotype on prosocial behavior.

IntroductionChronotype (morningness/eveningness) is associated with preference for the timing of many types of behavior, most notably sleep. Chronotype is also associated with differences in the timing of various physiologic events as well as aspects of personality. One aspect linked to personality, prosocial behavior, has not been studied before in the context of chronotype. There are many variables contributing to who, when, and why one human might help another and some of these factors appear fixed, while some change over time or with the environment. It was our intent to examine prosocial behavior in the context of chronotype and environment.MethodsRandomly selected adults (N = 100, ages 18–72) were approached in a public space and asked to participate in a study. If the participants consented (n = 81), they completed the reduced Morning-Eveningness Questionnaire and the Stanford Sleepiness Scale, then prosocial behavior was assessed.Results/ConclusionsWe found that people exhibited greater prosocial behavior when they were studied further from their preferred time of day. This did not appear to be associated with subjective sleepiness or other environmental variables, such as ambient illumination. This suggests the importance of appreciating the differentiation between the same individual’s prosocial behavior at different times of day. Future studies should aim at replicating this result in larger samples and across other measures of prosocial behavior.

Impact of chronotype on athletic performance: current perspectives

Impact of chronotype on athletic performance: current perspectives

Impact of chronotype and time perspective on the processing of scripts

Little is known about the impact of temporal orientation (chronotype; time perspective) on cognitive performance. This study adopted a psychophysiological approach to explore how chronotype (morningness–eveningness) and time perspective (present; future) influence time succession as another aspect of psychological time that is entailed within script knowledge. In a temporal judgment task, participants decided which of the two presented sub-events (e.g., get new batteries–set right time on alarm clock) comes earlier (or later) within a given script (e.g., changing batteries in an alarm clock). Behavioral and pupillary data suggest a differential impact of chronotype and time perspective on script knowledge and cognitive performance. The impact of time perspective on the processing of temporal information entailed in script knowledge appears linked to match or mismatch conditions between a strong focus on future outcomes associated with future time perspective and the task of identifying either the later (future-oriented) or the earlier (past-oriented) sub-event. Concerning the chronotype, evening types process items in which chronological time succession is violated (i.e., reversely presented items) more accurately than morning types. Indexed by pupillary data, the impact of chronotype may relate to more general cognitive abilities. The psychophysiological data derived in this study suggests that evening types typically outperform morning types in various measures such working memory capacity and verbal intelligence simply because they invest more cognitive resources than morning types.