Cross-sectional associations between 24-hour time-use composition, grey matter volume and cognitive function in healthy older adults.

BACKGROUND: Increasing physical activity (PA) is an effective strategy to slow reductions in cortical volume and maintain cognitive function in older adulthood. However, PA does not exist in isolation, but coexists with sleep and sedentary behaviour to make up the 24-hour day. We investigated how the balance of all three behaviours (24-hour time-use composition) is associated with grey matter volume in healthy older adults, and whether grey matter volume influences the relationship between 24-hour time-use composition and cognitive function. METHODS: This cross-sectional study included 378 older adults (65.6 ± 3.0 years old, 123 male) from the ACTIVate study across two Australian sites (Adelaide and Newcastle). Time-use composition was captured using 7-day accelerometry, and T1-weighted magnetic resonance imaging was used to measure grey matter volume both globally and across regions of interest (ROI: frontal lobe, temporal lobe, hippocampi, and lateral ventricles). Pairwise correlations were used to explore univariate associations between time-use variables, grey matter volumes and cognitive outcomes. Compositional data analysis linear regression models were used to quantify associations between ROI volumes and time-use composition, and explore potential associations between the interaction between ROI volumes and time-use composition with cognitive outcomes. RESULTS: After adjusting for covariates (age, sex, education), there were no significant associations between time-use composition and any volumetric outcomes. There were significant interactions between time-use composition and frontal lobe volume for long-term memory (p = 0.018) and executive function (p = 0.018), and between time-use composition and total grey matter volume for executive function (p = 0.028). Spending more time in moderate-vigorous PA was associated with better long-term memory scores, but only for those with smaller frontal lobe volume (below the sample mean). Conversely, spending more time in sleep and less time in sedentary behaviour was associated with better executive function in those with smaller total grey matter volume. CONCLUSIONS: Although 24-hour time use was not associated with total or regional grey matter independently, total grey matter and frontal lobe grey matter volume moderated the relationship between time-use composition and several cognitive outcomes. Future studies should investigate these relationships longitudinally to assess whether changes in time-use composition correspond to changes in grey matter volume and cognition.

Long-term influence of sleep/wake history on the dynamic neurobehavioural response to sustained sleep restriction.

Chronic sleep restriction, common in today's 24/7 society, causes cumulative neurobehavioural impairment, but the dynamics of the build-up and dissipation of this impairment have not been fully elucidated. We addressed this knowledge gap in a laboratory study involving two, 5-day periods of sleep restriction to 4 hr per day, separated by a 1-day dose-response intervention sleep opportunity. We measured sleep physiological and waking neurobehavioural responses in 70 healthy adults, each randomized to one of seven dose-response intervention sleep doses ranging from 0 to 12 hr, or a non-sleep-restricted control group. As anticipated, sleep physiological markers showed homeostatic dynamics throughout the study, and waking neurobehavioural impairment accumulated across the two sleep restriction periods. Unexpectedly, there was only a slight and short-lived effect of the 1-day dose-response intervention sleep opportunity. Whether the dose-response intervention sleep opportunity involved extension, further restriction or total deprivation of sleep, neurobehavioural functioning during the subsequent second sleep restriction period was dominated by prior sleep-wake history. Our findings revealed a profound and enduring influence of long-term sleep-wake history as a fundamental aspect of the dynamic regulation of the neurobehavioural response to sleep loss.

Allergic disease, sleep problems, and psychological distress in children recruited from the general community.

BACKGROUND: It is not clear which allergic disease is most strongly related to which sleep problem and whether sleep problems may mediate the association between allergic disease and psychological distress. There is also a need for more community-based studies using nonreferred samples. OBJECTIVE: To evaluate the association between individual allergic diseases and sleep problems and test whether the association between allergic disease and psychological distress is mediated through sleep problems. METHODS: Parents of 1449 Australian children aged 6 to 10 years recruited from the general community, completed measures of sleep problems (Pediatric Sleep Survey Instrument), psychological distress (Strengths and Difficulties Questionnaire), and frequency of allergic diseases. RESULTS: Sleep and psychological distress scores were in the reference range. After controlling for coexisting allergic diseases, allergic rhinitis was associated with sleep routine problems, morning tiredness, night arousals, sleep disordered breathing and restless sleep; asthma with sleep routine problems, sleep disordered breathing and restless sleep; and eczema with restless sleep. Path analyses revealed that sleep problems mediated the association between asthma and allergic rhinitis but not eczema with psychological distress. CONCLUSION: In this nonreferred community sample, the frequency of sleep problems and psychological distress was lower than that typically reported in children referred to specialized centers. However, allergic rhinitis was associated with a broad range of sleep problems and to a lesser extent in children with asthma and least in children with eczema. Path analysis revealed that the association between allergic disease and psychological distress was mediated through sleep problems, highlighting the importance of assessing sleep health in children with allergic disease.

A scoping review of chronotype and temporal patterns of eating of adults: tools used, findings, and future directions.

Circadian rhythms, metabolic processes and dietary intake are inextricably linked. Timing of food intake is a modifiable temporal cue for the circadian system and may be influenced by numerous factors, including individual chronotype - an indicator of an individual's circadian rhythm in relation to the light-dark cycle. This scoping review examines temporal patterns of eating across chronotypes and assesses tools that have been used to collect data on temporal patterns of eating and chronotype. A systematic search identified thirty-six studies in which aspects of temporal patterns of eating, including meal timings; meal skipping; energy distribution across the day; meal frequency; time interval between meals, or meals and wake/sleep times; midpoint of food/energy intake; meal regularity; and duration of eating window, were presented in relation to chronotype. Findings indicate that, compared with morning chronotypes, evening chronotypes tend to skip meals more frequently, have later mealtimes, and distribute greater energy intake towards later times of the day. More studies should explore the difference in meal regularity and duration of eating window amongst chronotypes. Currently, tools used in collecting data on chronotype and temporal patterns of eating are varied, limiting the direct comparison of findings between studies. Development of a standardised assessment tool will allow future studies to confidently compare findings to inform the development and assessment of guidelines that provide recommendations on temporal patterns of eating for optimal health.

Giving sleep position advice in pregnancy: Will we make women anxious?

BACKGROUND: There is now robust evidence that when women settle to sleep on their back in late pregnancy (>28 weeks) they are at increased risk of stillbirth. Therefore, there are several stillbirth prevention programs worldwide that have begun advising pregnant women to adopt a side position when settling to sleep in late pregnancy. However, some hold concerns that giving women information about sleep position and stillbirth risk may make them anxious. AIM: This study aimed to determine what influences how 'safe sleep' messages are perceived by pregnant women and if there is anxiety associated with receiving this message. MATERIALS AND METHODS: An online survey of 537 Australian women (n = 97 were 'currently pregnant'). The survey examined participant's views regarding sleep position messages, type of information source as well as participant characteristics such as general anxiety and their fetal health locus of control (FHLC). RESULTS: Our findings suggest that the FHLC may influence how health messaging regarding sleep in pregnancy is perceived and acted upon. We have also shown a subset of pregnant women may feel anxiety associated with the sleep position in pregnancy message. This may not be related to history of anxiety, but rather to their higher 'internal' FHLC, ie those who reflect a greater sense of personal agency over fetal health. CONCLUSIONS: Our findings suggest most women will perceive information about settling into sleep position as informative rather than anxiety provoking. Therefore, maternity care providers should not be overly concerned about provoking anxiety when providing this information.

Effectiveness of biodiversity-conservation marketing.

Conservation marketing holds potential as a means to engage audiences with biodiversity conservation and help to address the human dimensions of biodiversity loss. Empirical evaluations of conservation marketing indicatives are growing, so we reviewed the literature on this research to inform future directions in the field. We used a systematic search strategy to identify studies that evaluated the effects of conservation marketing interventions (techniques and campaigns) on psychosocial outcomes, categorized as cognitive, affective, or behavioral. Six academic databases (Business Source Complete, Communication & Mass Media Complete, Greenfile, Proquest, Scopus, and Web of Science Core Collections), 3 gray-literature databases (BASE, Zenodo, and Google Scholar), and 2 websites (Rare and WildAid) were searched. Articles were subjected to critical appraisal to assess their methodological quality, and data were extracted from each article and analyzed using narrative synthesis. Altogether 28 studies from 26 articles were included in the review. Twenty-five studies were conducted from 2014 through 2016. Methodological quality of most studies was weak (n = 16, 57%) (moderate quality n = 8, 29%; high quality n = 4, 14%). The proportion of studies that evaluated a conservation-marketing technique (e.g., variants of texts, images, or videos) versus a campaign (e.g., community-based campaigns targeting locally relevant issues, such as unsustainable palm oil agriculture, light pollution, or wood fuel fire use) was relatively balanced. Although many studies reported statistically significant results in the intended direction, the utility of findings was limited by persistent methodological limitations, such as a lack of a comparator group, use of non-validated assessment tools, and a focus on self-reported data and subjective outcomes. Conservation marketing is clearly a nascent field of scientific enquiry that warrants further, high-quality research investigations.

Efectividad de la Mercadotecnia de la Conservación de la Biodiversidad Resumen La mercadotecnia de la conservación tiene potencial como un medio para involucrar a audiencias en la conservación y ayuda a atender la dimensión humana de la pérdida de la biodiversidad. Ha habido un incremento de las evaluaciones empíricas de indicadores de la mercadotecnia de la conservación, por lo que revisamos la literatura sobre esta línea de investigación para dar información a trabajos futuros en este campo. Utilizamos una estrategia de búsqueda sistemática para identificar, evaluar críticamente y sintetizar los resultados de estudios que evaluaron los efectos de las intervenciones de la mercadotecnia de la conservación (técnicas y campañas) sobre las consecuencias psicosociales y relacionadas con el involucramiento, categorizadas como cognitivas, afectivas o conductuales. Realizamos búsquedas en seis bases de datos académicas ((Business Source Complete, Communication & Mass Media Complete, Greenfile, Proquest, Scopus, y Web of Science Core Collections), tres bases de datos de literatura gris (BASE, Zenodo, y Google Scholar) y dos sitios web (Rare y WildAid). Los artículos fueron sujetos a una evaluación crítica para determinar su calidad metodológica, y los datos de cada artículo fueron extraídos y analizados por medio de síntesis narrativa. En total se incluyeron 28 estudios de 26 artículos en la revisión. Veinticinco estudios se llevaron a cabo de 2014 a 2016. La calidad metodológica de la mayoría de los estudios fue baja (n = 16, 57%) (calidad moderada n = 8, 29%; calidad alta n = 4, 14%). La proporción de estudios que evaluaron una técnica de mercadotecnia de la conservación (e. g., variaciones de textos, imágenes o videos) versus una campaña (e. g., campañas comunitarias enfocadas a temas relevantes localmente, como el cultivo no sustentable de palma de aceite, la contaminación lumínica y el uso de madera como combustible) fue relativamente equitativa. Aunque muchos estudios reportaron resultados significativos estadísticamente, la utilidad de los resultados fue limitada por las limitaciones metodológicas persistentes, como la falta de un grupo para comparar, el uso de herramientas de evaluación no validadas y el enfoque en datos auto reportados y resultados subjetivos. La mercadotecnia de la conservación es un campo de conocimiento claramente incipiente que garantiza investigaciones futuras de alta calidad.

Proceed with caution: using verbal protocol analysis to measure situation awareness.

Verbal protocol analysis (VPA) is often used to elicit information about the cognitive processes of operators as it provides rich data and can be used in naturalistic settings. Recently VPA has been used to investigate the acquisition and maintenance of situation awareness (SA), and to make comparisons between groups despite a lack of research regarding the efficacy of using VPA for this purpose. This train simulator experiment investigated whether VPA can effectively measure SA. Novice and expert participants were recorded on an audio device while talking aloud throughout the trials and their verbalisations were transcribed verbatim. A coding scheme developed from the transcripts was used to code the verbalisations. Results did not support the use of VPA as a measure of SA but did show that VPA detected differences in SA errors. Potential reasons for the conflicting findings between this experiment and those conducted by other researchers are discussed. Practitioner summary: This paper examined the validity of verbal protocol analysis (VPA) as a situation awareness (SA) measure. A repeated measures experiment was conducted using a train simulator. Normal VPA did not detect changes in SA but a measure of errors did. Caution should be used when using VPA to measure SA. Abbreviations: LETSSA: low-event task subjective situation awareness technique; SA: situation awareness; SAGAT: situation awareness global assessment technique; TPD: train performance display; VPA: verbal protocol analysis.

Associations between self-reported sleep measures and dietary behaviours in a large sample of Australian school students (n = 28,010).

This study examined the associations between self-reported sleep timing and quality, and the frequency of breakfast and junk food consumption in 28,010 Australian school students (mean ± SD age = 13.3 ± 1.2 years, 51% male). After controlling for age, sex and socioeconomic status, regression analyses revealed that the odds of missing breakfast were significantly higher in children who reported poor sleep or later bedtimes, while the odds of junk food consumption were significantly higher in children reporting later weeknight bedtimes (p < 0.001). These findings suggest that sleep timing and quality influence the dietary choices of adolescents.

The impact of caffeine consumption during 50 hr of extended wakefulness on glucose metabolism, self-reported hunger and mood state.

Caffeine is known for its capacity to mitigate performance decrements. The metabolic side-effects are less well understood. This study examined the impact of cumulative caffeine doses on glucose metabolism, self-reported hunger and mood state during 50 hr of wakefulness. In a double-blind laboratory study, participants were assigned to caffeine (n = 9, 6M, age 21.3 ± 2.1 years; body mass index 21.9 ± 1.6 kg/m2 ) or placebo conditions (n = 8, 4M, age 23.0 ± 2.8 years; body mass index 21.8 ± 1.6 kg/m2 ). Following a baseline sleep (22:00 hours-08:00 hours), participants commenced 50 hr of sleep deprivation. Meal timing and composition were controlled throughout the study. Caffeine (200 mg) or placebo gum was chewed for 5 min at 01:00 hours, 03:00 hours, 05:00 hours and 07:00 hours during each night of sleep deprivation. Continual glucose monitors captured interstitial glucose 2 hr post-breakfast, at 5-min intervals. Hunger and mood state were assessed at 10:00 hours, 16:30 hours, 22:30 hours and 04:30 hours. Caffeine did not affect glucose area under the curve (p = 0.680); however, glucose response to breakfast significantly increased after 2 nights of extended wakefulness compared with baseline (p = 0.001). There was a significant main effect of day, with increased tiredness (p < 0.001), mental exhaustion (p < 0.001), irritability (p = 0.002) and stress (p < 0.001) on the second day of extended wake compared with day 1. Caffeine attenuated the rise in tiredness (p < 0.001), mental exhaustion (p = 0.044) and irritability (p = 0.018) on day 1 but not day 2. Self-reported hunger was not affected by sleep deprivation or caffeine. These data confirm the effectiveness of caffeine in improving performance under conditions of sleep deprivation by reducing feelings of tiredness, mental exhaustion and irritability without exacerbating glucose metabolism and feelings of hunger.

An experimental study of adolescent sleep restriction during a simulated school week: changes in phase, sleep staging, performance and sleepiness.

This laboratory study investigated the impact of restricted sleep during a simulated school week on circadian phase, sleep stages and daytime functioning. Changes were examined across and within days and during a simulated weekend recovery. Participants were 12 healthy secondary school students (six male) aged 15-17 years [mean = 16.1 years, standard deviation (SD) = 0.9]. After 2 nights with 10 h (21:30-07:30 hours), time in bed was restricted to 5 h for 5 nights (02:30-07:30 hours), then returned to 10 h time in bed for 2 nights (21:30-07:30 hours). Saliva was collected in dim light on the first and last sleep restriction nights to measure melatonin onset phase. Sleep was recorded polysomnographically, and the Psychomotor Vigilance Task (PVT) and Karolinska Sleepiness Scale were undertaken 3-hourly while awake. Average phase delay measured by melatonin was 3 h (SD = 50 min). Compared to baseline, sleep during the restriction period contained a smaller percentage of Stages 1 and 2 and rapid eye movement (REM) and a greater percentage of Stage 4. PVT lapses increased significantly during sleep restriction and did not return to baseline levels during recovery. Subjective sleepiness showed a similar pattern during restriction, but returned to baseline levels during recovery. Results suggest that sustained attention in adolescents is affected negatively by sleep restriction, particularly in the early morning, and that a weekend of recovery sleep is insufficient to restore performance. The discrepancy between sleepiness ratings and performance may indicate a lack of perception of this residual impairment.

Evaluating the conservation impact of an innovative zoo-based educational campaign: 'Don't Palm Us Off' for orang-utan conservation.

With significant biodiversity loss occurring presently, increased emphasis is being placed upon the capacity of zoos to contribute to species conservation. This paper evaluates an innovative conservation education campaign 'Don't Palm Us Off' implemented at Melbourne Zoo, Australia. This sought to address a lack of public awareness regarding palm oil (the product most threatening the survival of the orang-utan) and to create public support for mandatory labeling of palm oil on food products, allowing for informed consumer purchasing. Communication tools utilized included an educational video presentation played on-site, as well as You Tube video, celebrity ambassadors, and social media. Evaluation took place across four time-points: baseline, mid-point, conclusion (12 months), and follow-up. Zoo visitors (N = 403) were randomly selected whilst visiting the orang-utan exhibit, completing a questionnaire regarding knowledge about orangutans, attitudes toward orangutans, support for palm oil labeling, previous conservation behavior, and intentions for future behavior. Results revealed significant increases in palm oil awareness; attitudes toward orangutans; support for palm oil labeling; and indicating labeling would influence purchasing behavior, at all times relative to baseline (P < 0.01). There were also significant increases in self-reported conservation behavior at the end of the campaign and follow-up (P < 0.05). In excess of 160,000 people additionally signed an associated petition for mandatory palm oil labeling. Overall the findings support the efficacy of this multi-faceted initiative; highlighting the importance of continued innovation in zoo-based conservation education and practice (including the integration of emerging technologies with traditional on-site education) to maximize contributions to species conservation.

Construct validity and test-retest reliability of a chrononutrition questionnaire for shift work and non-shift work populations.

The irregular eating patterns of both shift workers and evening chronotypes adversely affect cardiometabolic health. A tool that conveniently captures temporal patterns of eating alongside an indicator of circadian rhythm such as chronotype will enable researchers to explore relationships with diverse health outcome measures. We aimed to investigate the test-retest reliability and convergent validity of a Chrononutrition Questionnaire (CNQ) that captures temporal patterns of eating and chronotype in the general population (non-shift workers, university students, retirees, unemployed individuals) and shift work population. Participants attended two face-to-face/virtual sessions and completed the CNQ and food/sleep/work diaries. Outcomes included subjective chronotype, wake/sleep/mid-sleep time, sleep duration, meal/snack regularity, meal/snack/total frequency, times of first/last/largest eating occasions (EO), main meal (MM) 1/2/3, and duration of eating window (DEW). 116 participants enrolled (44.5 ± 16.5 years, BMI: 27.3 ± 5.8 kg/m2, 73% female, 52% general population); 105 completed the study. Reliability was acceptable for chronotype, sleep, and all temporal eating patterns except on night shifts. Convergent validity was good for chronotype and sleep except for certain shift/shift-free days. Generally, meal/snack regularity and frequency, and times of first/last EO showed good validity for the general population but not shift workers. Validity was good for DEW (except work-free days and afternoon shifts) and times of MM 1/2/3 (except afternoon and night shifts), while time of largest EO had poor validity. The CNQ has good test-retest reliability and acceptable convergent validity for the general and shift work population, although it will benefit from further validation, especially regarding regularity, frequency, and times of first and last eating occasions across more days amongst a larger sample size of shift workers. Use of the CNQ by researchers will expand our current understanding of chrononutrition as relationships between timing of food intake and the multitude of health outcomes are examined.

A circadian-informed lighting intervention accelerates circadian adjustment to a night work schedule in a submarine lighting environment.

STUDY OBJECTIVE: Night work has detrimental impacts on sleep and performance, primarily due to misalignment between sleep-wake schedules and underlying circadian rhythms. This study tested whether circadian-informed lighting accelerated circadian phase delay, and thus adjustment to night work, compared to blue-depleted standard lighting under simulated submariner work conditions. METHODS: Nineteen healthy sleepers (12 males; mean±SD aged 29 ±10 y) participated in two separate 8-day visits approximately one month apart to receive, in random order, circadian-informed lighting (blue-enriched and dim, blue-depleted lighting at specific times) and standard lighting (dim, blue-depleted lighting). After an adaptation night (day 1), salivary dim light melatonin onset (DLMO) assessment was undertaken from 18:00-02:00 on days 2-3. During days 3-7, participants completed simulated night work from 00:00-08:00 and a sleep period from 10:00-19:00. Post-condition DLMO assessment occurred from 21:00-13:00 on days 7-8. Ingestible capsules continuously sampled temperature to estimate daily core body temperature minimum (Tmin) time. Tmin and DLMO circadian delays were compared between conditions using mixed effects models. RESULTS: There were significant condition-by-day interactions in Tmin and DLMO delays (both p<0.001). After four simulated night shifts, circadian-informed lighting produced a mean [95%CI] 4.3 [3.3 to 5.4] h greater delay in Tmin timing and a 4.2 [3 to 5.6] h greater delay in DLMO timing compared to standard lighting. CONCLUSIONS: Circadian-informed lighting accelerates adjustment to shiftwork in a simulated submariner work environment. Circadian lighting interventions warrant consideration in any dimly lit and blue-depleted work environments where circadian adjustment is relevant to help enhance human performance, safety, and health.

Circadian-informed lighting improves vigilance, sleep, and subjective sleepiness during simulated night shift work.

STUDY OBJECTIVES: Shiftwork is associated with cognitive impairment and reduced sleep time and quality, largely due to circadian misalignment. This study tested if circadian-informed lighting could improve cognitive performance and sleep during simulated night shifts versus dim control lighting. METHODS: Nineteen healthy participants (Mean±SD 29±10 years, 12 males, 7 females) were recruited to a laboratory study consisting of two counterbalanced 8-day lighting conditions (order randomized) 1-month apart: 1) control lighting condition- dim, blue-depleted and 2) circadian-informed lighting condition- blue-enriched and blue-depleted where appropriate. Participants underwent an adaptation night (22:00h - 07:00h), then four nights of simulated nightwork (cognitive testing battery of nine tasks, 00:00h - 08:00h) and sleep during the day (10:00h - 19:00h). Psychomotor vigilance task (PVT) lapses, Karolinska Sleepiness Scale (KSS) scores, and polysomnography-derived sleep outcomes were compared between conditions and across days using mixed models. RESULTS: Significant condition-by-day-by-time of task interaction effects were found for PVT lapses, median reaction time, and reaction speed, with ~50% fewer lapses by the end of simulated shiftwork with circadian-informed lighting versus control (mean±SD 7.4±5.0 vs. 15.6±6.1). KSS was lower around the nightshift midpoints on days 6 and 7 with circadian versus control lighting. Participants slept 52 minutes longer [95% CIs: 27.5, 76.5 mins] by Day 7 with circadian-informed versus control lighting, p<0.001. Effects were inconsistent on other performance tasks. CONCLUSIONS: Circadian-informed lighting improved sleep, sleepiness, and vigilance compared to control lighting. These findings support the potential for lighting interventions to improve sleep and vigilance in night shift workers chronically exposed to dim lighting.

Evaluation of the "Shifting Weight using Intermittent Fasting in night-shift workers" weight loss interventions: a mixed-methods protocol.

Introduction: Shift workers are at a greater risk for obesity-related conditions. The impacts of working at night presents a challenge for designing effective dietary weight-loss interventions for this population group. The Shifting Weight using Intermittent Fasting in night-shift workers (SWIFt) study is a world-first, randomized controlled trial that compares three weight-loss interventions. While the trial will evaluate the effectiveness of weight-loss outcomes, this mixed-methods evaluation aims to explore for who weight-loss outcomes are achieved and what factors (intervention features, individual, social, organisational and wider environmental) contribute to this. Methods: A convergent, mixed-methods evaluation design was chosen where quantitative and qualitative data collection occurs concurrently, analyzed separately, and converged in a final synthesis. Quantitative measures include participant engagement assessed via: dietary consult attendance, fulfillment of dietary goals, dietary energy intake, adherence to self-monitoring, and rates for participant drop-out; analyzed for frequency and proportions. Regression models will determine associations between engagement measures, participant characteristics (sex, age, ethnicity, occupation, shift type, night-shifts per week, years in night shift), intervention group, and weight change. Qualitative measures include semi-structured interviews with participants at baseline, 24-weeks, and 18-months, and fortnightly audio-diaries during the 24-week intervention. Interviews/diaries will be transcribed verbatim and analyzed using five-step thematic framework analysis in NVivo. Results from the quantitative and qualitative data will be integrated via table and narrative form to interrogate the validity of conclusions. Discussion: The SWIFt study is a world-first trial that compares the effectiveness of three weight-loss interventions for night shift workers. This mixed-methods evaluation aims to further explore the effectiveness of the interventions. The evaluation will determine for who the SWIFt interventions work best for, what intervention features are important, and what external factors need to be addressed to strengthen an approach. The findings will be useful for tailoring future scalability of dietary weight-loss interventions for night-shift workers.Clinical trial registration: This evaluation is based on the SWIFt trial registered with the Australian New Zealand Clinical Trials Registry [ACTRN 12619001035112].

"Mars Bar and a Tin of Red Bull Kept Me and My Patients Alive": Exploring Barriers to Healthy Eating through Facebook Comments of Shiftworkers.

The negative impact of an unhealthy diet on the shiftworker population has been well-documented. However, little evidence exists on the underlying reasons for unhealthy eating behaviours and the existing barriers to healthy eating withinshiftwork environments. This qualitative study investigated the dietary behaviours reported by shiftworkers through Facebook comments. Comments were collected if they were on public shiftworker-relevant posts pertaining to dietary news or dietary information on Facebook and were posted by self-identified shiftworkers, relatives of shiftworkers, or partners of shiftworkers. A thematic analysis of the 144 comments collected generated four categories that can be used to understand the motivations for eating behaviour on-shift: what shiftworkers eat, where food is sourced from, when food is eaten, and why certain foods are chosen. Results reveal motivations, attitudes, and both internal and external barriers to healthy eating behaviours, as well as similarities and differences across shiftwork industries. Recommendations for future research include further explorations on the link between scheduled eating (e.g., time-restricted eating) and shiftwork, the impact of a rotating shift arrangements on dietary health behaviours, and the impact of interpersonal relationships on shiftworker dietary choices. Understanding these motivations will inform strategies to promote healthy eating and help understand barriers for shiftworkers.

Corrigendum: Twenty-four-hour time-use composition and cognitive function in older adults: cross-sectional findings of the ACTIVate study.

[This corrects the article DOI: 10.3389/fnhum.2022.1051793.].

Work schedule and seasonal influences on sleep and fatigue in helicopter and fixed-wing aircraft operations in extreme environments.

Sleep and fatigue were investigated in aviation search and rescue, firefighting, emergency medical services and offshore transfer operations in 210 participants, for 21 days each, across 17 datasets in seven countries. Sleep data were collected using wrist-worn actigraphs and sleep diaries. Sustained attention was assessed using a 5-min Psychomotor Vigilance Task (PVT). Duty information was provided from corporate IT systems. Despite the number of 24 h operations, most work occurred during daytime hours, and most sleep occurred at night. There were seasonal changes in work and sleep patterns, with naps used to augment total sleep time. The proportion of sleep occurring during duty varied from zero to 30%. Differences in PVT response times were trivial to small. Legislation that defines flight, duty time and minimum rest limits assume that sleep is not obtained during duty periods, apart from some napping under Fatigue Risk Management Systems (FRMS). However, especially in cases where the aviation service requires waiting for tasks (e.g. search and rescue, emergency medical response), this assumption may not always hold. FRMS should accommodate different modes of working that safely facilitate sleep during duty time where appropriate.

A survey of train driver schedules, sleep, wellbeing, and driving performance in Australia and New Zealand.

Train drivers work long hours on 24 h schedules and many factors impact their fatigue risk at work, creating a clear imperative for good rostering practice. Adopting a systems approach, this study investigated the relationship between multiple interrelated factors (train drivers' schedule, sleep, wellbeing, and fatigue) and the perceived influence of these factors on train driving performance and safety using an online survey distributed in Australia and New Zealand. In addition to demographics and work schedule, passenger and freight train drivers (n = 751) answered questions about: (1) Sleep duration; (2) wellbeing, including physical and mental health, the extent to which shiftwork causes sleep, social, domestic, and work problems, and (3) the extent to which ten fatigue, health and wellbeing factors in the work and home environment negatively impact their driving performance. The key factor that emerged from analyses, with the largest and most consistent negative effects (and controlling for other factors) was schedule irregularity. Approved rosters were ranked as having the most important impact on day-to-day driving performance, followed by physical and mental health, and outside work factors. Results also suggested that schedule irregularity may amplify the negative impacts of the roster, impaired physical and mental health, and outside work factors on driving performance. As shift variability and schedule irregularity are often poorly represented in existing industry guidance, these results provide evidence for increased reflection on current fatigue management guidelines for train drivers and suggest a need for greater focus on schedule irregularity through the lens of a systems approach.