The Discrepancy between Knowledge of Sleep Recommendations and the Actual Sleep Behaviour of Australian Adults

Calibrated to drive: Measuring self-assessed driving ability and perceived workload after prolonged sitting and sleep restriction

Self-assessed driving ability may differ from actual driving performance, leading to poor calibration (i.e., differences between self-assessed driving ability and actual performance), increased risk of accidents and unsafe driving behaviour. Factors such as sleep restriction and sedentary behaviour can impact driver workload, which influences driver calibration. This study aims to investigate how sleep restriction and prolonged sitting impact driver workload and driver calibration to identify strategies that can lead to safer and better calibrated drivers. Participants (n = 84, mean age = 23.5 ± 4.8, 49 % female) undertook a 7-day laboratory study and were randomly allocated to a condition: sitting 9-h sleep opportunity (Sit9), breaking up sitting 9-h sleep opportunity (Break9), sitting 5-h sleep opportunity (Sit5) and breaking up sitting 5-h sleep opportunity (Break5). Break9 and Break5 conditions completed 3-min of light-intensity walking on a treadmill every 30 min between 09:00-17:00 h, while participants in Sit9 and Sit5 conditions remained seated. Each participant completed a 20-min simulated commute in the morning and afternoon each day and completed subjective assessments of driving ability and perceived workload before and after each commute. Objective driving performance was assessed using a driving simulator measuring speed and lane performance metrics. Driver calibration was analysed using a single component and 3-component Brier Score. Correlational matrices were conducted as an exploratory analysis to understand the strength and direction of the relationship between subjective and objective driving outcomes. Analyses revealed participants in Sit9 and Break9 were significantly better calibrated for lane variability, lane position and safe zone-lane parameters at both time points (p < 0.0001) compared to Sit5 and Break5. Break5 participants were better calibrated for safe zone-speed and combined safe zone parameters (p < 0.0001) and speed variability at both time points (p = 0.005) compared to all other conditions. Analyses revealed lower perceived workload scores at both time points for Sit9 and Break9 participants compared to Sit5 and Break5 (p = <0.001). Breaking up sitting during the day may reduce calibration errors compared to sitting during the day for speed keeping parameters. Future studies should investigate if different physical activity frequency and intensity can reduce calibration errors, and better align a driver's self-assessment with their actual performance.

'It's satisfying but destructive': A qualitative study on the experience of bedtime procrastination in new career starters

BACKGROUND

Bedtime procrastination, the volitional delay of going to bed without any external circumstances causing the delay, is linked to multiple indicators of inadequate sleep. Intervening to reduce bedtime procrastination may be an important avenue to improve sleep outcomes, yet the phenomenon remains poorly understood in populations at risk for bedtime procrastination. New career starters, those who have graduated from tertiary education and started a new full-time job within the past 12 months, may be susceptible to problematic bedtime procrastination and are at an opportune time for a 'fresh start' to change behaviour.

AIMS

The objectives of this study were to understand how bedtime procrastination is experienced and perceived by new career starters, to identify the enablers and barriers to behaviour change in new career starters and to explore themes for future interventions.

MATERIALS & METHODS

Data were collected through in-depth semi-structured interviews with 28 participants.

RESULTS

Inductive thematic analysis was used to find seven themes: (1) negative feelings before and during bedtime procrastination; (2) wanting to versus knowing I shouldn't; (3) difficulty falling asleep; (4) influence of automatic processes; (5) consequences of bedtime procrastination; (6) lack of self-control and (7) technology captures late-night attention. Participants emphasised the need for me-time, self-negotiation to continue procrastinating and knowledge of the value of sleep.

DISCUSSION & CONCLUSION

Findings suggest that bedtime procrastination involves both reflective and automatic cognitive processes. Future interventions would benefit from a dual-process approach, using cognitive and behavioural techniques to reduce bedtime procrastination.

Symptoms of sleep problems and adherence to dietary guidelines in older women: evidence from the Australian Longitudinal Study on Women's Health

OBJECTIVE

This study examined adherence to dietary guidelines and symptoms of sleep problems (e.g. taking a long time to fall sleep or waking up early) and their associations in a sample of older Australian women (68-73 years of age).

DESIGN

This was a population-based cross-sectional study. Adherence to the dietary guidelines was measured using a validated FFQ and reported as a diet quality score. Symptoms of sleep problems were measured using five questions and a total score was derived. Multivariate linear regression was used to investigate the association between these outcomes, adjusted for the potential confounding influence of demographic (i.e. age and marital status) and lifestyle (i.e. physical activity, stress, alcohol intake, sleep medication use) variables.

SETTING

Respondents from the 1946-1951 cohort of the Australian Longitudinal Study on Women's Health who completed Survey 9 were included.

PARTICIPANTS

Data from n 7956 older women (mean age ± sd: 70·8 ± 1·5) were included.

RESULTS

70·2 % reported having at least one symptom and 20·5 % had between 3 and 5 symptoms of sleep problems (mean score ± sd: 1·4 ± 1·4, range 0-5). Adherence to dietary guidelines was poor with an average diet quality score of 56·9 ± 10·7 (range 0-100). Better adherence to dietary guidelines was associated with fewer sleep problem symptoms (β: -0·065, 95 % CI: -0·012, -0·005) and remained significant after adjusting for confounding influences.

CONCLUSIONS

These findings support the evidence that adherence to dietary guidelines is associated with symptoms of sleep problems in older women.

Does knowledge of sleep hygiene recommendations match behaviour in Australian shift workers? A cross-sectional study

OBJECTIVES

Shiftworkers routinely obtain inadequate sleep, which has major health consequences. Sleep hygiene describes a range of behaviours, lifestyle and environmental factors that can improve sleep. To date, limited research has examined sleep hygiene in shiftworkers. This study aimed to assess the sociodemographic and behavioural correlates of sleep hygiene knowledge and engagement with sleep hygiene practices in Australian shiftworkers.

STUDY DESIGN

An online, cross-sectional survey.

SETTING AND PARTICIPANTS

Australian adults from across multiple industries (n=588) who work shift work.

MEASURES

The online survey included questions regarding sleep hygiene knowledge and questions from modified versions of the Pittsburgh Sleep Quality Index and Sleep Hygiene Index.

RESULTS

Of the 588 participants, 52.9% reported having heard of 'sleep hygiene'. Of these participants, 77.5% reported understanding the term moderately, extremely or very well. Engagement with each sleep hygiene practice was varied. Common sleep hygiene practices were controlling the bedroom environment (eg, a cool, dark and quiet bedroom). Less common practices were avoiding light as bedtime approaches. Logistic regressions revealed that shiftworkers who had heard of sleep hygiene were more likely to engage in sleep hygiene practices and had better sleep quality compared with those who had not heard of sleep hygiene. Increased engagement in sleep hygiene practices did not predict the likelihood of individuals reporting better sleep quality.

CONCLUSIONS

Shiftworkers demonstrated varied knowledge, understanding and engagement with individual sleep hygiene practices. Future research should focus on the development of sleep hygiene interventions that accommodate the unique challenges of shift work to optimise sleep.

Prevalence, Trends, and Correlates of Joint Patterns of Aerobic and Muscle-Strengthening Activity and Sleep Duration: A Pooled Analysis of 359,019 Adults in the National Health Interview Survey 2004-2018

BACKGROUND

Physical activity (PA) and sleep duration have established associations with health outcomes individually but tend to co-occur and may be better targeted jointly. This study aimed to describe the cross-sectional prevalence, trends, and population characteristic correlates of activity-sleep patterns in a population-representative sample of US adults from the National Health Interview Survey (2004-2018).

METHODS

Participants (N = 359,019) self-reported aerobic and muscle-strengthening activity and sleep duration. They were categorized as "meeting both"/"meeting PA only"/"meeting sleep only"/"meeting neither" of the 2018 US PA guidelines and age-based sleep duration recommendations. Trends in activity-sleep patterns were analyzed using weighted multinomial logistic regression, and correlates were identified using weighted binary Poisson regressions, with P ≤ .001 considered significant.

RESULTS

"Meet sleep only" was most prevalent (46.4%) by 2018, followed by "meet neither" (30.3%), "meet both" (15.6%), and "meet PA only" (7.7%). Many significant sociodemographic, biological, and health-behavior correlates of the activity-sleep groups were identified, and the direction and magnitude of these associations differed between groups.

CONCLUSIONS

Public health campaigns should emphasize the importance of both sufficient PA and sleep; target women and older adults, current smokers, and those with lower education and poorer physical and mental health; and consider specific barriers experienced by minority ethnic groups.

A Time to Rest, a Time to Dine: Sleep, Time-Restricted Eating, and Cardiometabolic Health

Cardiovascular disease (CVD) poses a serious health and economic burden worldwide. Modifiable lifestyle factors are a focus of research into reducing the burden of CVD, with diet as one of the most investigated factors. Specifically, the timing and regularity of food intake is an emerging research area, with approaches such as time-restricted eating (TRE) receiving much attention. TRE involves shortening the time available to eat across the day and is associated with improved CVD outcomes compared with longer eating windows. However, studies that have examined TRE have not considered the impact of sleep on CVD outcomes despite recent evidence showing that sleep duration can influence the timing and amount of food eaten. In this article, we argue that as TRE and sleep influence each other, and influence the same cardiometabolic parameters, experiencing inadequate sleep may attenuate any positive impact TRE has on CVD. We examine the relationship between TRE and CVD, with sleep as a potential mediator in this relationship, and propose a research agenda to investigate this relationship. This will provide necessary evidence to inform future interventions aimed at reducing the burden of CVD.