The Development and Validation of the Health Belief Model for Shift Workers (HBM-SW) Scale.

OBJECTIVE: Shift work is associated with circadian misalignment, sleep loss, and suboptimal health behaviors, which may contribute to longer term negative health outcomes. To inform future interventions for shift workers, the present study aimed to develop and evaluate the Health Belief Model for Shift Workers (HBM-SW) scale. METHODS: The HBM-SW development involved a seven-step process, including a literature review, expert panel analysis, cognitive interviews with shift workers, and a trial with a pilot sample of shift workers (n = 153). Utilizing exploratory factor analysis for factor identification and item reduction, the developed scale loaded on seven factors in line with the theoretical framework of the Health Belief Model: Perceived Threat, Perceived Severity, Perceived Benefits, Perceived Barriers, Cues to Action, Self-efficacy, and Health Motivation. Validation of the scale was conducted utilizing Pittsburgh Sleep Quality Index, International Physical Activity Questionnaire, and Food Frequency Questionnaire. RESULTS: The pilot sample had an average age of 34.0 (18.0) years, was majority female (54.2%), with an average of 8.0 (11.0) years shift work experience. The HBM-SW showed good - excellent (α = 0.74-0.93) internal consistency and moderate - good (ICC = 0.64-0.89) test re-test reliability. Using health behavior outcome measures, the HBM-SW scale showed meaningful correlations with sleep quality, sleep duration, diet quality and leisure time physical activity, and acceptable validity and reliability. Further testing should be conducted in a larger sample to facilitate confirmatory factor analysis. CONCLUSIONS: The developed Health Belief Model for Shift Workers scale is likely beneficial for use in future studies of interventions for shift workers.

"I need to be alert at night to provide care": Factors associated with problematic sleep among young Australian caregivers.

OBJECTIVES: There is increased recognition that young people (<25 years) may occupy a carer role for family or others with health conditions or disability. This is often in addition to study and social activities. This means competing demands on time, and insufficient sleep. Our aim was to determine the contribution of caring duties to problematic sleep in young carers. METHODS: A survey of Australian carers was conducted, including questions on demographics, characteristics of the carer and care recipient, and sleep quality and quantity. Participants were eligible if they reported sleep time <7 hr or dissatisfaction with their sleep, and were aged 15-24 years. RESULTS: A total of 110 participants (71.8%_female = 79, 15-17 years = 62, 18-24 years = 48) were included in analysis; 55.5% (n= 61) reporting dissatisfaction with their sleep and 62.7% (n= 69) reporting typically less than 7 hr sleep per night. Sleep duration was significantly shorter for those who reported 1-2 or ≥3 awakenings to provide care, compared with no awakenings (p_< .05). Sleep quality, as described by scores on the Pittsburgh Sleep Quality Index (PSQI) was also significantly worse for those who were frequently awoken by their care recipient (p < .05). Worrying about the care recipient, being woken by the care recipient, and listening out for the care recipient were the most frequently identified factors impacting on sleep. CONCLUSION: Young carers experience reduced sleep duration and poor sleep quality. Strategies to alleviate the burden of care work on young carer's sleep would benefit the health and safety of this group.

A Deep Learning Approach to Classify Sitting and Sleep History from Raw Accelerometry Data during Simulated Driving.

Prolonged sitting and inadequate sleep can impact driving performance. Therefore, objective knowledge of a driver's recent sitting and sleep history could help reduce safety risks. This study aimed to apply deep learning to raw accelerometry data collected during a simulated driving task to classify recent sitting and sleep history. Participants (n = 84, Mean ± SD age = 23.5 ± 4.8, 49% Female) completed a seven-day laboratory study. Raw accelerometry data were collected from a thigh-worn accelerometer during a 20-min simulated drive (8:10 h and 17:30 h each day). Two convolutional neural networks (CNNs; ResNet-18 and DixonNet) were trained to classify accelerometry data into four classes (sitting or breaking up sitting and 9-h or 5-h sleep). Accuracy was determined using five-fold cross-validation. ResNet-18 produced higher accuracy scores: 88.6 ± 1.3% for activity (compared to 77.2 ± 2.6% from DixonNet) and 88.6 ± 1.1% for sleep history (compared to 75.2 ± 2.6% from DixonNet). Class activation mapping revealed distinct patterns of movement and postural changes between classes. Findings demonstrate the suitability of CNNs in classifying sitting and sleep history using thigh-worn accelerometer data collected during a simulated drive. This approach has implications for the identification of drivers at risk of fatigue-related impairment.

Informal management of health and safety risks associated with alarm response by Australian firefighters.

Fire-fighters use informal strategies to manage risks to health and safety during operations. It is not known whether such strategies are used during the high-risk alarm response period. The aim of this study was to determine if informal risk management strategies are employed by Australian firefighters during the alarm response procedure, and if these strategies differ between salaried and retained personnel. Forty-six metropolitan firefighters (all male; mean age 38 years ± 10 years; 22 salaried; 24 retained) participated in semi-structured group interviews. A general inductive data analysis approach revealed that firefighters use multiple informal risk management strategies. Some similar themes were reported by both salaried and retained personnel, for example leveraging team dynamics, communication about sleep and fatigue, stress adaptation, informal debriefs, and enhancing physical preparedness. These findings could be used by fire services to tailor risk management approaches during the alarm response period. Practitioner summary: Identifying informal risk management strategies firefighters use during alarm response will allow their development, refinement and dissemination, and may help other firefighters and emergency service workers to manage these risks. This qualitative study reveals multiple informal strategies that firefighters employ during alarm response to keep themselves and their team-mates safe.

The effect of a short burst of exercise during the night on subsequent sleep.

When on-call workers wake during the night to perform work duties, they may experience reduced alertness and impaired performance as a result of sleep inertia. After performing their duties, on-call workers may have the opportunity to return to sleep. Thus, it is important that sleep inertia countermeasures do not affect subsequent sleep. Exercise may be a suitable countermeasure; however, the impact on subsequent sleep is untested. Healthy participants (n = 15) completed three conditions in a counterbalanced order: sedentary, low-intensity exercise or high-intensity exercise, performed for 2 min upon awakening. Sleep was recorded 2 hr later using polysomnography, the Karolinska Sleepiness Scale was administered to measure subjective sleepiness, and core body temperature was measured continuously. Results indicate there was no effect of condition on most sleep variables; however, three variables had small differences, with longer total sleep time (p = .006), higher sleep efficiency (p = .006) and shorter N3 latency (p < .001) in the low-intensity exercise condition. There was no difference in subjective sleepiness (p = .124) or core body temperature (p = .216) 90 min after the exercise intervention. These results indicate that using a short burst of exercise to counteract sleep inertia when woken during the night may be a suitable countermeasure for on-call workers who not only need to be alert upon waking but also need quality sleep when returning to bed. Future research could include participants of other ages and health statuses to investigate whether the results are generalizable.

What Factors Influence the Sleep of On-call Workers?

Objective: On-call work is becoming increasingly common in response to service demands. This study had two aims; 1) describe the demographic profile of on-call workers in Australia, and 2) establish the impacts of on-call work on workers' sleep. Methods: A cross-sectional study was conducted using an online questionnaire completed by Australian on-call workers (n = 228) from various professions. The questionnaire included items on i) demographic and work characteristics, ii) rumination about on-call factors, iii) sleep quantity and quality. Analyses were conducted using mixed effects ordinal regression and multivariable logistic regression. Results: Workers slept <7 hours per night when on-call (80%), and reported sleep was impacted on-call even when no-calls were received (56%). On-call workers rated interruptions to family/leisure time (70%), missing a call (69%), preplanning in case of a call (69%), and not able to make plans (67%) as the main factors they ruminated about. Female on-call workers were more likely to think about the likelihood of being called, report frequent thoughts about what they would need to do if called, and think about interruptions to family/leisure time as a result of a call. Younger workers were more likely to think about the likelihood of being called compared to older adults, however middle-aged workers were less likely to plan for a call compared to younger workers. Conclusions: This study is the first to describe Australia's on-call population, including factors that specifically impact sleep. Future studies should implement tailored education and support strategies to address the unique challenges facing on-call workers.

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

Introduction: Inadequate sleep is a major public health concern, with large economic, health, and operational costs to Australia. Despite the implementation of public sleep health campaigns, approximately 40% of Australian adults do not obtain the recommended 7-9 hours of sleep. Thus, while people may know how much sleep is required, this knowledge may not be adequately translated to actual sleep behavior. Consequently, this study aims to examine the discrepancy between knowledge of sleep recommendations and self-reported sleep behaviors.Methods: A sample of 1265 Australian adults (54% female, aged 18-65) completed a phone interview as part of the 2017 National Social Survey and were asked questions about their knowledge of sleep guidelines and their actual sleep behavior. Binary logistic regression was used to determine the factors associated with awareness of sleep recommendations and whether this corresponded with reported sleep duration.Results: The final sample size was 998. Although 94% of the sample were aware of current sleep recommendations, 23% of participants did not self-report regularly obtaining 7-9 h sleep per night. These participants were less likely to want to obtain more sleep, less likely to view sleep as a priority before stressful events, and less likely to self-report good health.Conclusion: Although a majority of the sample were aware of sleep recommendations, almost a quarter of the participants' behavior did not align with their knowledge. Future sleep health campaigns should consider options beyond education, including emphasis on practical strategies and modifiable lifestyle factors to assist individuals to obtain the recommended amount of sleep.

Salivary cortisol profiles of on-call from home fire and emergency service personnel.

Working on-call with a night call resulted in a depressed (lower) cortisol awakening response (CAR) peak and post-awakening cortisol area under the curve with respect to ground (AUCG) the following day compared to when off-call. This may be due to exposure to noise, physical exertion, and stressful events during night callouts. There was no anticipatory effect to working on-call in any of the cortisol measures examined. This study, of male fire and emergency service workers who operate on-call from home, had two aims: (1) examine CAR and diurnal cortisol profile following a night on-call with a call, on-call without a call, and off-call; and, (2) explore whether there is an anticipatory effect of working on-call from home on diurnal cortisol profiles. Participants wore activity monitors, completed sleep and work diaries and collected seven saliva samples a day (0 min, 30 min, 60 min, 3 h, 6 h, 9 h, and 12 h after final awakening) for one week. CAR peak, reactivity and area under the curve with respect to increase (AUCI), post-awakening cortisol AUCG, diurnal cortisol slope and AUCG, and mean 12-h cortisol concentrations were calculated. The final analysis included 26 participants for Aim 1 (22 off-call nights, 68 nights on-call without a call, and 20 nights on-call with a call) and 14 participants for Aim 2 (25 days leading up to a night off-call and 92 days leading up to a night on-call). Generalized estimating equations models were constructed for each variable of interest. Aim 1: CAR peak and post-awakening cortisol AUCG were 8.2 ± 3.4 nmol/L and 5.7 ± 2.4 units lower, respectively, following a night on-call with a call compared to an off-call night. Aim 2: the day before a night on-call was not a significant predictor in any model. The lower CAR peak and post-awakening cortisol AUCG following a night on-call with a call compared to following an off-call night may be due to exposure to noise, physical exertion, and stressful events during night callouts. The lack of difference between the day before a night on-call and the day before an off-call night suggests there may not be an anticipatory effect on cortisol when on-call from home.

Barriers and Enablers to Modifying Sleep Behavior in Adolescents and Young Adults: A Qualitative Investigation.

OBJECTIVE: Many young adults obtain less than the recommended sleep duration for healthy and safe functioning. Behavior change interventions have had only moderate success in increasing sleep duration for this cohort. This may be because the way young adults think about sleep, including their willingness and ability to change sleep behavior, is unknown. The purpose of the present study was to determine what changes, if any, young adults are willing to make to their sleep behavior, and to identify factors that may enable or prevent these changes. PARTICIPANTS: Fifty-seven young adults (16-25 years; 57% female) took part in focus groups addressing (a) willingness to change, (b) desired outcomes of change, and (c) barriers to change in regards to sleep behavior. METHODS: An inductive approach to data analysis was employed, involving data immersion, coding, categorization, and theme generation. RESULTS: Participants were willing to change sleep behavior, and had previously employed strategies including advancing bedtime and minimizing phone use, with limited success. Desired changes were improved waking function, advanced sleep onset, optimized sleep periods, and improved sleep habits. Barriers to making these changes included time demands, technology use, difficulty switching off, and unpredictable habits. Young adults want to improve sleep behavior and waking function; this is an important first step in modifying behavior. Notably, participants wanted more efficient and better quality sleep, rather than increasing sleep duration. CONCLUSION: The reported barriers to sleep, particularly using technology for social purposes, will require innovative and specialized strategies if they are to be overcome.

The effects of anticipating a high-stress task on sleep and performance during simulated on-call work.

On-call work is used to manage around the clock working requirements in a variety of industries. Often, tasks that must be performed while on-call are highly important, difficult and/or stressful by nature and, as such, may impact the level of anxiety that is experienced by on-call workers. Heightened anxiety is associated with poor sleep, which affects next-day cognitive performance. Twenty-four male participants (20-35 years old) spent an adaptation, a control and two counterbalanced on-call nights in a time-isolated sleep laboratory. On one of the on-call nights they were told that they would be required to do a speech upon waking (high-stress condition), whereas on the other night they were instructed that they would be required to read to themselves (low-stress condition). Pre-bed anxiety was measured by the State Trait Anxiety Inventory form x-1, and polysomnography and quantitative electroencephalogram analyses were used to investigate sleep. Performance was assessed across each day using the 10-min psychomotor vigilance task (09:30 hours, 12:00 hours, 14:30 hours, 17:00 hours). The results indicated that participants experienced no significant changes in pre-bed anxiety or sleep between conditions. However, performance on the psychomotor vigilance task was best in the high-stress condition, possibly as a result of heightened physiological arousal caused by performing the stressful task that morning. This suggests that performing a high-stress task may be protective of cognitive performance to some degree when sleep is not disrupted.

Working (longer than) 9 to 5: are there cardiometabolic health risks for young Australian workers who report longer than 38-h working weeks?

PURPOSE: The average Australian working week in middle-aged and older workers exceeds government recommendations. Long working weeks are associated with poor health outcomes; however, the relationship between long working weeks and health in young Australian workers is unknown. METHODS: Data were drawn from the 22-year follow-up of the Western Australian Pregnancy Cohort (Raine) Study in Perth, Western Australia. Information was available from 873 young adults about working hours per week, shift work and sleep duration. Blood samples provided measures of cardiometabolic risk (CMR) factors. RESULTS: Almost one-third (32.8%) of young workers reported > 38 h working weeks. This was commonly reported in mining and construction industries for males; health and social assistance, mining and retail trade industries for females. CMR factors including increased waist circumference, higher fasting plasma glucose and reduced HDL cholesterol were associated with > 38 h working weeks. These relationships were not moderated by gender or by BMI for glucose and HDL cholesterol. Total sleep time was significantly lower in both male and female workers reporting > 38 h working weeks, but did not mediate the relationships seen with CMR factors. CONCLUSIONS: These findings point to early associations between > 38 h working weeks and CMR risk, and highlight the potential benefit of making young employees aware of the health associations with working arrangements to reduce the longer-term relationships seen with working hours and poor cardiometabolic health in population studies.

The impact of sleep restriction while performing simulated physical firefighting work on cortisol and heart rate responses.

PURPOSE: Physical work and sleep restriction are two stressors faced by firefighters, yet the combined impact these demands have on firefighters' acute stress responses is poorly understood. The purpose of the present study was to assess the effect firefighting work and sleep restriction have on firefighters' acute cortisol and heart rate (HR) responses during a simulated 3-day and 2-night fire-ground deployment. METHODS: Firefighters completed multiple days of simulated physical work separated by either an 8-h (control condition; n = 18) or 4-h sleep opportunity (sleep restriction condition; n = 17). Salivary cortisol was sampled every 2 h, and HR was measured continuously each day. RESULTS: On day 2 and day 3 of the deployment, the sleep restriction condition exhibited a significantly higher daily area under the curve cortisol level and an elevated cortisol profile in the afternoon and evening when compared with the control condition. Firefighters' HR decreased across the simulation, but there were no significant differences found between conditions. CONCLUSION: Findings highlight the protective role an 8-h sleep opportunity between shifts of firefighting work has on preserving normal cortisol levels when compared to a 4-h sleep opportunity which resulted in elevated afternoon and evening cortisol. Given the adverse health outcomes associated with chronically high cortisol, especially later in the day, future research should examine how prolonged exposure to firefighting work (including restricted sleep) affects firefighters' cortisol levels long term. Furthermore, monitoring cortisol levels post-deployment will determine the minimum recovery time firefighters need to safely return to the fire-ground.

Acute Psychophysiological Relationships Between Mood, Inflammatory and Cortisol Changes in Response to Simulated Physical Firefighting Work and Sleep Restriction.

This study examined how changes in wildland firefighters' mood relate to cytokine and cortisol levels in response to simulated physical firefighting work and sleep restriction. Firefighters completed 3 days of simulated wildfire suppression work separated by an 8-h (control condition; n = 18) or 4-h sleep opportunity (sleep restriction condition; n = 17) each night. Firefighters' mood was assessed daily using the Mood Scale II and Samn-Perelli fatigue scale. Participants also provided samples for the determination of salivary cortisol and pro- (IL-6, IL-8, IL-1ß, TNF-α) and anti-inflammatory (IL-4, IL-10) cytokine levels. An increase in the positive mood dimension Happiness was related to a rise in IL-8 and TNF-α in the sleep restriction condition. A rise in the positive mood dimension Activation among sleep restricted firefighters was also related to higher IL-6 levels. An increase in the negative mood dimension Fatigue in the sleep restriction condition was associated with increased IL-6, TNF-α, IL-10 and cortisol levels. In addition, an increase in Fear among sleep restricted firefighters was associated with a rise in TNF-α. Elevated positive mood and immune activation may reflect an appropriate response by the firefighters to these stressors. To further understand this relationship, subsequent firefighting-based research is needed that investigates whether immune changes are a function of affective arousal linked to the expression of positive moods. Positive associations between negative mood and inflammatory and cortisol levels to physical work and restricted sleep provide useful information to fire agencies about subjective fire-ground indicators of physiological changes.

The acute physiological stress response to an emergency alarm and mobilization during the day and at night.

The purpose of this study was to investigate the acute physiological stress response to an emergency alarm and mobilization during the day and at night. Sixteen healthy males aged 25 ± 4 years (mean ± SD) spent four consecutive days and nights in a sleep laboratory. This research used a within-participants design with repeated measures for time, alarm condition (alarm or control), and trial (day or night). When an alarm sounded, participants were required to mobilize immediately. Saliva samples for cortisol analysis were collected 0 min, 15 min, 30 min, 45 min, 60 min, 90 min, and 120 min after mobilization, and at corresponding times in control conditions. Heart rate was measured continuously throughout the study. Heart rate was higher in the day (F(20,442) = 9.140, P < 0.001) and night (F(23,459) = 8.356, P < 0.001) alarm conditions compared to the respective control conditions. There was no difference in saliva cortisol between day alarm and day control conditions. Cortisol was higher (F(6,183) = 2.450, P < 0.001) following the night alarm and mobilization compared to the night control condition. The magnitude of difference in cortisol between night control and night alarm conditions was greater (F(6,174) = 4.071, P < 0.001) than the magnitude of difference between the day control and day alarm conditions. The augmented heart rate response to the day and night alarms supports previous observations in field settings. Variations in the cortisol responses between conditions across the day and night may relate to differences in participants' ability to interpret the alarm when sleeping versus when awake.

Fighting fire and fatigue: sleep quantity and quality during multi-day wildfire suppression.

This study examined firefighters' sleep quantity and quality throughout multi-day wildfire suppression, and assessed the impact of sleep location, shift length, shift start time and incident severity on these variables. For 4 weeks, 40 volunteer firefighters' sleep was assessed using wrist actigraphy. Analyses revealed that the quantity of sleep obtained on fire days was restricted, and pre- and post-sleep fatigue ratings were higher, compared to non-fire days. On fire days, total sleep time was less when: (i) sleep location was in a tent or vehicle, (ii) shifts were greater than 14 h and (iii) shifts started between 05:00 and 06:00 h. This is the first empirical investigation providing objective evidence that firefighters' sleep is restricted during wildfire suppression. Furthermore, sleep location, shift length and shift start time should be targeted when designing appropriate controls to manage fatigue-related risk and preserve firefighters' health and safety during wildfire events. Practitioner Summary: During multi-day wildfire suppression, firefighters' sleep quantity was restricted, and pre- and post-sleep fatigue ratings were higher, compared to non-fire days. Furthermore, total sleep time was less when: (i) sleep occurred in a tent/vehicle, (ii) shifts were >14 h and (iii) shifts started between 05:00 and 06:00 h.

Associations between firefighters' physical activity across multiple shifts of wildfire suppression.

The aim of this study was to examine the associations between firefighters' physical activity levels across consecutive wildfire suppression shifts and to determine whether sleep duration moderated these associations. Forty volunteer firefighters (31 males, 9 females) wore an activity monitor to concurrently measure physical activity and sleep duration. Sedentary time and time spent in light- (LPA), moderate- (MPA), and vigorous-intensity physical activity (VPA) during each shift were determined using monitor-specific cut points. During any given shift, every additional 60 min spent in LPA was associated with 7.2 min more LPA and 27.6 min MPA the following shift. There were no other significant positive or negative associations. No significant moderating effect of total sleep time was observed. Firefighters are able to maintain and/or increase their physical activity intensity between consecutive shifts. Further research is needed to understand firefighters pacing and energy conservation strategies during emergency wildfire deployments. Practitioner Summary: To examine associations between firefighters' physical activity levels across consecutive shifts during a multi-day emergency wildfire and determine whether sleep duration moderated these associations. Firefighters are able to maintain and/or increase their physical activity intensity between consecutive shifts. No significant moderating effect of total sleep time was observed.

How much advance notice do workers need? A review and theoretical framework for determining advance notice periods for unpredictable work.

Regulatory guidance materials for fatigue management typically advise that employees be provided with days or weeks of advance notice of schedules/rosters. However, the scientific evidence underpinning this advice is unclear. A systematic search was performed on current peer reviewed literature addressing advance notice periods, which found three relevant studies. A subsequent search of grey literature to determine the quality of evidence for the recommendation for advance notice periods returned 37 relevant documents. This review found that fatigue management guidance materials frequently advocated advance notice for work shifts but did not provide empirical evidence to underpin the advice. Although it is logical to suggest that longer notice periods may result in increased opportunities for pre-work preparations, improved sleep, and reduced worker fatigue, the current guidance appears to be premised on this reasoning rather than empirical evidence. Paradoxically, it is possible that advance notice could be counterproductive, as too much may result in frequent alterations to the schedule, particularly where adjustments to start and end times of the work period are not uncommon (e.g., road transport, rail). To assist organisations in determining the appropriate amount of advance notice to provide, we propose a novel theoretical framework to conceptualise advance notice.

'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.

Move the night way: how can physical activity facilitate adaptation to shift work?

Shift work, involving night work, leads to impaired sleep, cognition, health and wellbeing, and an increased risk of occupational incidents. Current countermeasures include circadian adaptation to phase shift circadian biomarkers. However, evidence of real-world circadian adaptation is found primarily in occupations where light exposure is readily controlled. Despite this, non-photic adaptation to shift work remains under researched. Other markers of shift work adaptation exist (e.g., improvements in cognition and wellbeing outcomes) but are relatively unexplored. Timeframes for shift work adaptation involve changes which occur over a block of shifts, or over a shift working career. We propose an additional shift work adaptation timeframe exists which encompasses acute within shift changes in markers of adaptation. We also propose that physical activity might be an accessible and cost-effective countermeasure that could influence multiple markers of adaptation across three timeframes (Within Shift, Within Block, Within Work-span). Finally, practical considerations for shift workers, shift work industries and future research are identified.