Category

Focus on Fatigue

Issue #60 – July/August 2019

Welcome to Focus on Fatigue!

Winter is now well underway here in Australia. That means the sun is slow to wake up in the morning and it goes to bed much earlier. For shift workers, the idea of having such a regular routine of waking and sleeping is far from the norm. Working non-standard hours, and trying to get adequate sleep during off-times, comes with huge challenges which can, at times, seem overwhelming.

In this month’s Focus on Fatigue we’ll be talking about Shift Work Disorder. What is it? And what can shift workers do to reduce its symptoms?

Best wishes for the month ahead,
The FRMS Team

 

InterDynamics Pty Ltd
320 Adelaide Street Brisbane Qld 4000
Tel +61 7 3229 8300
www.interdynamics.com

Views expressed in articles and links provided are those of the individual authors, and do not necessarily represent the views of InterDynamics (except where directly attributed).

Featured Articles

Shift Work Disorder

Most people who work shifts will struggle, at times, with periods of insomnia or excessive sleepiness. Such struggles can be said to be a ‘normal’ reaction to staying awake when your body wants to sleep and trying to sleep when your body wants to be awake. However, for some shift workers, the demands of shift work result in ongoing sleep challenges that begin to interfere with both work and family life. This is where the term ‘Shift Work Disorder’ begins to apply.

What is Shift Work Disorder?

Shift Work Disorder (SWD) is a Circadian Rhythm Sleep Disorder. The National Sleep Foundation lists the symptoms of SWD as follows:

  • Excessive sleepiness when you need to be awake, alert, and productive.
  • Insomnia, or the inability to sleep when you need to. This can mean trouble falling asleep, or waking up before you’ve slept sufficiently.
  • Sleep that feels unrefreshing or insufficient.
  • Difficulty concentrating.
  • Lack of energy.
  • Irritability or depression.
  • Difficulty with personal relationships.

It is estimated that around 10% of all shift workers suffer from SWD. The disorder can develop in those who work night shifts, rotating shifts, or early morning shifts. The symptoms inherent in SWD can result in sufferers experiencing a state of chronic sleep deprivation, which has significant implications for health, productivity and safety.

Coping with Shift Work Disorder

It is important that sufferers of SWD make sleep a priority in order to reduce the impact of symptoms. For example:

  • Maintain a sleep diary – this may help identify problem patterns that can be adjusted and give an indication of how much sleep you’re achieving in each 24-hour period.
  • Regulating light exposure – minimise exposure to light on the way home from night shift, but get lots of bright light before the start of shifts to suppress melatonin.
  • Bedtime rituals – following regular bedtime rituals, such as putting on pyjamas and brushing teeth, can be a subtle way of telling the brain it is time for sleep.
  • Maintain good sleep hygiene – even if you are sleeping during the day, it is important that your bedroom is cool, quiet and dark.
  • Do Not Disturb – put a sign on the front door to prevent disturbances.
  • Work hours – If possible, decrease the number of night shifts in a row to a more tolerable level.
  • Napping – If possible, plan a nap before or during your shift. This will help to improve alertness.

When Behavioural Interventions are Not Enough

For times when the symptoms of SWD persist, despite good behavioural practices, there are a number of pharmacological interventions that can be used to increase wakefulness at work and assist with sleeping at home. However, these substances often come with side effects and other concerns (such as issues with tolerance). It is important to discuss the pros and cons of such interventions with your doctor.

References

  • Australasian Sleep Association (2019) Shift work sleep disorder. https://www.sleep.org.au/documents/item/2830. Accessed: 05/06/19.
  • National Sleep Foundation (2019) Shift work disorder symptoms. https://www.sleepfoundation.org/shift-work-disorder/what-shift-work-disorder/shift-work-disorder-symptoms. Accessed: 05/06/19.
  • Cleveland Clinic (2019) Shift work sleep disorder: Management and treatment. https://my.clevelandclinic.org/health/diseases/12146-shift-work-sleep-disorder/management-and-treatment. Accessed: 05/06/19.

 

In the News

Provided below are a selection of articles from around the web on the issues associated with fatigue. We hope you find them useful and interesting.

Video: Matt Walker: Sleep is Your Superpower
Matt Walker, TED Talks, April 2019
Sleep is your life-support system and Mother Nature’s best effort yet at immortality, says sleep scientist Matt Walker. In this deep dive into the science of slumber, Walker shares the wonderfully good things that happen when you get sleep — and the alarmingly bad things that happen when you don’t, for both your brain and body. Learn more about sleep’s impact on your learning, memory, immune system and even your genetic code — as well as some helpful tips for getting some shut-eye.

Article: Neurologist Exposes Dangers Of Sleep-Tracking Apps
Jan Cortes, Medical Daily, 10 June 2019
If you’ve had trouble sleeping at some point in your life, then you are probably one of the many people who have turned to sleep-tracking applications in hopes of getting “enough sleep.” And at the best of times, this might have worked for you. But does the use of these apps have any negative effects?

Welcome to Focus on Fatigue!

There are a lot of things we struggle to remember. People’s names, the title of that book someone recommended, where we put our car keys. Then there are all those events we’d like to forget, like that embarrassing thing we did in high school (we ALL have at least a few of those memories). Thankfully, for most of us, the not-so-great memories are far outweighed by the many happy moments that are scattered throughout a life. Wedding days, the births of children, the time we performed perfectly at a piano recital or recalled every fact needed to get an A on an important exam.

In this month’s Focus on Fatigue, we’ll be looking at the different types of memory, how memories are formed, and how to ensure the memories we want to hold onto last a lifetime. Unsurprisingly, it’s all a matter of a good night’s sleep.

Best wishes,
The FRMS Team

 

InterDynamics Pty Ltd
320 Adelaide Street Brisbane Qld 4000
Tel +61 7 3229 8300
www.interdynamics.com

Views expressed in articles and links provided are those of the individual authors, and do not necessarily represent the views of InterDynamics (except where directly attributed).

Featured Articles

Sleeping to Remember

In the past, sleep has often been viewed as wasted time. But as more and more research is done on sleep, we’ve begun to realise just how active our brains are during those hours of slumber. Just because we’re not conscious of what our brain is doing during sleep, doesn’t mean there is nothing going on. One of the many ways in which our brain is helping us while we sleep is in the consolidation and regulation of memories.

There are different types of memory, including short-term memory (remembering a new phone number long enough to write it down) and long-term memory. Within long-term memory are explicit memory (conscious) and implicit memory (unconscious). Explicit memory can then be broken down into episodic memory (memories of events that have happened to you) and semantic memory (your general knowledge about the world). Finally, implicit memory can be broken down in priming (the word ‘bread’ is likely to make you think of the word ‘butter’ but not the word ‘doctor’) and procedural memory (learned motor skills such as how to drive a car). That’s a lot of different types of memory for the brain to keep track of!

How do memories form?

When you drift off to sleep at night the neurons in your hippocampus come alive, performing a replay of the memories from that day. The hippocampus and the neocortex spend time sifting through these memories, deciding what needs to be stored and what can be forgotten. Important memories are then stored in the neocortex so they can be recalled in the future. This replay only happens during sleep. Which means, if you don’t get enough sleep, those memory you’re making won’t be consolidated and you’re less likely to retain them.

Remembering

When you recall a memory (either consciously or unconsciously) you are reactivating the neurons where that memory is stored. These neurons are connected through synapses, which can be strengthened or weakened depending on how often you recall the memory (the ability of the brain to make these ongoing changes is called synaptic plasticity). This is why you can remember events from long ago, such as the birth of a child or the first time you were stung by a bee. Because the memories are important to you, or caused a strong emotional reaction. By remembering them many times, you’ve created strong connections between the neurons where the memories are stored.

Forgetting

What did you have for breakfast on the second Tuesday of last month? You probably knew the answer to that question the next day, maybe even the day after. But as time passed you’ve probably forgotten. What happened to those memories?

This is another way in which sleep helps us to regulate memories. Not only does it help us retain important memories, but it helps us forget memories that aren’t important. This is done through a process called ‘synaptic homeostasis’ (it’s still a hypothesis currently, but the evidence is mounting). The theory suggests that during sleep there is an overall weakening of the synaptic connections throughout the brain. Memories that had weak connections in the first place will be forgotten, while those with strong connections will continue to be retained. This effectively ‘cleans the slate’ so that we’re able to learn new information and make new memories upon waking.

Sleep stages and memory type

Studies have found evidence that different stages of sleep are important for different types of memory. For example, REM (Rapid Eye Movement) sleep is thought to be important for emotional memories (the painful sting of that bee) and for procedural memories (driving a car, playing the piano). Meanwhile, slow-wave sleep (deep, restorative sleep) is important for episodic memories. Motor learning has also been linked to the lighter stages of sleep.

The research is still in its early stages here, but the implication is clear: if you want good consolidation of all memory types, you need to be cycling through all the various stages of sleep.

Learning new information

The learning of new information is often described as having three parts: the acquisition of new information, the consolidation of this information through memory formation (occurs during sleep) and recall of the information. While we’ve already discussed how a lack of sleep effects the consolidation of new information, there are a number of other ways in which sleep deprivation interferes with learning. For example:

  • Lack of focus, attention and vigilance
  • Over-worked neurons no longer able to coordinate information properly
  • Reduced ability to access previously learned information
  • Judgement becomes impaired
  • Negatively impacts mood, making learning more difficult

While we may not have all the answers on how sleep and memory work, the evidence is clear. If you want to lay down good memories, clear out unimportant memories, and have access to the information you’ve taken the time to learn – get a good night’s sleep.

References

  • Blanco, W., Pereira, C. M., Cota, V. R., Souza, A. C., Rennó-Costa, C. and Santos, S. (2015) Synaptic Homeostasis and Restructuring across the Sleep- Wake Cycle. PLoS Computational Biology, 11(5): e1004241.
  • Kirszenblat, L. (2017, October 19) Sleep deprivation: Why your brain needs to go to sleep. Queensland Brain Institute. Retrieved from https://qbi.uq.edu.au.
  • Harvard Medical School (2007) Sleep, learning, and memory. Retrieved from http://healthysleep.med.harvard.edu.
  • Squire, L. R., Genzel, L., Wixted, J. T. and Morris, R. G. (2019) Memory consolidation. Cold Spring Habor Perspectives in Biology, 7, a021766.

InterDynamics News

FAID Quantum Utilised in Research on U.S. Police Rosters

A research team at Washington State University recently published a paper in which FAID Quantum was used in an investigation of the association between police fatigue and complaints made by members of the public. The details are given below:

Riedy, S. M., Dawson, D., and Vila, B. (2019) U.S. police rosters: Fatigue and public complaints. Sleep, 42(3), 1-10.

Abstract

Study Objectives: Recent experimental research indicates a substantial impact of shift work related fatigue on police officers’ encounters with the public. In recent years, biomathematical models of fatigue have provided a new way to identify potential relationships between working time arrangements and job performance. This study focused on public complaints against police officers and determined whether the odds of a public complaint were associated with work schedules and/or a biomathematical model’s predictions of fatigue and sleepiness.

Methods: N = 144 police officers from two municipal police departments in the United States reported shift start times, shift hours, court hours, and public complaints each duty day during study participation. A biomathematical model of fatigue (FAID Quantum) predicted sleep duration and sleep timing and inferred fatigue and sleepiness for 15 744 shifts. Fatigue, sleepiness, 24 hr sleep estimates, and work schedule were tested as predictors of public complaints.

Results: Greater fatigue, greater sleepiness, and less sleep in the 24 hr prior to a shift increased the odds of a public complaint (F ≥ 9.14, p < 0.01). Working back-to-back night shifts increased the odds of a public complaint (OR = 4.27, p < 0.01), particularly when off-duty court hours were worked between the night shifts (OR = 4.73, p < 0.01).

Conclusions: On-duty fatigue and sleepiness, sleep obtained prior to a shift, and working night shifts were strongly associated with public complaints. Off-duty court appearances reduced sleep between night shifts and further increased the odds of a public complaint. The results suggest that off-duty court hours should be limited between night shifts and duty schedules should be considered when scheduling court appearances.

In the News

Provided below are a selection of articles from around the web on the issues associated with fatigue. We hope you find them useful and interesting.

Video: The benefits of a good night’s sleep
Shai Marcu, TED-Ed (5 January 2015)
It’s 4am, and the big test is in 8 hours. You’ve been studying for days, but you still don’t feel ready. Should you drink another cup of coffee and spend the next few hours cramming? Or should you go to sleep? Shai Marcu defends the latter option, showing how sleep restructures your brain in a way that’s crucial for how our memory works.

Article: Memory ‘brainwaves’ look the same in sleep and wakefulness
University of Birmingham (9 October 2018)
Identical brain mechanisms are responsible for triggering memory in both sleep and wakefulness, new research at the University of Birmingham has shown. The study sheds new light on the processes used by the brain to ‘reactivate’ memories during sleep, consolidating them so they can be retrieved later.

Welcome to Focus on Fatigue!

The past couple of months seem to have been a study of extremes. Extreme cold in some parts of the world, and extreme heat in others. As someone who is firmly located in the heat, I know firsthand that such extremes can have a significant effect on how well we sleep at night.

So, whatever part of the world you’re in, I hope you’re managing to get a good night’s sleep, whether that’s bundled up in blankets or cover-free with the ceiling fan on high.

Best wishes,
The FRMS Team

 

 

InterDynamics Pty Ltd
320 Adelaide Street Brisbane Qld 4000
Tel +61 7 3229 8300
www.interdynamics.com

Views expressed in articles and links provided are those of the individual authors, and do not necessarily represent the views of InterDynamics (except where directly attributed).

Featured Articles

Working with Risk

When we talk about Fatigue Risk Management, we are talking about managing increases in the risk of accident and injury associated with increases in fatigue. It’s all about keeping people safe. One part of managing such risk is knowing when accidents at work are mostly likely to occur.

A number of studies have examined this issue in detail and the following trends have been identified.

Risk across different shifts

There is a consistent tendency for the relative risk of accidents to be lowest for morning shifts, increased for afternoon shifts, and highest for night shifts (on 8-hour shift systems). Across a number of studies, the relative risk for incidents was 30% higher on the night shift than on the morning shift.

Risk over successive night shifts

In a group of studies that examined the risk of accident over the course of four consecutive night shifts, it was found that risk increased substantially for each night. Indeed, the risk of having an accident on the fourth night was 36% higher than it was on the first night. This same increase was found in the day shift, but to a much milder degree.

Risk over successive hours of work

Risk of accident tends to increase exponentially after the 8th hour on shift. Relative to this first 8-hour period, 10-hour shifts are associated with a 13% increase in risk. The increase in risk for a 12-hour shift is 27%.

Risk between shift breaks

The risk of having an accident rises in the time between breaks, with accidents most likely to happen in the 30 minutes prior to a rest break.

What about the Circadian Rhythm?

The circadian rhythm is an internal body clock that cycles between periods of sleepiness and alertness throughout the day and night. It’s one of the reasons we get sleepy after the sun goes down, but it’s also responsible for that post-lunch slump that makes us want to take a nap. For most adults, the biggest dips in energy occur between about 2am and 4am, then again between 1pm and 3pm. Therefore, it seems natural that there would be an increase in risk of injury for shift workers who are working during the circadian dip in the early hours of the morning.

While this is far from proven, there is some evidence to support the theory. For example, a study of truck drivers found a major peak in accidents occurring around 3am. This increase was not necessarily due to drivers falling asleep at the wheel, but seemed to be due more to a decrease in driving performance. So, if you are working during this time of the morning, it may be useful to schedule a break if possible.

References

  • Folkard, S. and Tucker, P. (2003) Shift work, safety and productivity. Occupational Medicine, 53, 95-101.
  • Folkard, S. (1997) Black times: Temporal determinants of transport safety. Accident Analysis and Prevention, 29(4), 417-430.
  • Folkard, S., Lombardi, D. A. and Tucker, P. T. (2005) Shift work: Safety, sleepiness and sleep. Industrial Health, 45, 2-23.

In the News

Provided below are a selection of articles from around the web on the issues associated with fatigue. We hope you find them useful and interesting.

Article: 8 weird facts about sleep science learned in 2019 alone
JR Thorpe, Bustle (6 February 2019)
Maybe it’s because 2018 was a hell of a year and we all want to spend most of 2019 in sweet, sweet slumber, but there was a lot of research published in January this year about sleep. Like, a lot of research. This article checks out what we’ve learned so far.

Article: The connection between sleep and pain
Lydia Denworth, Psychology Today (5 February 2019)
A new study reveals how sleep loss changes brain processing to increase pain.

Welcome to Focus on Fatigue!

It’s a brand new year and that means a fresh start! Every January provides a great opportunity to reflect on the habits of the previous year, and plan for ways we can improve over the coming twelve months. For example, if you haven’t been getting enough sleep, then committing to some extra shuteye is an easy way to increase energy, improve focus and maintain health. So, let’s all get the year off to a great start… by taking a nap!

Before you grab that blanket and pillow, this month’s Focus on Fatigue will be investigating the how and why of the metabolic disturbances that are often associated with shift work.

Best wishes for the year ahead,
The FRMS Team

 

InterDynamics Pty Ltd
320 Adelaide Street Brisbane Qld 4000
Tel +61 7 3229 8300
www.interdynamics.com

Views expressed in articles and links provided are those of the individual authors, and do not necessarily represent the views of InterDynamics (except where directly attributed).

Featured Articles

Shift Work and the Metabolism

All humans are wired by nature to be awake during the day and asleep at night. This fundamental truth, set by our circadian rhythm, is something we cannot ever truly escape. However, our society requires that a sizable portion of us work in shifts through both the day and night. One of the major consequences of this requirement is the increase in metabolic disorders seen among shift workers.

How does shift work disrupt the metabolism?

Shift work disrupts the metabolism in several ways, for example:

  • Ghrelin/Leptin – Ghrelin is a hormone produced when we need food. Leptin is produced when we have eaten enough. Shift work produces a desynchrony between these hormones. This leads to feelings of hunger in the middle of the night, especially for unhealthy food, without the stop needed to prevent overeating. Hence, the increased risk of obesity seen in shift workers.
  • Estrogen/Testosterone – There is an ageing component to these hormones. Older people have more difficulty adapting to shift work than younger people.
  • Inflammation – The HPA axis regulates stress hormones (the fight or flight response), so disruption makes people less able to deal with stress. This produces a state of chronic inflammation in the system. Obesity plays into inflammation (through fat tissue signalling) and makes it worse.
  • DNA Damage – Melatonin is believed to be a scavenger of free radicals. When the regulation of melatonin is upset it causes damage to the DNA, which the body then has less ability to repair. This leads to increased cancer risk.

In other words, there are many parts and players in this very complex system. They are all supposed to be in sync. Shift work, however, can upset the balance.

Study of Food Timing and Metabolomics in Shift Workers

A study conducted by Washington State University examined the effects of simulated shift work on the circadian rhythm and metabolic processes. Participants (stereotypically healthy people without sleep disorders) were separated into two groups. Those who underwent a series of three simulated night shifts, and those who underwent days shifts. Meals were timed at regular intervals throughout the night or day depending on which shift schedule the participants followed. Following the three ‘shifts’, all participants were kept awake for 24-hours in a constant environment (ie. lighting, posture, food, food timing, etc was kept constant) with regular blood samples taken to test hormone levels.

The Results

At the end of the three days of simulated night shifts, the onset of the hormone melatonin (a major indicator of the body’s circadian rhythm) shifted by only 1.5 hours. This is far short of the 12-hour shift that would be necessary for true ‘adjustment’ to the night shift hours. This was also true for a number of other hormones known to be closely related to the circadian rhythm, such as cortisol.

However, many of the hormones involved in the metabolic processes flipped their readings by the full 12 hours, lining up with the night shift schedule.

This produced a profound desynchrony between the circadian rhythm and the metabolic system. One system was convinced it was day, while the other had decided it was night.

What does this mean?

It has been thought that the metabolic disruption experienced by shift workers was due primarily to the misaligned biological clock. However, this may not be the whole story. It may be that other ‘clocks’ within the body are also involved.

This study showed that hormones involved in the metabolic processes may quickly align themselves to different sleep/wake and feeding/fasting schedules, even though the circadian rhythm is not so easily shifted.

Therefore, during night shifts it is possible that the biological clock will appear to be signalling night-time, where other peripheral oscillators (other clocks within the body) are signalling day-time, causing internal desynchronization.

Reference

  • van Dongen, H. (2018) Metabolomics: A new window on peripheral oscillators. Sleep Down Under 2018. 17-20 October 2018. Brisbane, Australia.

 

In the News

Provided below are a selection of articles from around the web on the issues associated with fatigue. We hope you find them useful and interesting.

Video: Researchers gain new perspectives on how shift work disrupts metabolism
KXLY, YouTube (13 July 2018)
A new study impacts millions of people who don’t work a typical nine to five job. KXLY4’s Ariana Lake reports. Including an interview with Dr Hans van Dongen of the WSU Elson S. Floyd College of Medicine.

Article: How shift work disrupts metabolism
Science Daily (9 July 2018)
A new study has brought scientists closer to finding out why working night shifts increases your risk of developing diabetes and other metabolic disorders. The study revealed that just three days of being on a night shift schedule will disrupt metabolism. This disruption appears to be driven by separate biological clocks (so-called peripheral oscillators) in the liver, gut and pancreas, rather than the brain’s master clock.

Welcome to Focus on Fatigue!

Another big year will soon draw to a close. Down here in Australia, that means summer sun and beach fun. Wherever you are in the world, the staff of InterDynamics would love to take this opportunity to wish you and your family a joyful festive season and a safe, well-rested start to the new year.

Best wishes,
The FRMS Team

 

 

InterDynamics Pty Ltd
320 Adelaide Street Brisbane Qld 4000
Tel +61 7 3229 8300
www.interdynamics.com

Views expressed in articles and links provided are those of the individual authors, and do not necessarily represent the views of InterDynamics (except where directly attributed).

Featured Articles

Long sleepers: Are they getting too much of a good thing?

The saying goes that everything is good for you in moderation. This holds true for most things. Too much food makes us overweight and too little robs us of energy, but the right amount keeps us healthy and active. Too little exercise leads to all sorts of nasty health issues and too much gives us blisters and bad knees. A moderate amount of exercise keeps us fit and strong. What about the third pillar of the healthy living triad? Sleep.

Most of us know the importance of sleep, perhaps because we are now bombarded with information every other day about the dangers of sleep deprivation. Hence we strive, and sometimes succeed, to achieve the recommended 7-9 hours. There are some people, on the other hand, who not only love their sleep but are experts at getting it. Nine hours a night? Ten, perhaps? No problem. But are all these snoozing hours actually doing more harm than good? Is too much sleep bad for you?

As it turns out, a number of researchers have asked this question over the last few decades and most agree the short answer is yes. Too much sleep is, indeed, a bad thing. Much of the research in this area has looked at the issue in terms of mortality rates. They’ve found that, over a long-period of time (anywhere from 4-25 years, depending on the study) people who sleep a lot are more likely to die than those who get the recommended amount of sleep. People who sleep too little are also more likely to die, but the association is actually stronger for the long sleepers than it is for the short sleepers. This is especially true for older adults (45+ years).

Why is sleeping a lot bad for you?

This is the part where research has yet to provide an adequate answer. In fact, some suggest that sleeping a lot may be a symptom of ill-health rather than the cause. In other words, does sleeping too much cause health problems, or do health problems make people sleep a lot? This is an area which requires more research.

How much is too much sleep?

Here is where things get even trickier. The Sleep Health Foundation states that “most adults require between 7 and 9 hours a night to feel properly refreshed and function at their best the next day.” Many of the studies quoted in the research use ‘more than 8 hours’ as the basis for their analyses, which would make nine hours of sleep seem like a risky proposition. However, one meta-analysis found that the association between long sleep and mortality seemed to strengthen as the hours of sleep increased. So, if you’re sleeping between 7 and 9 hours each night and you feel refreshed and ready to get out of bed each morning, you’re probably in the clear. If you regularly sleep longer than 9 hours, however, it might be a good idea to have a health check-up.

Does this mean I should avoid ‘catching up’ on sleep?

You absolutely should continue to catch up on sleep if you’ve been deprived (caveat: it’s always better to avoid becoming sleep deprived in the first place). These studies were looking at people who regularly sleep for longer than the recommended hours each night. For them, excessive sleep was the norm, not the exception.

I’m a long sleeper! What should I do?

If you regularly sleep longer than nine hours every night, it might be a good idea to chat to your local health care professional. It’s possible that the quality of your sleep is low and that’s why you spend so much time asleep, or that the extra sleep is caused by some underlying health issue. It’s also possible that, genetically speaking, that’s just the way you were made.

References

  • Youngstedt, S. D. and Kripke, D. F. (2004) Long sleep and mortality: Rationale for sleep restriction. Sleep Medicine Reviews, 8(3), 159-174.
  • Ding, D., Rogers, K., van der Ploeg, H., Starnataskis, E. and Bauman, A. E. (2015) Traditional and emerging lifestyle risk behaviors and all-cause mortality in middle-aged and older adults: Evidence from a large population-based Australian cohort. PLOS Medicine, 12(12), e1001917. DOI: 10.1371/journal.pmed.1001917.
  • Gallicchio, L. and Kalesan, B. (2009) Sleep duration and mortality: A systematic review and meta-analysis. Journal of Sleep Research, 18, 148-158.
  • Cappuccio, F. P., D’Elia, L., Strazzullo, P. and Miller, M. A. (2010) Sleep duration and all-cause mortality: A systematic review and meta-analysis of prospective studies. Sleep, 33(5), 585-592.

InterDynamics News

Conferences and presentations

Sleep Down Under

Last month InterDynamics attended the Sleep Down Under Conference in Brisbane, Australia. Sleep Down Under was the 30th Annual Scientific Meeting of the Australasian Sleep Association (ASA) and Australasian Sleep Technologists Association (ASTA). Staff who attended enjoyed hearing all the latest research on topics such as nutrition for shift workers, individual management, and the wonders of the circadian rhythm.

Date: 17-20 October 2018
Venue: Brisbane Convention and Exhibition Centre, Brisbane, Australia

More information can be found on the conference website.

In the News

Provided below are a selection of articles from around the web on the issues associated with fatigue. We hope you find them useful and interesting.

Video: Can you get too much sleep?

SciShow, YouTube (24 December 2016)

Are you someone who likes to hit the snooze button four or five times before waking up? Do you have to be physically pulled out of bed every morning? Do you ever wonder if that’s normal and healthy? Well, this episode is for you!

Article: Why eight hours a night isn’t enough, according to a leading sleep scientist

Georgia Frances King, Quartz (10 June 2018)

For something that we spend a third of our lives doing (if we’re lucky), sleep is something that we know relatively little about. To set the record straight about being horizontal, Quartz spoke to Daniel Gartenberg, one of the world’s most-talked-about sleep scientists.

Welcome to Focus on Fatigue,

Sometimes in life we have little choice but to keep on keeping on, even when we’re tired. Perhaps we’re in the car, still an hour away from home. Or maybe we need to finish a project and absolutely cannot miss the deadline. Is there an effective way to keep our alertness and performance levels up long enough to reach our goal safely? That is the question we’ll be investigating in this month’s Focus on Fatigue.

The FRMS Team

 

InterDynamics Pty Ltd
320 Adelaide Street Brisbane Qld 4000
Tel +61 7 3229 8300
www.interdynamics.com

Views expressed in articles and links provided are those of the individual authors, and do not necessarily represent the views of InterDynamics (except where directly attributed).

Featured Articles

The Power of the Coffee Nap

In the midst of our busy working days (and working nights), many of us reach for a cup of coffee, or other caffeinated beverage, to counteract sleepiness. If the sleepiness reaches a high enough level, we may go even further and have a quick nap before returning to our task. But what would happen if we did both? Would combining the two techniques achieve an outcome greater than the sum of its parts?

What is a coffee nap?

Taking a coffee nap is a simple two-step process.

Step One: Drink a cup of coffee. This must be done quickly, so make sure it’s not too hot, or switch out your latte for an iced coffee, or a simple espresso shot. Drinking tea is not as good an option here simply because the caffeine content will not be high enough to achieve the desired effect.

Step Two: Take a nap. The nap itself should be no more than twenty minutes. This ensures you don’t enter the deeper stages of sleep, which would lead to grogginess (known as sleep inertia) upon waking. Setting an alarm on your phone is a great way to prevent oversleeping.

Why do coffee naps work?

Adenosine is a molecule produced by your brain when you’re awake and active. As adenosine builds up, it fits into receptors in the brain, making you tired. The caffeine molecule is similar in shape so, when you drink a cup of coffee, the caffeine makes its way to your brain and competes with the adenosine for access to the same receptors. The more caffeine molecules reaching the receptors, the greater the alerting effect.

Here’s where the nap can help. Sleep naturally flushes adenosine out of your brain, making way for more caffeine molecules to find available receptors. The caffeine takes about 30 minutes to be absorbed through your small intestine, pass into your bloodstream, and reach your brain. Therefore, if you have a 15-20 minute nap, the adenosine levels will be reduced just in time for the caffeine to sweep in and save the day. Hooray!

How well do coffee naps work?

The coffee nap has been found to be effective in a variety of situations, including:

  • preventing performance degradation on computer tasks for at least one hour
  • reducing sleepiness and improving performance in drivers during a monotonous afternoon drive in a car simulator for one hour
  • in a study of night shift workers, caffeine and naps were both found to improve performance on a vigilance task and decrease sleepiness, but the combination of the two had the greatest effect

It’s important to note that while coffee naps can alleviate sleepiness in the short term, they are not a replacement for adequate sleep, and the effects will wear off within a couple of hours.

What if I’m a bad napper?

Many people find it difficult to nap on command, especially during the day. However, the research has found that even a restful doze can help performance.

So, the next time you find yourself needing to go that extra hour or two before resting, try a coffee nap. It may just do the trick.

References

  • Hayashi, M., Masuda, A. and Hori, T. (2003) The alerting effects of caffeine, bright light and face washing after a short daytime nap. Clinical Neurophysiology, 114(12), 2268-2278.
  • Reyner, L. A. and Horne, J. A. (1997) Suppression of sleepiness in drivers: Combination of caffeine with a short nap. Psychophysiology, 34(6), 721-725.
  • Newman, R. A., Kamimori, G. H., Wesensten, N. J., Picchioni, D. and Baklin, T. J. (2013) Caffeine gum minimized sleep inertia. Perceptual and Motor Skills, 116(1), 280-293.
  • Schweitzer, P. K., Randazzo, A. C., Stone, K., Erman, M., and Walsh, J. K. (2006) Laboratory and field studies of naps and caffeine as practical countermeasures for sleep-wake problems associated with night work. Sleep, 29(1), 39-50.
  • Stromberg, J. (2015) Scientists agree: Coffee naps are better than coffee or naps alone. Vox. https://www.vox.com/2014/8/28/6074177/coffee-naps-caffeine-science (Accessed: 1 August 2018)

In the News

Provided below are a selection of articles from around the web on the issues associated with fatigue. We hope you find them useful and interesting.

Article: Health Check: What are ‘coffee naps’ and can they help you power through the day

Chin Moi Chow, The Conversation (3 April 2017)

Caffeine and napping have something in common. Both make you feel alert and can enhance your performance, whether that’s driving, working or studying. But some people are convinced that drinking a coffee before a nap gives you an extra zap of energy when you wake up.

Video: Why do coffee naps recharge you so well?

SciShow, YouTube (23 June 2018)

A short video explaining the benefits of coffee naps, and why they work so well.

Welcome to Focus on Fatigue!

We’ve all experienced moments in our lives when we’ve felt the urge to go to sleep at an inappropriate time. It could happen in a meeting, during a movie, or when we hit that mid-afternoon slump. At these times one of the methods we tend to use to keep the sandman away is to get up and walk around, maybe even do some stretches. This sort of low-level exercise often helps increase our alertness long enough to finish the task at hand. In this issue of Focus on Fatigue we’ll look at how useful low-level exercise can be in assisting shift workers to maintain alertness and concentration during their shift.

The FRMS Team

 

InterDynamics Pty Ltd
320 Adelaide Street Brisbane Qld 4000
Tel +61 7 3229 8300
www.interdynamics.com

Views expressed in articles and links provided are those of the individual authors, and do not necessarily represent the views of InterDynamics (except where directly attributed).

Featured Articles

Exercising on the Job

Every shift worker knows what it’s like to experience moments of fatigue in the workplace. These moments can be caused by issues such as sleep deprivation, working at odd hours, or by the need to complete monotonous tasks for a long period of time. A variety of behaviours have proved effective at reducing fatigue, including strategic napping, exposure to bright light, and eating a healthy snack. Another behaviour which can be useful is low-level exercise. While this topic has not received extensive research attention, several studies have shed light on how exercise at work can be used by night shift workers.

Sato and his colleagues (2010) conducted a study in which participants worked between the hours of 10pm and 8am. They performed tasks requiring sustained attention while sitting down. The participants were separated into two groups, those who spent three minutes exercising for each hour of work, and those who did not exercise at all. It was found that the exercisers performed their work better than those who did not exercise. This was true even though the exercisers felt just as fatigued and sleepy as the non-exercisers.

Another study examined the ability of young people to stay awake for up to 31 hours using varying degrees of physical activity. Simply being spoken to (no physical activity) was the least effective, followed by sitting up and then standing up. Wakefulness was enhanced most by standing and doing knee bends. Therefore, the more intense the level of activity, the more effective it was in helping participants maintain wakefulness.

It is, of course, important for individuals to assess what sort of activity is most helpful for them based on the type of work they do. Indeed, the inclusion of low-level exercise may be most helpful for those performing sedentary tasks, but less useful for shift workers who already move around while working.

What kind of exercises help?

The exercises performed by the participants of the Sato study were as follows:

  • Neck twisting – turning head from side to side;
  • Arm swinging – swinging outstretched arms around in circles;
  • Leaning backwards and forwards – bending at the waist;
  • Twisting the torso – lift arms up and bend at waist to one side, then the other;
  • Bending and stretching the knees – squatting and standing;
  • Side stretching the legs – squat down on one knee and stretch other leg straight out to the side;
  • Stretching the lower legs – stretch one straight leg out behind and bend front knee till a stretch is felt in the back leg;
  • Spreading the legs – lunging squats; and
  • Deep breathing – done while standing tall.

Each exercise was performed for approximately 20 seconds and was designed to be performed in a small space (within a radius of 1.5m).

Research

  • Bonnet, M. H. and Arand, D. L. (1999) Level of arousal and the ability to maintain wakefulness. Journal of Sleep Research, 8, 247-254.
  • Sato, T., Kubo, T., Ebara, T., Takeyama, H., Inoue, T., Iwanishi, M., Tachi, N., Itani, T. and Kamijima, M. (2010) Brief hourly exercise during night work can help maintain workers’ performance. Industrial Health, 48, 470-477.

In the News

Provided below are a selection of articles from around the web on the issues associated with fatigue. We hope you find them useful and interesting.

Article: A sleep doctor’s No. 1 tip for a great rest every night

Dr Michael J. Breus, MindBodyGreen (1 January 2018)

As a board-certified sleep specialist, I could share a copious amount of advice to enhance your sleep; however, if you choose only one thing to improve, make it getting 30 minutes of aerobic exercise.

Video: How exercise rewires your brain

Seeker, YouTube (9 July 2013)

Everyone knows exercise is good for your health, but new studies show it does more than flatten those abs– it physically alters your brain to better handle stress! Anthony shows us this hidden, and hugely beneficial impact of working out.

Welcome to Focus on Fatigue!

Here at Focus on Fatigue we spend a lot of time talking about the benefits of getting enough sleep and how everyone, shift workers and non-shift workers alike, should make sleep a priority. But what about those times when you have the opportunity to sleep but the sandman fails to show up? This can result in frustration and worry, especially as the minutes continue to tick by. In this issue of Focus on Fatigue we’ll be looking at insomnia: what it is and what shift workers can do to prevent it from becoming a problem.

The FRMS Team

 

InterDynamics Pty Ltd
320 Adelaide Street Brisbane Qld 4000
Tel +61 2 8404 0400 Ext 23
www.interdynamics.com

Views expressed in articles and links provided are those of the individual authors, and do not necessarily represent the views of InterDynamics (except where directly attributed).

Featured Articles

Insomnia and Shift Work

We’ve all experienced nights when we can’t get to sleep, no matter how long we lie in bed wishing it would happen. Other times we’ve woken up hours before dawn and not been able to go back to sleep. For some people, however, these sorts of sleeping difficulties are a nightly struggle and this is when the term ‘insomnia’ comes into play. Around 6% of the adult population meet the diagnostic criteria for insomnia. For shift workers, however, estimates rise as high as 20%. Insomnia is also a major component of shift work disorder.

Consequences of insomnia

The consequences of insomnia are varied, including psychosocial, occupational, health and economic repercussions. While those who suffer from insomnia are faced with the same symptoms as anyone experiencing sleep deprivation, such as daytime sleepiness and irritability, the long-term nature of insomnia introduces more far-reaching problems. Insomniacs tend to take more frequent sick leave and use health care resources more often. There is an increased risk of accident and, over time, an increase in the risk of developing depression, anxiety, and substance-related problems. In recent research, the sleep deprivation experienced in sleep disorders such as insomnia has also been linked to an increased risk of Alzheimer’s disease later in life.

How much sleep are insomniacs really getting?

One surprising finding of insomnia research is that most (but not all) people who suffer from insomnia have a surprisingly limited ability to accurately estimate the amount of sleep they’re getting. They will often overestimate their sleep onset latency (how long it takes them to fall asleep) and underestimate their total sleep time (compared to objective measures of sleep such as a polysomnograph). In contrast, normal sleepers are usually able to perceive their sleep more accurately. A review of the research surrounding this issue concluded that such misperceptions are likely caused by misinterpreting sleep as wakefulness, worry causing a distortion in perceived time, and an increase in brief awakenings in the initial onset of sleep. These misperceptions regarding sleep do not, however, decrease the distress caused by the disorder; nor does it relieve the adverse outcomes associated with it.

Preventing insomnia in shift workers

A recent review of non-pharmacological preventions for fatigue and insomnia in shift workers included the following interventions:

  • Napping – A 20-minute nap during a shift can improve alertness, vigilance, reaction times, and performance and decrease the risk of accidents. Although, sleep inertia should be taken into consideration upon waking.
  • Nutrition – The use of caffeine at the start of a shift can be helpful, as well as high-protein meals and maintaining a wholefood diet. Regular normal day and night eating patterns should be maintained wherever possible.
  • Light – Planned exposure to bright light can assist shift workers in making adjustments to their internal clock to reduce sleepiness during work shifts.
  • Lifestyle training – Holistic training programs can help give shift workers tools to cope with the challenges of shift work, including good nutrition, managing fatigue, and sleep hygiene.
  • Cognitive and behavioural interventions – A variety of behaviours, such as exercise, can help to prevent insomnia. Shift workers can also use interventions such as timing their work breaks, social interaction during breaks, and sensory stimulation.

Research

  • Vallieres, A., Azaiex, A., Moreau, V., LeBlanc, M., and Morin, C. (2014) Insomnia in shift work. Sleep Medicine, 15(12), 1440-1448.
  • Belcher R, Gumenyuk V, Roth T. (2015) Insomnia in shift work disorder relates to occupational and neurophysiological impairment. Journal of Clinical Sleep Medicine, 11(4), 457–465.
  • Harvey, A. and Tang, N. (2012) (Mis)Perception of sleep in insomnia: A puzzle and a resolution. Psychological Bulletin, 138(1), 77-101.
  • Richter, K., Acker, J., Adam, S., and Niklewski, G. (2016) Prevention of fatigue and insomnia in shift workers—a review of non-pharmacological measures. The EMPA Journal, 7(16).

In the News

Provided below are a selection of articles from around the web on the issues associated with fatigue. We hope you find them useful and interesting.

Article: If you have insomnia, don’t sleep more, sleep efficiently, study on soldiers finds

J. P. Lawrence (24 June 2017) San Antonia Express News

A new study on sleep suggests the best way to cure insomnia is to get out of bed. Often those with insomnia spend long hours in bed, but few actually spent sleeping. Spending more time tossing and turning can actually make insomnia worse, because over time, people begin to associate bedtime with frustration and anxiety, the researcher said.

Video: How to sleep better – Fixing insomnia

PictureFit (26 January 2017) YouTube

Learn about insomnia and how you can fix it today. Insomnia is a huge problem for many people around the world. Roughly 95% of all Americans deal with insomnia in one point of their lives. It’s time to fix it and get a good night’s rest!

Welcome to Focus on Fatigue,

It’s a brand-new year and many of us will spend time this month deciding what areas of life or work we wish to focus on in the coming twelve months. There is, however, one important thing we should all do before making any important decisions: get a good night’s sleep. This month in Focus on Fatigue we’ll look at how sleep deprivation can affect the decisions we make.

The FRMS Team

 

InterDynamics Pty Ltd
320 Adelaide Street Brisbane Qld 4000
Tel +61 2 8404 0400 Ext 23
www.interdynamics.com

Views expressed in articles and links provided are those of the individual authors, and do not necessarily represent the views of InterDynamics (except where directly attributed).

Featured Articles

Sleep and Decision Making

Many studies have attempted to explore the effects of sleep deprivation on decision making. So far researchers have found that sleep deprivation will produce the greatest detrimental effects under the following conditions:

Dull, monotonous tasks

The more basic and monotonous a task is, the more likely it is that sleep deprivation will make you perform badly. Performance can be improved if the person is motivated to do well.

Boredom or lack of motivation

Interesting tasks seem to be largely immune to sleep deprivation, as long as they are not too complex and are rule-based. However, even interesting tasks become dull and monotonous over time. Again, unless the motivation to do well is present, performance will begin to suffer.

Complex tasks with changing circumstances

The prefrontal cortex is the part of the brain that helps you to focus your attention on a given task for long periods of time. It also deals with novelty and the unexpected. During wakefulness, it is one of the hardest working parts of the brain.

This area of the brain is restored by deep sleep, which means that when you are sleep deprived, the prefrontal cortex is one of the first parts of the brain to suffer. Therefore, you could be affected in any of the following ways:

  • Impaired language skills-communication
  • Lack of innovation
  • Inflexibility of thought processes
  • Inappropriate attention to peripheral concerns or distraction
  • Over-reliance on previous strategies
  • Unwillingness to try out novel strategies
  • Unreliable memory for when events occurred
  • Change in mood including loss of empathy with colleagues
  • Inability to deal with surprise and the unexpected

The consequences of impaired decision making in the presence of sleep deprivation have been seen time and again throughout history. As summarised by Harrison and colleagues (2000):

“It is perhaps just a coincidence that some of the most renowned man-made disasters or near disasters concerning nuclear power plants, such as Chernobyl, Three Mile Island … all occurred in the early morning and involved human error in failing to contain otherwise controllable but unexpected and unusual mechanical or control room malfunctions. With all four, experienced control room managers misdiagnosed and failed to appreciate the extent of the fault and then embarked on courses of action that were inappropriate and continued to persevere in this way in spite of clear indications that their original assessment was wrong.” (p. 247)

Will coffee help?

When a person is in a position where they are sleep deprived and forced to make complex decisions, it is understandable that they will reach for a cup of coffee to help them cope with the demands that are being placed upon them. While the effects of coffee in such a situation have not been well researched, one study did find that a moderate dose of caffeine did nothing to reverse the effects of sleep deprivation in this sort of situation. In other words, drinking coffee may make you feel more alert, but it may not do anything to help you think more clearly.

What if I take a nap?

A nap does have the benefit of improving alertness, performance and mood. However, the nap will always be followed by a period of sleep inertia. How long this inertia lasts depends on the severity of the sleep deprivation, the length of the nap, and the sleep stage the person was in right before they woke up.

If a worker’s scheduled nap is interrupted by an emergency requiring a quick response with a high level of performance, that person may end up responding to the emergency while suffering the effects of sleep inertia. In this case, their job performance may be worse than if they had not napped at all.

Therefore, if this possibility exists, it will be necessary to weigh up the benefits of improved alertness and performance during regular work, with the potential likelihood of an emergency occurring during the period when sleep inertia is an issue.

Research

  • Harrison, Y. and Horne, J. A. (2000) The impact of sleep deprivation on decision making: A review. Journal of Experimental Psychology: Applied, 6(3), 236-249.
  • Killgore, W. D. S., Balkin, W. J. and Wesensten, N. J. (2006) Impaired decision making following 49 h of sleep deprivation. Journal of Sleep Research, 15, 7-13.
  • Killgore, W. D. S., Lipizzi, E. L., Kamimori, G. H. and Balkin, T. J. (2007) Caffeine effects on risky decision making after 75 hours of sleep deprivation. Aviation, Space and Environmental Medicine, 78, 957-962.
  • Whitney, P., Hinson, J. M., Jackson, M. L. and Van Dongen, H. P. A. (2015) Feedback blunting: Total sleep deprivation impairs decision making that requires updating based on feedback. SLEEP, 38(5), 745-754.

In the News

Provided below are a selection of articles from around the web on the issues associated with fatigue. We hope you find them useful and interesting.

Article: Research shows sleep loss impedes decision making in crisis

Will Ferguson (7 May 2015) Washington State University

WSU researchers created a laboratory experiment that simulates how sleep loss affects critical aspects of decision making in high-stakes, real-world situations. Their results provide a new understanding of how going without sleep for long periods can lead doctors, first responders, military personnel and others in a crisis situation to make catastrophic decisions.

Welcome to Focus on Fatigue,

One of the main challenges shift workers face is keeping their energy levels high through those long shifts, especially at night. Maintaining a healthy diet is a great way to assist in this area. However, with another year drawing to a close and all those silly season celebrations close at hand, it can be difficult to eat a good variety of healthy foods. In this month’s Focus on Fatigue, we’ll look at the impact of shift work on our nutrition, and ways in which shift workers can stay healthy and alert at work.

Here at InterDynamics, we would also like to take this opportunity to wish you and your family a very happy Christmas and New Year period.

The FRMS Team

 

 

InterDynamics Pty Ltd
320 Adelaide Street Brisbane Qld 4000
Tel +61 2 8404 0400 Ext 23
www.interdynamics.com

Views expressed in articles and links provided are those of the individual authors, and do not necessarily represent the views of InterDynamics (except where directly attributed).

Featured Articles

Eating on the Job

Maintaining a healthy diet is one of the many challenges faced by shift workers around the globe. A number of the negative health consequences associated with shift work – such as obesity (especially abdominal obesity), type 2 diabetes and cardiovascular disease – also have poor diet as a risk factor.

There are many reasons why a healthy diet can be difficult to maintain when working shifts, including:

  • Lack of access to healthy food (in the middle of the night the only food available may come from a vending machine);
  • Lack of time/motivation for preparing food to bring in from home;
  • The need to eat quickly or while on the move;
  • Lack of time to eat at all due to work demands; and/or
  • Lack of appropriate food storage/preparation areas at work.

Nutrition and the Circadian Rhythm

The human circadian rhythm (our internal body clock) has a major influence on when we feel alert and when we feel sleepy. It turns out the circadian rhythm also play a part in when we feel hungry. This can be problematic for shift workers who finds themselves trying to eat ‘lunch’ at midnight. Indeed, shift-workers have been found to be more likely to develop gastric problems.

In one study, participants were asked to rate their appetite and food preferences during a 13-day period. It was found that appetite tended to be lowest at around 8am and peaked at 8pm, leading to the desire to eat a larger meal at night. It was suggested that this greater appetite before sleeping helps us to make it through the night without waking due to hunger, while the lack of hunger in the morning prevents us from being overly ravenous when we wake up. Another study looked at the appetite of shift workers who worked either day shifts, early morning shifts, or night shifts. It was found that those who worked the early morning shift tended to have the lowest appetites and were more likely to eat fatty foods.

In keeping with this idea that the body’s need for food decreases through the night to a low-point in the morning, shift workers have been found to use ‘nibbling behaviour’ during night-shifts, rather than eating full meals. Assuming they are nibbling on healthful foods, this may assist workers in consuming their daily requirement of calories in a more comfortable manner than if they attempted to eat a heavy meal in the middle of the night.

Food Choices

Shift workers have been found to have a tendency to eat more inflammatory diets than non-shift workers. This includes an increased consumption of calories, fats, proteins, carbohydrates, and sweets. They can also be less likely to consume vegetable and fruits, but more saturated fats, than their day-working counterparts.

Another study found that the food intake of night workers was more likely to be influenced by habit and time availability, than by hunger. They were more dependent on snacks than day workers, looked forward to their meals less and felt more bloated after eating. These effects were still present, to a lesser degree, on their rest days.

What can shift workers do to stay healthy?

Diabetes Australia has published a short guide to nutrition for shift workers. You can download the guide here. Below are some of the tips given for making sure your shift working nutrition plan is good for you:

  • Eat every 3-4 hours, including 3 main meals and 2-3 snacks in each 24-hour period
  • Eat according to the time of day: breakfast in the morning, lunch in the middle of the day and dinner in the evening
  • If you’re eating late at night, when you would normally be sleeping, aim for a snack that’s high in protein instead of a full meal
  • Eat a small meal after your shift so you don’t go to bed hungry
  • Keep an eye on your portion sizes
  • Drink more water than any other drink
  • Limit sugary drinks, alcohol and caffeine
  • Avoid caffeine within the six hours before going to sleep

The Shifting Nutrition guide also includes meal ideas and more information on the different types of food shift workers should aim to consume and in what quantities.

Research

  • Crispim, C. A., Waterhouse, J., Damaso, A. R., Zimberg, I. Z., Padilha, H. G., Oyama, L. M., Tufik, S. and de Mello, M. T. 2011) Hormonal appetite control is altered by shift work: A preliminary study. Metabolism Clinical and Experimental, 60, 1726-1735.
  • Diabetes Australia (2015) Shifting Nutrition: A Shift Workers Guide to Nutrition. Queensland Government.
    Hemio, K., Puttonen, S., Viitasalo, K., Harma, M., Peltonen, M. and Linstrom, J. (2015) Food and nutrient intake among workers with different shift systems. Ocuppational and Environmental Medicine, 72(7), 513-520.
  • Reinberg, A., Migraine, C., Apfelbaum, M., Brigant, L., Ghata, J., Vieux, N., Laporte, A. (1979) Circadian and ultradian rhythms in the feeding behaviour and nutrient intakes of oil refinery operators with shift-work every 3-4 days. Diabete & Metabolisme, 5(1), 33-41.
  • Scheer, F. A. J. L., Morris, C. J. and Shea, S. A. (2013) The internal circadian clock increases hunger and appetite in the evening independent of food intake and other behaviors. Obesity, 21, 421-423.
  • Sun, M., Feng, W., Wang, F., Li, P., Li, Z., Li, M., Tse, G., Vlaanderen, J., Vermeulen, R., and Tse, L. A. (2017) Meta-analysis on shift work and risks of specific obesity types. Obesity Reviews, doi: 10.1111/obr.12621.
  • Waterhouse, J., Buckley, P., Edwards, B. and Reilly, T. (2003) Measurement of, and some reasons for, differences in eating habits between night and day workers. The Journal of Biological and Medical Rhythm Research, 20(6), 1075-1092.
  • Wirth, M. D., Burch, J., Shivappa, N., Steck, S. E., Hurley, T. G., Vena, J. E. and Hebert, J. R. (2014) Dietary inflammatory index scores differ by shift work status: NHANES 2005 to 2010. Journal of Occupational and Environmental Medicine, 56(2), 145-148.

In the News

Provided below are a selection of articles from around the web on the issues associated with fatigue. We hope you find them useful and interesting.

Article: Shift work: How to stay healthy while working round the clock

The Guardian, 22 June 2017

Shift work: it’s complicated. Are you “working” when you’re asleep but at work? Should you be paid for being on call when you’re at home? Recent legal cases have looked at whether a sleepover shift is “working time” (and therefore, the worker should be entitled to the national minimum wage) and there’s new research on shift workers and their health too. A recent study found that delaying meals because of working shifts can mess with your internal body clock. But what if you can’t avoid shift work? What if your job kicks off in the evening and ends at dawn, and that’s just the way it is? Try these six ways to survive the slog.

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