Military personnel are subject to working and living conditions that may not follow a 'normal' routine when compared to civilian standards.
When on operations, soldiers' sleep routines will be based around a lull in battle or specific tasks.
This level of disruption may hinder mental and physical resilience, not only during their career but thereafter.
This article is supported by 127 cited references.
We shall cover the following points:
- Importance of sleep
- Sleep deprivation
- Effects of poor sleep
- Reasons for sleep issues
- Military sleep studies
- How to optimize sleep
Let's go back to basics and take a look at sleep, and it's importance.
Sleep Importance for Health
Scientists do not know for certain whether all creatures sleep, or certainly in a manner that is the same to humans, but all mammals do sleep.
Adults require around 7-8 hours of sleep every night and around 9 hours for teenagers if this number of hours is reduced, your body creates a sleep 'debt'. 
Very much like financial debt, what you take away today, needs to be repaid later down the line. Therefore, if you reduce your sleep each night, you will need a larger recovery period over the next few days.
And, by missing out on sustained periods of sleep you are likely to suffer from impaired cognitive function, reduce memory, there's the possibility of mood swings and even experiencing hallucinations.
Statistics on Sleep
Studies suggest that up to 80 million Americans suffer from serious sleep problems. These issues can be undiagnosed due to the person ignoring them or it is being missed by a medical professional. 
However, insufficient sleep is a global health concern and doesn't just affect the US.
A study from Finland saw that insufficient sleep was a long-standing concern, and it appeared to be more common in women than men. 
This pattern is also common among the Swedish population, with a report that 28% of women and 21% of men suffer from sleep problems. 
Similar results were also found from a survey conducted in Australia which reported that 28% of the participants were struggling with sleep and that the prevalence is as great as those found in studies from populations in the Northern Hemisphere. 
Statistics from The National Health Interview Survey suggest that adults sleep less than 6 hours within a 24 hour period, and these statistics also lay claim that adults were sleeping nearly 8 hours per 24 hours when the survey was first rolled out in 1977. 
When we look at this collection of data it is easy that it is a widespread issue, regardless of age, nationality, race, or gender.
What's the big deal about sleep deprivation?
Is Sleep Deprivation Dangerous?
The science and health experts say yes. 
But, let's look deeper into the sleep deprivation facts.
What is it about a lack of sleep that is so dangerous?
For a start there are the physical effects, then the physiological and mental effects, the latter being more difficult to detect.
The predominant symptom of sleep loss is feeling sleepy during the daytime, or the hours that you are awake. 
As we previously mentioned, there's a change of mood and reduced concentration of effects on memory functions.
You can detect these symptoms very easily. You know when you need more sleep as daily tasks tend to take more effort to complete.
The physiological symptoms my be more difficult to detect, particularly for the person it is affecting.
If they don't know about an underlying issue, this could mean that the person is suffering from a serious sleep problem and could potentially be undetected by a medical professional as that figure of 80 million Americans suggests.
So, wherein lays the danger?
Side Effects to Sleep Deprivation
Let's start off with the physical, more obvious symptoms, and the effects...
We all know the feeling.
Too many late nights working, or even binge-watching TV leads to feeling slightly disjointed from the real world, and while coffee or energy drinks may prop you up, you can feel it is a battle that will eventually be lost.
So let's look at some of the common effects that you may experience when suffering from fatigue that you may be able to recognize yourself, and try to rectify which have been outlined by the health services from the State of Victoria in Australia. 
- Chronic tiredness – unable to shake off the feeling of heavy eyes and yawning
- Headaches – a feeling of exhaustion or stress
- Dizziness – wandering in a daze and unsteady on your feet
- Aching muscles and weakness – feeling like they haven't recovered
- Slow reflexes, impaired co-ordination – a feeling of drunkenness
- Reduced appetite – a dynamic shift towards your eating behaviors
- Impaired immune system – feeling under the weather
- Problems concentrating and focussing - attention issues and forgetfulness
- Hallucinations – vision impairment and your mind playing tricks
You may not have realized but fatigue can manifest itself in many different ways, but you may have experienced any of these symptoms, maybe after a long shift at work, studying, or driving for instance.
What are the dangers?
Fatigue can be costly towards productivity as it can reduce a person's output.
However, where fatigue can pose the most risk is regarding the safety aspects of operating machinery or even impaired judgment towards making decisions that can have ever-lasting consequences.
An example of the dangers while operating machinery could be vehicular accidents.
It has been concluded in some studies that fatigue plays a role in up to 10% of road traffic accidents. Interestingly, that figure increases for free-way/motorway accidents. 
On the other end of the spectrum, people making judgments and decisions while deprived of sleep can pose a significant risk.
The investigations surrounding a number of significant events have concluded that a lack of sleep has played a major part in the accidents occurring, major events that have come to affect many people such as the Challenger Space Shuttle explosion, the Chernobyl disaster, and even oil spills. 
Thus highlighting the importance of sleep. Now put this into the context of battle.
It may come as no surprise to learn that The U.S Army recognized that approximately 9% of crashes involving wheeled vehicles that resulted in injury or death during both conflicts in the Gulf were attributed to a lack of sleep. 
Therefore, we can see that even being tired which may not be considered as a big deal by some, or a regular occurrence can lead to death.
In fact, The Traffic Accident Commission of Australia states that being awake for 17 hours would affect your driving to the same amount of being at the drink-drive limit.
By driving after 24 hours without sleep would then put your driving performance on par with your blood alcohol concentration being double the legal Australian limit. 
Let's now look at some of the hidden dangers that can be the result of sleep deprivation.
After all, figures from the U.S Department of Health and Human Services state that a lack of sleep is linked to almost half of all deaths in the USA. 
Cognitive development is theorized to start around the age of 2 with the capacity to coordinate two or more ideas starts to happen around the age of 4. This develops further around the age of 6 whereby the child has the ability to deal with more complex problems.
As age marches on, so does the development of thought, ideas, hypotheses, and concept generation. 
From the age of 12 and up to around 18, the person is developing more abstract, reasoning, logical thinking processes that can help form and question their own view of the world and how it operates. 
It is during adolescence and the early adult years where the recommended time asleep is at its peak (9 hours for every 24). 
So, is there a relationship between the early beginnings of complex thought and required sleep?
An analysis of 143 studies into the effects of sleep and cognitive performance found that overall sleep deprivation has a significant reduction in human functioning.
Furthermore, it was found that partial sleep deprivation (less than 6 hours of sleep per 24 hours for 5 consecutive days and night) was more damaging than long term and short term sleep deprivation. 
Those who are exposed to sleep deprivation are likely to experience a number of issues which do include cognitive decline and mood changes. 
What's the reason?
It is considered that a reduced level of alertness, attention and awake-state instability are some of the main reasons. And, it is thought that these slowed responses and inattentiveness is due to the person experiencing micro-sleeps, which are characterized by very short periods of electroencephalography (EEG) activity. 
This results in a person that fluctuates between not being fully asleep nor awake. 
Initial theories considered cognitive processes to remain intact beside the micro-sleeps, however, further investigation has seen a reduced cognitive capacity outside of the lapses. 
This behavior suggests that sleep loss has an effect on the prefrontal cortex of the brain which executes language, creativity, divergent thinking, and other executive functions such as working memory. 
This can result in difficulty of understanding and processing new tasks, and making decisions while seeing an increase of risk-taking alongside errors.
Obviously, this can have negative results when combined with professional activities such as machine operatives, medical workers, and those in the military where judgment can be impaired which was demonstrated when Air Force pilots were tasked with a simulated overnight air refueling task.
The study saw that after 19 hours of being awake, the pilots experienced degradation of visual perception and motor performance. 
You may wonder how a lack of sleep may influence obesity, after all, if you are awake longer, you are likely to be burning more calories, right?
Or, does being awake more lead to an increase of calorie consumption?
However, there's a distinct connection between shorter sleeping hours and a higher body mass index (BMI) as demonstrated by a 13-year study of 496 adult participants. 
The results saw that those who slept for less than 6 hours per 24 hours were 7.5 times more likely to be overweight and have a higher body mass index.
While on the opposite end of the spectrum, those who slept for nearly 8 hours per 24 displayed the lowest body mass index figures. 
Why is this?
Is it merely a case of having less sleep means you've got more time available to eat?
No, but, less sleep affects your appetite-related hormones. Namely leptin and ghrelin.
Too little sleep reduces the levels of leptin and increases the level of ghrelin.
Leptin is a hormone that suppresses appetite whereas ghrelin is a peptide that stimulates the appetite.
At least two separate studies have linked a sleeping restriction with these hormones as well as the sympathetic nervous system and hypothalamic hormones which are also linked to appetite which suggests why obesity is linked to the number of reduced sleeping hours.  
Furthermore, there's evidence that obesity also contributes to obstructive sleep apnea. It is thought that additional fat constricts the airways. 
Therefore, we are left with a vicious circle. To little sleep can contribute towards obesity, and obesity can contribute to sleep deprivation.
There's a distinct correlation between the trend of shorter sleeping habits alongside increases of obesity and diabetes throughout industrialized countries.
However, this just isn't an anecdotal analysis. There is growing evidence that supports chronic partial sleep loss is a contributing factor towards diabetes.
The research tells us that sleep deprivation can increase the sympathetic nervous system activity, as we mentioned in regards to obesity.
In addition, it can lead to increased levels of cortisol during the evening, which is a stress hormone and has been described as your body's alarm.
Then there's the increase in growth hormone during the day.
All of these metabolic effects can lead to an increase of insulin resistance along with reduced tolerance of glucose, as a result, this can increase the risk of developing diabetes. 
We previously covered the issues regarding obesity and lack of sleep.
There is a strong link between obesity, type 2 diabetes, and obstructive sleep apnea. The connected circle between obesity and sleep disorders becomes a triangle due to the proven association of diabetes. 
An experimental study found that those who slept for 5 hours of sleep or less per 24 hours were 2.5 times more likely to have diabetes than someone who sleeps 7 to 8 hours. Even topping up your sleep to 6 hours saw a 1.7 times chance of having diabetes with both groups suffering from sleep dysfunction having impaired glucose intolerance. 
This trend was also observed in a study of 11 men who reduced their sleep to just 4 hours per 24 over a period of 6 nights. The experiment led to impaired glucose tolerance. Interestingly, upon return to a normal and healthy level of sleep, their glucose tolerances returned to a healthy level.
Furthermore, obstructive sleep apnea and insulin resistance is also connected to high blood pressure.
There are clinical studies available that demonstrate a strong relationship between sleep loss, heart attacks, and even stroke. 
The studies also identify a link between the risk of cardiovascular disease, sleep disruption, and diabetes. 
As with obesity being a cause of sleep deprivation, and sleep deprivation contributing to an increased risk of obesity, cardiovascular diseases can also disrupt sleep quality. 
Once again, it seems we are faced with a chicken and egg scenario. However, there is compelling proof that obstructive sleep apnea causes high blood pressure. 
Furthermore, a study saw that even a day with little sleep (3.5 hours over a 24 hour period) results in blood pressure increases. 
In turn, this can then lead to coronary heart disease as a result of the increased sympathetic nervous system activity which serves as a common disorderly physiological process to cardiovascular-related diseases. 
More evidence has emerged from the Annals of Behavioral Medicine journal published in 2011 that connects a disruption of sleep affecting the communication of the brain and immune system consisting of endocrine hormones, cytokines, and autonomic nerves. This sleep disruption inhibits the function of this network which in turn increases inflammation which is linked to cardiovascular disease. 
Additional data suggests that having a duration of 5 hours of sleep or less for every 24 hours increases the risk of a heart attack by 45%. 
There is evidence available that suggests a lack of sleep can exacerbate feelings of anxiety and distress within healthy adults when compared to getting a normal night's sleep.  
It is a complex mechanism, but it's when we experience REM (Rapid Eye Movement) sleep that our body can help recover and enhance brain function, REM sleep also helps with our emotional health.
Scientists do not know the exact processes, but they do know that disrupted sleep, and not achieving REM sleep, affects our hormones and neurotransmitters.
A pattern has been distinguished that shows sleep deprivation increases anxious arousal.
While not absolutely conclusive, it seems that the corticotropin-releasing hormone system and the locus ceruleus-autonomic nervous system are vulnerable to prolonged exposure to stress which can then lead to this dysfunctional arousal state. 
This can have a negative impact on our physiological health. 
Not everyone has the same symptoms or feelings when they are depressed. It is a hidden illness that affects many and has contributed to the premature ending of people's lives.
Statistics published in 2016 reported that nearly 4% of people in England suffer from depression. 
While in the USA, it is reported that 6.7% of the population suffers from Major Depressive Disorder (MDD) with 1.5% of the population experiencing Persistent Depressive Disorder (PDD). PDD is when someone suffers from a form of depression for more than 2 years.
These sorts of figures are similar across the world with depression being listed as the leading cause of disability. It can affect anyone, from anywhere regardless of background, gender or wealth. 
Depression effects people in different ways but it often associated with anxiety. It can manifest itself as feeling low, stressed, hopeless, lacking motivation and even suicidal. 
Clinical reports state that children who suffer from poor sleep have a significantly higher chance of suffering from depression, and a high proportion of teenagers who also have trouble sleeping suffer from moderate to severe depression. 
Studies involving adults have found that sleep difficulties are present in 75% of patients that are depressed, therefore, it is clear that there is a strong link. 
This link is cemented more so with the results of a UK population sample which discovered that 83% of depressed patients had at least one insomnia symptom. 
The immune system helps combat and protect your body from infection. It consists of a complex network of cells and proteins that act like a military force to ensure that you can operate normally. It is also able to keep a record of every germ that has been defeated so it can quickly destroy it again. 
An immune system that is not functioning correctly can make the person more vulnerable to infections, this can be life-threatening. Therefore, you want to ensure that you give your body the best environment to operate as effectively as possible.
Adequate sleep, can contribute towards a healthy immune system as discovered by German scientists that released their findings in the Journal of Experimental Medicine. 
They surmise that sleep helps the immune cells to attach to their target cells infected with a virus to kill it.
How does a lack of sleep affect the immune system?
Research dictates that long periods of sleep loss cause profound stress and increases inflammation activity. 
It is believed that sleep disturbance alters the secretion of nocturnal pro-inflammatory cytokines (signaling proteins) which correlate with immune dysfunction. 
To emphasize the point, scientists from the University of Washington Health Sciences department studied the effects of sleep deprivation and the immune system on a group of identical twins.
The blood samples demonstrated that the twin with a shorter sleep duration had a suppressed immune system compared to their sibling who would sleep 7 or more hours every 24. 
It was commented by Dr. Sina Gharib that “...chronic short sleep shuts down programs involved in the immune response of circulating white blood cells...”. 
These comments are also supported by various experiments that show wakefulness is associated with a high level of inflammatory activity. 
It seems that there is a strong link between disrupted sleep patterns and an increased risk of cancer.
However, a widespread meta-analysis of numerous studies that have investigated the relationship between sleep duration and cancer are not absolutely consistent and warrant further study. 
This isn't to say that there isn't a risk.
While the analysis of many different studies may not conclude a firm consistency of results, there is evidence from studies over a long duration that does connect issues with sleeping and cancer.
For instance, published findings from the American Journal of Respiratory and Critical Care Medicine shows that data from a 22-year follow-up report associates sleep-disordered breathing with cancer mortality. 
Clinical studies do note that night workers face nocturnal melatonin suppression and sleep disturbances that can increase the rise of cancer-stimulatory cytokines which in turn increases their risk of developing different cancers.
Furthermore, there is evidence of melatonin possessing anti-cancer effects as it exhibits cytotoxic activity in cancer cells, therefore, destroying the cancer cell. 
The relevance being, melatonin is a naturally occurring hormone that is released by the pineal gland that controls sleep cycles and is released around the night-time hours in periods of darkness. 
As such, the result of these studies suggest that there is a real need for high quality and undisturbed sleep within uninterrupted darkness to maintain a healthy circadian rhythm. 
And, for good reason, too.
A disruption of the circadian rhythm is connected to an acceleration of tumor growth as outlined in a review of the available literature which was published in the Nature and Science of Sleep journal of 2017. 
There is strong evidence which has been identified by the World Health Organization that “...poor sleep is associated with excess mortality and cardiovascular disease...” 
However, the World Health Organization is not alone in the observation.
This statement and theory is backed up by countless other authorities in the health sphere around the globe such as the National Health Service of the United Kingdom who reviewed the claims from 16 identified studies that involved over 1.3 million adults from over 8 countries. 
Numerous professionals across an international collection of universities observe that insufficient sleep causes a variety of medical and mental dysfunctions that has become a public health concern and is linked to half of the causing cases of death within the USA alone with direct links between inadequate sleep and negative outcomes. 
This will come as no surprise after learning that sleep deprivation is connected with many major health issues which are the leading causes of death including cancer, heart disease, stroke, diabetes, and accidents. 
It has been documented in the journal for European Sleep Research Society that individuals who sleep for less than an average of 7 hours per night are at a higher risk of adverse health conditions and sleep duration is now an important determinant of health. 
Reasons For Sleep Deprivation
There are many reasons for sleep deprivation and disturbance. Some can be controlled and are an active consequence of chosen behavior, whereas others cannot, or some are environmental.
We have listed the reasons below that could be the cause of someone not getting an adequate 7 to 8 hours of sleep per day as stipulated by the Better Health Channel from the Victorian State Government in Australia. 
Whilst at work you may long for your bed and to be at home resting, yet once home you find more stimulating activities that keep you awake for longer.
It isn't uncommon for people to be in a role that doesn't interest them which can absorb the majority of their waking life, so why would you want to shorten your waking hours by not fulfilling your own interests?
The odd late night staying up late watching a box-set, reading, playing video games, or socializing can be recovered by sleeping for longer the next evening (sleep debt), but continued poor sleep can have detrimental effects on your health as we have already detailed.
It is also common for people to go to bed at a reasonable hour yet then stay up staring at the screen on a tablet or phone.
However, this artificial light can cause our internal clock to be confused, upset the circadian rhythm due to the way cells in our eyes process ambient light. Which results in disrupted sleep. 
Pre-existing Health Conditions
We have spoken before about the 'chicken or egg' scenario in respect of health conditions and sleep disruption.
There is plenty of evidence detailing that pre-existing conditions such as obesity contribute to sleep loss and that sleep loss can contribute to illnesses and diseases ranging from the common cold to heart disease.  
If you work night shifts, or long hours, or even staggered shifts that airline workers may experience, and if the statistics are correct, approximately 20% of industrialized society do, you are likely to suffer from sleep disruption.
It is well documented that shift work patterns have a profound negative effect on sleep. Particularly sleep duration which is reported to be up to 4 hours less when sleeping during the day than it is at night.
Similar values are also reported for those on shift rotations, albeit those workers suffer slightly more than those who work permanent night shifts. 
Pre-existing Sleep Disorder
If you have a sleeping disorder such as apnoea, restless leg, or periodic limb movement syndrome during rapid eye movement (REM) sleep this can cause disruption and disturbance which may also promote daytime sleepiness. 
There are many drugs that may be prescribed to a person for medical conditions that may affect their sleeping routine and rhythm.
In addition, some medications which are prescribed to treat other issues may also induce sleep disorders such as insomnia, nightmares, and restless leg syndrome to mention just a few. 
It has already been mentioned that melatonin, the hormone that is released to support sleep is released during hours of darkness, therefore, it is ideal to create a dark environment to sleep in.
However, this can be particularly difficult for those who work night shifts as sunlight can brighten rooms, then there's also the higher chance of ambient noise, there have even been studies into hospital induced insomnia and other sleeping disturbances particularly from lighting and noises. 
Even during normal and healthy sleeping patterns, a partner may snore or you may suffer from noisy neighbors which can cause anxiety, distress, and disturb sleep.
This could tie up with behavior, however, if you go to bed and then start to smoke (stimulates the adrenal glands), drink caffeinated beverages, or engage in stimulating activities such as exercise can make it more difficult to get to sleep.  
Parents of young children will no-doubt understand what sleep deprivation is. It has been recognized that a person going through pregnancy and postpartum periods are susceptible to mood swings which can include depression and psychosis.
There's also significant evidence that links sleep disruption to psychiatric disorders and broken sleep duration is evident in pregnancy and after delivery, the disruption continues even if the child is sleeping in another room. 
Military Sleep Studies
With all of these points highlighted and addressed it would come of no surprise to learn that military personnel will be subject to broken sleep and short sleep duration at some point within their career.
This is because being in the military is more of a lifestyle than a regular job.
There are few corporate jobs whereby you will be faced with continuous hostile operations for 12 months or more enduring physical and mental challenges dependant on the environment or enemy forces.
This can result in difficulties sleeping and disrupting the circadian rhythm which can then onset cardiovascular, metabolic, skeletal, and cognitive ill-health. 
Furthermore, experiences from operations may result in post-traumatic stress disorder (PTSD) or injuries sustained from enemy forces.
While it is often noted that soldiers can sleep in unforgiving environments, being unable to achieve healthy and restorative sleep in the long-term can lead to further impairments and poor lifestyle choices that can exacerbate existing health conditions or trigger new ones such as substance abuse or mood disorders.  
Are Sleep Disorders Prevalent in the Military?
A study investigating the impacts of short sleep duration found that it was common for deployed soldiers from Operation Iraqi Freedom to suffer from sleep disruption.
The figures of nearly 3000 troops suggested that nearly three quarters slept for less than 6 hours per night upon returning from combat operations and this inadequate levels of sleep were also associated with symptoms of depression, panic syndrome, substance abuse, and even attempts of suicide. 
This set of data is also supported by a further study published in 2013 that also demonstrates widespread sleep disorders throughout all three arms of the military, figures that also include personnel who haven't been operationally deployed as well as previously deployed and redeployed. 
Insufficient sleep persists with military personnel that isn't seen throughout the civilian population. 
What does this mean for soldier performance?
Traditionally, soldiers and service members have tried to manage sleep like physical fitness. In that their body can adapt and improve with more training and exposure, however, there is a large body of evidence that contradicts this belief. 
People need 7-8 hours of sleep for each day, preferably during the night as sleep during the day doesn't offer as much recuperation. Furthermore, a period of 30 minutes after waking up makes you feel sluggish, as such, you will not be at your peak performance to carry out tasks.
It has been noted that during operations, without effective sleep management in place, sleep debt can accumulate and this will have a negative effect on a soldier's performance across all parameters, this can adversely affect the mission through errors, poor motivation, reduced alertness and attention with a reduction of physical performance. 
Reduction of complex tasks
Research states that complex mental functions are degraded by up to 25% for every additional 24 hours awake. Sleep deprivation degrades planning, the ability to adapt to changing situations, and understand what is happening. A good example of this was a test to study the accuracy of sleep-deprived soldiers on a shooting range.
Even at 90 hours without sleep, they could shoot accurately at fixed targets, however, as soon as the targets were presented in a more complex manner, such as moving or flipping up in random locations, the soldier's ability to assess and respond dropped significantly.
Now, consider his in a war zone with ever-changing environments with threats to encounter and eliminate.
Blue on Blue
Fortunately, or unfortunately, however, you may wish to position it, this has happened and is documented in war scenarios.
During the ground war of Desert Storm, and after 48 hours of continuous operations, a platoon of 6 American fighting vehicles unexpectedly engaged with Iraqi armored personnel carriers.
The result of the engagement was that all of the Iraqi forces were destroyed. However, 2 American vehicles were also destroyed, minus American casualties.
The following engagement debriefs discovered that the 2 destroyed American vehicles were the result of friendly fire.
This was because although the troops could see and engage vehicles effectively, they had struggled with understanding, grasping their positions, and orientating themselves effectively.
The basic grasp of the task remained, as did their ability to fight. However, they lost their ability to assess and respond to the changing situation, or even what their own position was in relation to friendly forces. 
Many high profile and dangerous missions are conducted by US and Allied forces during the night.
This makes sense, night time and dawn raids can catch the enemy when they least expect it or are simply asleep and has been favored by the CIA, Green Berets, Navy SEALS, Marines and other elite units. 
However, they are not without heightened risk.
While there has been a success with regards to nighttime raids in capturing or eliminating high profile targets which are often hailed by the Western media, there's also been a lot of failures.
One particular mission that became thwarted by a number of errors, was 'Operation Eagle Claw'.
A hugely complex rescue mission spread over 2 nights which included landing aircraft in blacked-out conditions using makeshift infrared landing lights, flying through adverse weather conditions combined with mechanical failures which lead to the disorientation of helicopters which ended up flying in scattered formations eventually resulting in crashes, deaths and losses of military equipment to the Iranian forces.
It has been commented that flawed planning and command structure, pilot training, and conditions all attributed to the mission failure. 
Therefore, it can be speculated, that extensive training, lack of adequate sleep, exhaustion, a disrupted circadian rhythm, and confusion exacerbated by night time operations all contributed to the failure.
After all, any military force that has the capability to operate overseas will have a structured command which will be gathering intelligence and relaying orders throughout different time zones, amongst various networks, and around the clock.
This tempo of operation and communication leads to fragmented sleep for all involved, this can be at command level who need to make the right decisions and down to the operator who is faced with ever-changing circumstances in hostile and highly stressful environments whilst they are relying on their cognitive abilities.
All of these scenarios place additional strain on mental and physical abilities, resulting in detrimental effects that can compromise missions. 
The benefits of night-time operations are accepted as a way to operate under the cover of darkness whilst adding the element of surprise, and, have been employed effectively using the Royal Marines' offensive on Argentine positions in the Falklands War for example. However, it is observed that night time operations strain the ability to maintain control and the effective command of forces. 
A further study looking in to sleep shift patterns of crew members of a US Naval vessel on a rotating 5 hours on and 10 hours off schedule.
The results were that the crew accumulated large sleep debts sustained long periods of wakefulness and showed significant degradation of mood with excessive fatigue which also led to their increased dissatisfaction of the working schedule. 
Additional studies into watchstanding on Naval ships also saw that sleep opportunities are restricted to 6.5 hours for every 24 hours, the results of the study showed extreme levels of fatigue and a reduction of psychomotor vigilance due to the consistent build-up of sleep loss. 
These results were also confounded by the assessment of long term partial sleep deprivation on the abilities of naval officers.
This research found that a lack of sleep significantly impacted an officer's response and foresight into complex problems which had an impact on morale, safety, and the increased chance of errors. 
A survey of U.S Army aviation personnel discovered that many were getting less than 7 hours of sleep per night due to varying schedules that mean many are suffering from fatigue, which can reduce alertness, is related to aviation mishaps, and remains a flight-safety issue. 
As a result, it has been concluded in studies that sleep is critical for operational readiness. 
However, the importance of sleep is often disregarded from the offset of training and during the planning of operations.
And, for quickly escalating operations which then rapidly deploy overseas (such as the Persian Gulf War) into a high tempo regime, the soldiers were deployed at short notice passing through numerous time zones to then commence around the clock operations with immediate effect.
Clearly this rapid movement and change of time zones would have desynchronized their circadian rhythm and had a negative effect on performance. 
Yet, it has been concluded that proper sleep planning and the management of adequate sleep duration can provide a tactical advantage over enemy forces.
By getting the required level of sleep, soldiers can maintain alertness, readiness, and resilience. 
How to get Better Sleep Quality
If you are suffering from an illness or disease which is hampering your ability to get to sleep, you should seek a medical professional.
However, if you merely need a better strategy to get the most from your designated sleeping hours, read on.
These tips are published by the National Heart, Lung and Blood Institute, and the National Health Service of the UK.  
In order to get good, healthy sleep, you need a solid routine. This way it can help your body get into a rhythm of waking and sleeping.
Therefore, set a strict bedtime routine. Make sure you are in bed for a certain time, and, do not get into bed to then start using electronic devices that can absorb your sleep time.
Do not fall foul of setting a strict bedtime regime to then mess around with the actual duration of sleep. Your body prefers a set routine or waking and sleeping hours. Inconsistency doesn't breed effective results.
Adults require 7 to 8 hours of continuous sleep every day.
We have already discussed the effects of too little sleep and its negative implications, but studies also warn about getting too much sleep as well. Sleep duration of 9 hours or more also has negative effects. 
Therefore, stick to the aim of 8 hours. Go to bed at the same time and wake at the same time every day. This minimal disruption will help.
It is imperative that you do not go to bed feeling charged and ready to go on a mission.
You want to ensure that bedtimes are relaxing, your mind is switched off and your body is ready to relax.
If you find relaxing difficult to do, try a few of these techniques:
If you have a busy mind and schedule, try making a list of everything you need to do the following day so you're not constantly thinking about planning or forgetting ideas.
Try slow and gentle exercises such as yoga, do not do exhaustive exercise unless it is much earlier than your bedtime.
Reading a book can help you nod off and distract the mind form previous events during the day or upcoming events.
Calming music can help relax your mind and reduce your tempo.
Avoid the use of electronic devices such as laptops, tablets or phones. These devices emit blue light that which can have an adverse effect on sleep. 
There's no point trying to embrace a new regime and strict timetable if once you get to your bedroom and it isn't providing the optimum conditions to sleep.
The bedroom should be used purely for sleep, relaxation, and sexual activity, it is not a place for work or even exercise.
Here are some tips to ensure it is a welcoming place:
- Ensure you can block out as much external light as possible with thick curtains and blinds
- Try to reduce external noise as much as possible. You can even resort to low-cost earplugs if necessary.
- Remove electronic devices from the room, such as TV's and laptops. If you have to have them in the room, ensure they are turned off at the mains to avoid the standby light disturbing you, place your phone on silent and face the screen down so the light doesn't disturb you.
- Avoid vibrant wall colors or busy patterns. Ensure your environment has a soothing effect.
- Try to maintain a steady and comfortable temperature between 18C and 24C.
- Pets may be comforting, but they may disturb your sleep, if they do, relocate them into another room or level of the property.
- Ensure that your bed is comfortable, not too old, and experiment with pillows.
Physical exercise is important for your health.
There are close links between physical activity being an important factor in preventing non-communicable diseases such as obesity and cardiovascular health but also age-related degradation diseases such as Alzheimer's along with dementia. 
Exercise has also proven to improve mental health and can improve the overall quality of life and health across many parameters. 
Therefore, physical exercise is encouraged on a daily basis, as it can relieve stress, reduce tension, anxiety, and depressed feelings.
Exercise also releases endorphins that can contribute to the feeling of happiness.
One note on exercise, do not exercise too close to your bedtime as it can help stimulate the body and make you feel energized, so ensure any exercise is completed a few hours prior.
Do not drink caffeinated beverages or foods too close to your bedtime as this can disrupt your efforts, it can also reduce your deep sleep that is required to recharge.
Be aware that some foods contain caffeine that you may not be aware of, such as chocolate.
Smoking cigarettes near to bedtime isn't ideal either as nicotine is a stimulant. Clinical research has demonstrated that those who smoke are subject to more sleep disturbance and find it harder to nod off. 
Some recreational drugs can also keep you awake for long periods which will disrupt your sleeping pattern, even if taken just 1 day per week, typically weekends.
While drinking alcohol may make you feel sleepy, it can prevent your body from getting restful and quality sleep. 
Sometimes it can also easy to forget what effect some mixers will have, obviously cola and energy drinks that are popular with vodka contain caffeine.
Drinking high volumes of alcoholic beverages such as beer can also contribute to waking up during your sleep to urinate more regularly.
A published study has concluded that eating food close to your bedtime can have a negative effect on sleep quality, as a result, it should be avoided to optimize sleep. 
Overall, we can see there are many factors that can affect your ability to get to sleep and maintain long sleep duration, many people may fall foul to one or two of those listed.
Nutrition and Sleep
It is not entirely clear if any particular diet does affect sleep quality and duration. Research dictates that while there aren't any firm conclusions without further investigation, it does appear that promising results stem from what is generally accepted as a healthy diet; therefore the inclusion of whole grains for fiber increased fruit and vegetable intake as well as the intake of oils that are low in saturates. 
However, there is evidence that kiwi fruits and tart cherries can promote sleep.
The humble kiwi fruit has a high nutritional value, it contains many different vitamins such as K, A, and C plus minerals like iron and zinc.
It is also high in antioxidants which can help inhibit inflammation and have shown to provide beneficial changes to biomarkers of cardiovascular disease. 
These useful compounds have been identified in the kiwi fruit as being potentially beneficial towards the treatment of sleep disorders as hypothesized by scientists as they saw that the consumption of kiwi fruit improved multiple sleep parameters.
Their research discovered that 2 kiwi fruits 1 hour prior to bedtime helped sleep. 
Like kiwi fruits, tart cherries are able to reduce oxidative stress and inflammation while promoting health.
Tart cherries also include concentrations of melatonin which are linked to the regulation of sleep. 
The beneficial effects of both sleep quality and quantity were detected for patients suffering from insomnia. 
Vitamins and Minerals
Scientific research has also uncovered nutrient extracts from plants, vitamins, and minerals that can aid sleep.
These nutrients can usually be bought individually or may be part of a product, such as Military Muscle.
Let's take a look at a few.
Data strongly suggests that there is a link between vitamin D deficiency and sleep disorders. 
Vitamin D can be ingested through diet, or from ultraviolet-B-radiation predominantly from the sun.
However, it is reported that approximately 1 billion people around the world have a deficiency, as a result, some government bodies such as Public Health England recommend that people take a vitamin D supplement.  
Much of the concern regarding drugs to assist with sleep are the unwanted side effects.
However, research has concluded that 600mg of ashwagandha daily has sleep-inducing potential without any unwanted side effects.
The results of a study saw that ashwagandha improved all sleep parameters when trialed over a 10 week period. 
Mucuna Pruriens (Velvet Bean)
There is evidence that points at mucuna pruriens benefiting sleep, it is thought that the L-DOPA within mucuna pruriens stimulates growth hormone secretion in humans. The tests saw that after 2 hours of ingestion there was a significant rise in growth hormone levels.
Growth hormone is closely related to slow-wave sleep and it is considered this is why it improves sleep quality as growth hormone has demonstrated that it increases sleepiness when it has been injected into human and animal subjects. 
A deficiency in iron is considered to be one of the most popular forms of malnutrition in the modern world. It has been assessed that 50% of the anemia is due to iron deficiency. 
Clinical research has found that iron deficiency negatively affects sleep quality. 
It has been published in the International Journal of Molecular Science that zinc is involved in the regulation of sleep.
Research conducted saw that zinc administration improved sleep quality and quantity of hours. 
While not directly associated with being a sleep aid, Urtica diocia (or stinging nettle extract as it is more commonly known) has been shown to reduce muscle pain effectively, there has also been evidence of reducing inflammation and improving sleep while having no serious side effects. 
There's some limited evidence that outlines the benefits of ensuring we get enough magnesium in our diet to help with sleeping.
One issue is that a typical Western diet lacks substantial leafy greens, legumes, seeds, and nuts like some other parts of the world, and this can contribute towards a deficiency. 
Micronutrient and Sleep Overview
We should not ever be low on micronutrient status and suffer from a deficiency, it can have negative implications for multiple factors of our health and well-being.
However, with many 'fast' and convenient foods options available that are easy to turn to in a modern society that also favors the provision of longer working hours alongside entertainment and consumerism. 
The issue with fast foods is that it typically lacks micronutrient density, particularly lacking in zinc and iron plus vitamin A,C as well as E. 
Findings from data published by the National Center for Health Statistics show that over 36% of adults in the USA eat fast food every day. Furthermore, there was a positive correlation between increased family income and fast food consumption. 
There are emerging studies that are finding a positive relationship between vitamins and minerals with sleep. There is a particularly strong correlation between iron and zinc status. 
Interestingly, we covered these nutrients in our article regarding nutrition for military personnel.
What have we learned from this investigative article?
It is clear from the research that a lack of sleep holds a major detrimental impact on persons health.
It can have an influence and exacerbate any pre-existing illnesses or contribute to further ill-health.
Data states that 80 million US citizens suffer from sleep disorders and that many people get 6 hours or less sleep for every 24, which is less than the recommended 7 to 8 hours that your body requires.
This sleep deficiency is dangerous, it has physical, mental, and hidden physiological complications such as diabetes and cancers.
Research dictates fatigue can be the driver of accidents, poor judgment, and reduced effectiveness – all of which can have a consequence on life.
The military has a complex relationship with sleep.
There is an ingrained philosophy that a soldier can be trained to survive and react from little sleep, as, in a war zone, that is the likely scenario.
However, the studies suggest, unlike exercise, the body cannot be conditioned to work more effectively by reducing sleeping hours during training like it can be when additional physical stresses are placed on the musculature.
And, the results of this sleep deprivation have manifested in disorientation, the inability to judge and perform complex tasks which have ultimately resulted in damage, blue on blue friendly fire and a host of physiological issues for soldiers or veterans.
These effects have been acknowledged and it has been accepted through various studies that adequate sleep will improve military readiness and effectiveness on the battlefield.
However, there are still cultural hurdles to be breached.
In addition, we have discussed different methods of helping people get to sleep sooner and sleep for longer.
These methods include environment, discipline, routine, exercise, and timings.
We also looked at nutrition and micronutrients that can be beneficial, more so considering the high consumption of nutritionally weak convenience food throughout the US and other regions.
While we (science) do not know the exact details as to why sleep is so important to us, what we do know is that a continued amount of sleep deprivation can lead to disease, mental inefficiency, fatigue, accidents, and mortality.
We also know of ways in which to help reach the required 7 to 8 hours of sleep for every 24 hours, science has proven to us that we are far more efficient and capable if we extend our sleeping duration, in many cases, by just an hour longer per night.