Sound familiar?
Sadly the reality is that it’s all too familiar for most sectors of the maritime industry. Long working hours and adverse environmental characteristics are associated with sleep impairments, and therefore with health and safety risks, including accidents and injuries.
Research shows that those who work more than 33 hours a week report less than 6 hours sleep per day (or night) and poor sleep quality is affected by overtime hours worked, low support and an adverse physical environment.
So what is normal sleep? And how much of the stuff do we really need?
Interestingly, we don’t fully understand what sleep does, but we all know when we need to sleep, we can feel it. We also know when we feel rested and have had enough sleep. We can also switch from a state where we appear unconscious, to being fully aware and carrying out normal activities within a couple of minutes.
Sleep is split into non-rapid eye movement (NREM) and rapid eye movement (REM) phases. REM sleep is when you dream and is very different to NREM sleep, where the size and speed of brain waves generated dictates further stages of sleep.
During REM sleep, you are almost completely paralysed, only your eyes move around, possibly in a pattern relating to the images you see in your dreams. Views are split on which phase provides the deepest sleep; some believe it’s REM as it can be difficult to wake someone, however NREM provides sleep deep enough for your body to restore from the wear and tear of activity when you’re awake.
The function of dreams would be a whole other blog, but it’s important to know that research shows REM deprivation can cause some strange behaviours and impact on many aspects of the body functioning.
So what happens if we don’t get enough sleep? Common symptoms of fatigue include the following and I’m sure we can all recognise times we’ve been affected. For those working at sea, the symptoms of acute fatigue, and chronic (long term) fatigue could be deadly.
- chronic tiredness or sleepiness
- headache
- dizziness
- sore or aching muscles
- muscle weakness
- slowed reflexes and responses
- impaired decision-making and judgement
- moodiness, such as irritability
- impaired hand-to-eye coordination
- appetite loss
- reduced immune system function
- blurry vision
- short-term memory problems
- poor concentration
- hallucinations
- reduced ability to pay attention to the situation at hand
- low motivation.
Working under time pressure, autonomous working, and working with demands on vigilance (as found working on any vessel) can impact on fatigue. These can be partially mediated by fatigue processes and social support is a critical resource to protect against fatigue. However this can be a negative in the maritime industry with ever changing crews.
Longer term, insomnia and chronic fatigue should be considered serious and can contribute to the following:
- Increased risk of mortality is associated with short sleep lengths.
- Insomnia is the best predictor of the future development of depression.
- Increased risk exists of developing anxiety, alcohol and drug use disorders, and nicotine dependence.
- Poor health and decreased activity occur.
- Onset of insomnia in older patients is related to decreased survival.
- Primary insomnia is more common in women than men.
So, it’s very clear that good sleep is vitally important to our health, mental health and wellbeing, and you can develop short and long term health concerns if you’re not getting enough. For those who struggle with sleep, we’re planning a blog all about insomnia and ways to combat it, so watch this space!.
Sleep well!