07 Dec 2017


The value of sleep, rest and recovery cannot be overestimated and, as Dr Dorian Dugmore explains, burning the candle at both ends can have wide-ranging consequences, some of them highly dangerous.

When you fall asleep unintentionally it’s often your body’s way of telling you to recharge, and many of us will find ourselves rocked to sleep by the motion of a train or while watching TV. Falling asleep in other situations, meanwhile, can be more embarrassing, such as in a meeting or during a presentation. There is the potential, however, for tiredness to put your life and those of others at serious risk, the most common being falling asleep at the wheel.

Reports suggest that up to 40 per cent of us have momentarily fallen asleep at the wheel, while up to 60 per cent of drivers admit to feeling drowsy when driving.

Reasons that you might do this include the mesmerising effect of white noise from the tyres repeatedly drumming on the road and the pure boredom that comes from staring ahead at the open road with little stimulation. However, the principle cause is sleep deprivation and the way that it interferes with the body’s natural biorhythms.

Most accidents behind the wheel occur between 12 midnight and 8am, during which time the body is normally asleep, so its biorhythms change to accommodate that. The body is also light sensitive, so darkness will accelerate the feeling of needing to sleep.

During sleep, you go through three phases: light sleep, when your body starts to relax (30mins), delta sleep, when your body and cells repair themselves (60mins or more) and REM or dream sleep (30mins or more). As you approach waking up time, when rising cortisol levels rouse you, you get more REM sleep and so are likely to dream more.

Your body needs five or six cycles of delta and REM sleep to recover fully, which is why you need seven-to-eight hours’ sleep in total. Compromise on this and it’s likely that you’ll feel drowsy the next day and so will be more prone to falling asleep unintentionally.


To minimise the risk of this highly dangerous event, make sure you get a good night’s sleep the night before any long journey, and always try to get at least seven hours’ sleep.

If you do feel tired, take a 20-minute cat nap before you set off on your journey. Any longer than this, though, and you may move into deeper delta sleep and so feel very groggy.

Avoid alcohol the night before a planned journey, as it accelerates drowsiness, and eat healthy meals full of complex carbohydrates, such as grains, fruits and vegetables. Snack on almonds and walnuts during your drive rather than sweets and chocolates, as sugar causes highs and lows in energy and often accelerates drowsiness.

Taking vitamins (especially vitamin C and B complex) with food rather than on their own will also help you to stay energised, as they are absorbed by the gut better.

It’s a good idea to get out of the vehicle at regular intervals on a long drive, as blood pooling in the legs can occur, reducing the supply of oxygen to the brain, which makes you feel sluggish and lacking in energy. It’s also important to stay hydrated with water during the drive, as even mild dehydration causes a drop of 20 per cent in mental clarity and energy.

If you do find yourself beginning to feel drowsy, it’s essential that you pull over at the first available opportunity. Drink a cup of coffee and have a 20-minute cat nap; while you will be a little groggy for around 15 minutes, you should feel better afterwards.

If you aren’t able to pull over straight away, try pinching your ear or your arm repeatedly to cause yourself some sensory discomfort or play some lively or high energy music until it’s safe to stop.

Signs that you need to pull over immediately include difficulty focusing, frequent blinking, heavy eyelids, daydreaming, trouble remembering the last few miles and road signs, difficulty keeping your head up, drifting from your lane, tailgating and becoming irritable.

When you recognise any of these signs it’s time to pull over, take a nap and have a coffee or, better still, cut short your journey and call it a day. Otherwise, it isn’t only your life that’s at risk, but those of many others too.