Fit for Purpose – Sleep

Imagine a pill, like a multivitamin of sorts, that could give you more energy, improve your memory, and was empirically proven to make you more attractive to the other sex. Not only that but lowered your risks of several cancers and of heart attacks. Well, you don’t need to imagine it. And it’s free. It’s called getting enough sleep.

Most people need eight hours of sleep a night (less than one percent of the population can survive on six hours a night), some people may need up to nine hours to feel fully rested. However, many people just aren’t getting enough sleep. Thirty-four percent of Britons are living on between five and six hours of sleep each night. During my first term here I was definitely sleep deprived, as it took me less than five minutes to fall sleep every time I got into bed. This year, I resolved to get sufficient sleep most days of the week, and the difference has been palpable.

Why do we sleep though? In short, we aren’t sure. Sleep does a lot of good things for your body, and is absolutely necessary, but there isn’t a concrete answer as to why. During sleep you alternate between two stages: REM (rapid eye movement) and non-REM. In REM sleep your brain cycles through the things you have been thinking of during the day and tries to make random connections between the things you learnt and other facts that you know. This is the period during which your most vivid dreams occur. In non-REM, or deep sleep, your brain refreshes itself and essentially cleans out the metabolic by-products that build up over the day. Basically, you need both. Each sleep cycle lasts approximately one and a half hours, with the cycles shortening in the early hours of the morning. If you are tired during the day and need to nap, a 20 minute nap will boost energy, while a 1h30 nap will refresh your brain and aid with memory.

Why do we feel tired when we do? There are two systems that work in parallel to regulate your sleep. The first is your circadian rhythm. This is regulated and adjusted by anything from when you exercise and see sunlight, to when you socialise and eat. The other system is sleep pressure, which is a build up of a chemical called adenosine in your brain. This builds up as you are awake, and drops of when you sleep, basically making you more tired as you stay awake for longer.

The reason that we are advised not to use our phones too soon before bed it because blue light indirectly effects our circadian rhythm, delaying at the time that we start to feel tired. The reason that we are advised not to drink coffee too soon before bed (and the reason that it wakes us up when we feel tired) is because caffeine stops us from feeling sleep pressure.

Sufficient sleep is essential to regular functioning, and it is not normal to fall asleep in lectures. During exam term an extra hour of sleep will help you more than an extra hour of revision, and the same is often true in regular term time.

Struggle to fall asleep? Try an army trick for falling asleep (which works for 96% of people within weeks of practicing it). First relax your face, including all muscles around your eyes and your tongue. Then, relax one arm, following the relaxation down from the neck. Then the other arm, the chest, and each leg. Clear you mind and breathe deeply. Imagine yourself either in lying a boat in the middle of a lake or lying in a hammock in a pitch-black room. Works for me, why not give it a go?