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Fatigue can affect us all, and it’s not just a matter of not getting enough sleep.

There are actually three types of fatigue: transient, cumulative, and circadian:

  • Transient fatigue is an acute form of fatigue brought on by extreme sleep restriction or extended periods without sleep over 1 or 2 days.
  • Cumulative fatigue is fatigue which is brought on by repeated episodes of sleep restriction – maybe more mild or extended hours of being awake over a series of days.
  • Circadian fatigue refers to the reduced performance during the night-time hours, particularly during our “window of circadian low” (WOCL) (which is the time our bodies are programmed to sleep, when everything slows down – this is usually between the hours 2am-6am).

Research shows we take time to recover from an accumulation of sleeplessness. Something to bear in mind is that a "sleep deficit" can take many days to recover from, rather than just one good night’s sleep.

Being tired can affect us is many ways such as decreased reaction time, reduced attentiveness or ability to focus, impaired memory and a sense of withdrawn or low mood. Getting enough sleep is essential to functioning well and feeling our best.

Sleep Hygiene Tips

Avoid caffeine, which is a brain stimulant. Having caffeine after 3pm can make it harder to sleep at night. Switch off mobile phones, computers and TVs at night. If possible, keep these out of the bedroom altogether – there is much researched evidence which demonstrates that Wi-Fi stimulates brain activity, which can contribute to not sleeping. Also playing games and chatting online eats into sleep time, making it hard to function the next day.

Sleeping during the day can make it harder to get to sleep at night. Keep naps to 20 minutes, and don’t nap too close to bedtime. Try going for a walk instead.

Try to make the hour before bedtime calm and relaxing. Avoid exciting or upsetting activities, such as electronic games and TV. A regular bedtime is best and sleep is best in bed, not on the sofa or in a comfy chair.

Try to encourage good sleep habits and daily physical activity. Teenagers need about 9¼ hours of sleep each night and at least 60 minutes of physical activity every day. Looking at ‘Sleep Hygiene’ is very popular at the moment. The National Sleep Foundation have some useful information on this, you can access their website HERE

Also, click HERE for the TED link from Professor Russell Foster (Chair of Circadian Neuroscience - Brasenose College Oxford) which is interesting.