Sleep 101 - What happens while you sleep

Sleep 101 – What happens while you sleep

Sleep plays a crucial part in maintaining good health, and the effects of sleep deprivation are very real. From memory issues, mood changes, weight gain and weakened immunity, sleep plays a crucial part in helping you to perform better but also to feel happier and healthier.

An article from Feld and Born (2019) highlights the importance of sleep in facilitating memory, particularly in regards to the formation of long-lasting memories. Although many of us know the importance sleep has on our mental and physical wellbeing, have you ever wondered what happens while you sleep? We have developed a short guide to help explain what happens while you sleep.

There are 5 stages of sleep that we typically cycle through during the night, these are:

Stage 1: The transition from wakefulness into light sleep – your body temperature drops and muscles begin to relax.

Stage 2: Heart rate lowers and breathing slows down.

Stage 3 and 4: Blood pressure falls and brain waves slow down. Some research suggests that during this stage your body activates the immune system to protect the body from infection.

REM: Also known as Rapid Eye Movement, dreaming occurs during this stage. REM sleep has been shown to facilitate memory and learning.

Other research supports that stress and reduced sleep in conjunction increase appetite, cravings while also decreasing motivation for physical activity (Geiker et. al. 2017). Something as simple as aiming to have the recommended 7-9 hours of sleep could help reduce cortisol (the stress hormone) levels and make reaching your health and lifestyle goals easier.

How you can get a good night’s rest

There are a few simple tricks you can do to ensure you get the recommended 8 hours of shut-eye each night.

  • Ensure you are in a dark room. Your body naturally produces melatonin in the dark which helps you to fall asleep. If there is light coming in when you are trying to sleep, try using an eye mask.
  • Finish eating a big meal or exercising vigorously at least three hours before you get into bed.
  • Switch off from all technology for at least an hour before bed – that means TV, emails, phones, computers or tablets.
  • Spend at least half an hour before bed doing something you find relaxing – whether it’s reading a book, having a warm bath or listening to some music and spending some time with your other half.

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Feld, G., Born, B., 2017. Sculpting memory during sleep: concurrent consolidation and forgetting. Current Opinion in Neurobiology (44), 20-27.

Geiker, N., Astrup, A., Hjorth, M., Sjödin, A., Pijls, L., Markus, C., 2017. Does stress influence sleep patterns, food intake, weight gain, abdominal obesity and weight loss interventions and vice versa? Etiology and Pathophysiology, Obesity Reviews.