'Sleep' and 'stress' are 2 words that are spoken about a lot this year. The uncertainty, isolation from loved ones and the financial strain for a lot of people has spiked our stress levels, and in turn, this has affected our sleep. Sleep is so important for our day-to-day functioning, our decision making, memory and cognition, and adaptation to stress and change in our lives.
The word 'sleep’ can mean very different things to different people, and what is defined as ‘quality sleep’ can also vary from person to person, due to many varying factors.
But overall, as human beings, we need to sleep.
Sleep is an all-encompassing dynamic process that is essential for human life. During sleep our body restores and recuperates.
Sleep Cycle - Throughout the night, our sleep goes through cycles, ranging from 70-100 minutes in the first cycles of the night, to 90-120 minutes later in the night/early morning.
Sleep Stages – There are 4 sleep stages: one for rapid eye movement (REM) sleep and three that form non-REM (NREM) sleep. Stage 3 and 4 are associated with deeper sleep.
Sleep is involved with the following processes-
- Brain function and repair
- Emotional Regulation
- Weight Maintenance
- Cellular Repair and growth
- Cardiovascular Health
Increased levels of stress in our lives can cause havoc with our sleep.
Stress raises the levels of numerous Hormones which play a vital role in our sleep cycle
Cortisol – Often called the ‘Stress Hormone’ is released by the adrenal glands when the body perceives stress. This can raise our heart rate and blood pressure. This is our body’s natural ‘fight or flight’ response, which has kept humans safe for thousands of years.
Increased levels of stress can mean increased levels of Cortisol being released by the body. In the mornings our Cortisol levels are naturally high to get us up and moving for the day, then they decrease throughout the day to prepare the body for sleep. This is usually when the Hormone Melatonin is released to induce sleep.
When we are stressed, our Cortisol levels can stay high.
Increased levels of Cortisol can have the following effect on our sleep (2):
- Decrease in Slow wave sleep and REM sleep (Stages 3 & 4 of the sleep cycle), so therefore a less restorative sleep.
- Shorter total sleep time
- Shrinkage of the Hippocampal volume suggesting poor emotional memory recall.
- Inhibits the release of other Hormones which are involved in the Sleep-Wake Cycle.
3 Signs that you are too stressed to sleep:
- You can’t ‘Switch off’ your mind
- Muscle Tension
- Increased heart rate
Following good sleep hygiene practices is very important for reducing stress and increasing sleep quality
Having a Night Time Routine to relax the body before sleep can improve your sleep quality and quantity.
- Definition of Sleep – Oxfords English Dictionary, Google – cited 7/10/20
- Sleep, Health & Consciousness – A Physician’s Guide – Reza Samvat and Henry Osiecki, Bio concepts Publishing Australia 2009.