It cannot be overstated: getting a good night’s sleep – and getting enough sleep – is vital. In today’s society, sleep is far too often overlooked. Unsurprisingly, the lack of sleep has a huge impact on our lives. Today I’ll explain how sleep is the key to healthy living!

1. Sleep affects our performance

Our performance decreases if we lack sleep

First of all, when we are deprived of sleep, our performance suffers, whether physical or cognitive. An athlete would not run a marathon having slept only 4 hours the night before … So, don’t expect to perform well at work if you’ve only gotten 4 hours of sleep!

Sleep deprivation causes memory and attention problems, and it will be much more difficult for you to make decisions with a lack of sleep.

On the contrary, a good night’s sleep enables us to recover from the day we just spent – and prepares us for the day ahead. If we do not give our bodies time to recuperate, it is impossible to be efficient.

Experiments were carried out on several groups of people for 2 weeks: the first group slept 8 hours per night; the second only slept 6 hours per night, and finally, the last group, only 4 hours per night. The volunteers then had to work on their working memory, that is to say, perform a task that involves learning – and therefore the integration of certain skills in order to be able to perform the task in question.

For the groups having slept 6 hours and 4 hours per night, there is a continuous deterioration in their performance with the task – while the group having slept 8 hours per night becomes increasingly efficient with this same task. The conclusion of this test is that the learning had a beneficial effect only for the group who got 8 hours of sleep. The second group, however, slept 6 hours per night – two hours less – and yet the results obtained were a far cry from those of the first group.

Sleep is vital: it’s a key component of performance and a precondition for intellectual development.

It is hard to make up for a sleep deficit

Lack of sleep has very negative effects on our performance, which is not a surprise.  If you go without enough sleep for consecutive nights, you will have a sleep debt: the equivalent of two weeks in a year for an average person. This means that to catch up on your sleep, you would have to spend two full weeks in bed sleeping.

However, that is not how things work! Do you know how long it takes to make up for a sleep deficit? Do you think that you can actually repay your sleep debt? Yes and no.

  • No: because it is not enough to sleep nine hours one night to make up for the seven hours of sleep the night before.
  • Yes: it is possible to catch up on your “backlog”, but you never truly recover the number of hours lost.

If you have accumulated a large sleep debt, accumulated over several days – or even several weeks – several nights of quality sleep will be necessary to get back to your usual rhythm.

Therefore, in order not to run a deficit, one should get at least 8 hours of sleep per night. In fact, if you sleep 6 hours per night for 14 days in a row, this is tantamount to one sleepless night. Likewise, sleeping 4 hours per night for 14 days is tantamount to 2 sleepless nights.

That said, the best thing to do is not to have a deficit to make up for in the first place!

2. Quality sleep is vital for our capacity to learn

Sleep is vital: how sleeping well is essential for productivity

Sleep primes us for learning

There is a very strong link between sleep and learning. Prior to taking in new knowledge, sleep will prime the brain for learning and provide favorable conditions for it to store new information. All phases of sleep play an important and essential role in learning – so if you lack sleep and don’t sleep through your entire cycle because you went to bed too late or woke up too early – then your brain will not be 100% available to learn effectively.

When we sleep for 8 hours, we go through 3 sleep cycles. Light sleep, deep sleep, then REM sleep. If the quality of our sleep is not optimal during any of these three cycles, it will have negative repercussions on our future learning.

The impact of lack of sleep on memory

Lack of sleep decreases our ability to learn new information. Indeed, as I mentioned at the beginning of this article, sleep not only helps us prepare for the next day, but it also helps us to recover after the day we just spent.

If you try to learn new things while you are tired, you will notice that it will take you a lot longer than if you were fully rested. In addition to this difficulty in learning as effectively, as usual, the memory of what you have acquired will be less precise: This means that you may only remember a small portion of what you have stored.

Try to adopt new habits and get 8 hours of sleep per night for a while – I’m sure you’ll see the effects sooner rather than later. At night, the brain sorts the information integrated during the day and keeps only that which will be useful to it in the future. Test it out: watch a news broadcast or a documentary with a friend. A few weeks later, talk to your friend again about what you saw together and ask them what they took away from it. By doing so, you will see that the information your friend has kept in your memory is not the same as what you have in mind.

Sleep helps sort through all the information and requests you receive on a daily basis, hence the expression “Sleep on it”.

3. Poor sleep affects our mood

Drunk or sleep-deprived?

Sleep deprivation has been shown to have the exact same effects as drinking alcohol. A sleepless night is equivalent to a blood alcohol content of 0.8%. The limit to legally drive is therefore exceeded.

People in sleep debt have a strong tendency to believe that they are less impaired than they really are, just like people who have consumed alcohol. The important thing to remember is that driving while sleep-deprived is as dangerous as driving while intoxicated.

The adverse health effects of not getting enough sleep

Sleep debt decreases both the quality of your work, but also the quality of your family life, and your relationships with others.

This is because sleep deprivation greatly alters mood. In fact, it leads to a lack of motivation and enthusiasm as well as great difficulty in concentrating. It brings out all the negative emotions that are within you. I am sure you have already noticed that when you are tired, you are moody; you become irritable and sensitive very easily. For some, it even goes as far as anger – you get angry very quickly and for no particular reason.

On the other hand, children who lack sleep suffer from impulsivity, hyperactivity, and inattention. Sleep should be taken very seriously from an early age in order to create good habits. Good sleep goes hand in hand with a stable mood and peace of mind.

I hope this article has shown you the importance of a good night’s sleep. Establish new habits. First, start by going to bed 30 minutes earlier. Then gradually increase it to achieve eight hours of sleep per night.


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