8 Hours a night or DIE

Sleep is an incredibly nuanced and largely mysterious activity. We spend roughly a third of our lives asleep and it effects our neurology and physical functions in ways some of which we don't even understand.
It's it's far too complicated a subject to just say that we sleep for this reason or for that reason; even if both are true they do not account for the whole, bigger picture.
A huge amount of research is still to be done and a large part of sleep science remains a mystery even to the top scientists in this area.
However, despite the complicated nature of sleep there is a simple way to sum it up: which is you should sleep for 8 hours every single night and the benefits of doing this will be be credibly vast and will affect all areas of your life including your physical fitness, your intelligence and your health at large.
Some you may be thinking that you don't need 8 hours of sleep and you're fine with 5 or 6. In a majority of cases you would be incorrect and it has been proved in various studies on various things that the vast majority of people need 8 hours of sleep and will suffer negative consequences if they don't.
So my job with this article is to try and convince those of you that think they can function fine from just a couple of hours sleep that they should change their ways...

We don't know our true baseline.

Many people live in a chronically sleep deprived state, the worst thing is that they think that it's normal. They get so used to how they feel from 6 hours of sleep and a lot of caffeine that this becomes their base line. It doesn't have to be this way, you can feel better, look better, be healthier by having more sleep.

You need sleep to learn.

A study was done where 2 groups had to learn a keyboard sequence. One group learnt in the day and was tested 12 hours later at night, the other group learnt in the night and was tested 12 hours later in the morning. So basically both groups had 8 hours in-between learning & testing but only one group slept during that time. Surprise surprise, the group that slept in-between were 20% quicker and 35% more accurate than the other group.

Different parts of sleep are responsible for different things.

A nice follow on point from above, they identified at which part of sleep was stimulating the area of the brain that was responsible for learning these motor skills. They found that this area of the brain was stimulated the most during the 7th and 8th hour of sleep! So you really need that 8 hours! 

8 Hours makes all the difference in elite sport

A study was conducted on NBA players comparing a group who slept for 8 hours a night and a group that slept for under 7 hours a night. The results showed the 8 hours group played for 12% more minutes, 29% increase in points per minute, 2% increase in three-point percentage and 9% increase in free throw percentage. The less than 7 hour group? Well, they had a 37% increase in turnovers and 45% increase in fouls. For those of you unfamiliar with NBA terminology, i'm sure you get the picture - when competing at an elite level you need to get the full 8 hours if you want to get to the top of the foodchain.

Danger of Death

The final point is a more sombre one. This study looked at data from 7000 car crashes in the USA. The study highlights the tragic consequences of not having enough sleep. If you have less than 5 hours sleep you are three times more likely to be involved in a car accident.
If you have had less than 4 hours sleep, you are 11.5 times more likely to be involved in a car accident!! 

Further Reading

Why We Sleep (Book) - Matthew Walker

Buy 'Why We Sleep' now from Amazon! 

The information in this article was largely taken from Matthew Walker who is one of the most famous and pioneering sleep scientists of today. His book is a must read.


The author of this article is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to (“” (, or