Naps are pretty great. Clonking out after a massive meal. Passing out in the sunshine. Cozying up in bed in the afternoon when we’re sick. Spending the entirety of your hangover day in and out of consciousness in front of Netflix… Nothing quite beats a good nap!
Except for a good night’s sleep, of course.
But Albert Einstein used to sleep in 30-minute spurts, and he was a genius! So why can’t we? Why are the experts saying that we can’t replace sleep with naps?
The 8-hour Sleep Cycle: Why do we Sleep?
While we’re asleep, our body and mind go through some vital repair and memory storage processes. Our short-term memory gets processed as long-term memory. Our muscles repair themselves, and while we’re asleep, we grow and develop. Our hormones regulate, our cognitive function improves, and so so so much more!
A lot of these processes only take place at certain stages of sleep. There are 4 main stages of sleep that we need to go through multiple times in order for our body and mind to stay happy and healthy.
NREM 1 is Stage 1 of our Sleep Cycle.
In this sleep stage, otherwise known as light sleep, our metabolism slows down, our muscles relax, eye movement slows down, and brain wave activity dips. This sleep stage actually facilitates new ideas. This is the easiest sleep stage to wake someone up from.
NREM 2 is Stage 2 of our Sleep Cycle.
In this sleep stage, activity in the body and brain decreases. Eye movement comes to a halt, brain waves slow down, muscles relax, your body temperature lowers, and the heart rate decreases. We spend between 40%-60% of our sleep cycle in this stage, just before we head into it.
NREM 3, Stage 3 of our Sleep Cycle.
This is our deep sleep stage. Deep sleep is the most beneficial stage of our sleep cycle, as this is where we benefit from our sleep’s restorative properties. Our muscles are nice and relaxed, our brain waves are slow, and it’s the deepest stage of sleep before REM sleep.
On average, we spend about 5%-15% of our sleep cycle in this stage. Relative to how much time we spend in other sleep stages, we spend a relatively short amount of time in NREM 3; however, it seems to be the stage of sleep that yields the greatest effect on our bodies.
If during a nap we reach NREM 3, we’re likely going to struggle to get to sleep that night, as our brain and body have already had a chance to restore themselves.
After NREM 3, we head into…
REM Sleep, our 4th, and final sleep stage.
Rapid Eye Movement sleep causes rapid side-to-side eye movements, quick, shallow breathing, an increase in heart rate, and an increase in blood pressure. Our bodies lose control over body temperature regulation during this sleep stage. REM sleep is when we dream, often very vivid dreams.
While it’s easy to wake someone up from REM sleep, it’s best to avoid it, as waking up before finishing our REM sleep can result in that groggy feeling which can last from minutes to hours.
How long does it take to get through all of the sleep stages?
It takes on average 1.5 hours to get through all 4 sleep stages.
Ideally, we should go through 5 cycles of our 4 sleep stages each night.
This means that ideally, we need to be allocating around 7.5 hours (1.5h for all sleep stages x 5 sleep cycles) of sleep per night to our sleep routine in order to cycle through all 4 sleep stages enough times to benefit from sleeps restorative qualities.
So what’s wrong with napping?
Nothing, really! In fact, if our body or mind needs to recover, we might need more sleep than usual, making naps pretty ideal!
The PROBLEM with napping only arises when we rely on napping to make up for not enough sleep at night.
Making up for lost sleep
According to neuroscientist and sleep expert Matthew Walker, we can’t simply make up for lost sleep by napping the following day.
In an interview with Joe Rogan back in 2018, Matthew says, “Naps can actually give you benefits; we’ve done some of these studies where they improve your learning, your memory, your alertness, your concentration, especially your emotional regulation too. Sleep is critical for emotional first aid and mental health; however, you can’t keep using naps to self-medicate short sleep of 4 or 5 hours each night.
We know that the system itself, your brain has no capacity to regain all of the sleep that it’s lost. It will try to sleep back some of that debt, but what we’ve discovered, let’s say I take you tonight, I deprive you of sleep, 8 hours lost, then I give you all of the recovery sleep that second, third or fourth night. You will sleep longer, but you will only get back maybe just 3 or 4 hours of that lost total 8, so sleep is not like the bank. You can’t accumulate a debt and then try to pay it off at the weekend. There is no credit system in the brain for sleep. You can’t bank it.”
Each time we cycle through our 4 stages of sleep, the body and brain benefit from them in succession. There’s a reason why it’s more beneficial for our health and wellness to get those sleep cycles one after the other, rather than not running through enough cycles at night and then trying to make up for it the next day by napping. As Matthew Walker explains, unfortunately, napping and our sleep does not work like that. We can’t make up for our lost sleep with a nap.
So I shouldn’t nap?
Now, this doesn’t mean that you shouldn’t nap after a bad or short night’s sleep. Making back some of our sleep is better than making back none of it!
However, if you are relying on your naps rather than working towards fixing your sleep routine to aim for 8 consecutive hours per night, this could be worth changing.
Napping can be great for you, especially when you’re sleep-deprived or recovering from a physical injury or mental trauma. HOWEVER, we cannot rely on napping to make up for lost sleep.
Priority 1: Making sure we are getting our 8 consecutive hours of sleep as often as possible
Priority 2: Enjoy a nap when you’re in recovery mode!
If you’re concerned about your sleeping patterns, there are lots of sleep therapy techniques out there! Be sure to speak with your healthcare provider for advice on improving sleep quality and quantity.