Recently, during an extended stay in Taiwan, I started with floating sessions.
Every other week, I float for about 70 minutes in a tub filled with magnesium-sulfate-saturated water, a so-called flotation tank, also known as an isolation tank.
The water is kept at skin temperature, and the tank is supposed to be sound and light proof. Upon closing the door or lid, it is pitch dark, and you hear almost nothing. Float therapy was original devised to answer the question “what happens to the brain in the absence of sensory stimulation?”
In the meantime, it has become a popular tool to reduce stress, solve creative problems, help with insomnia, and improve performance, among others.
So far, I have done two sessions, with more coming up.
I have found that floating can be very relaxing and uplifting. With this post, I would like to inspire you to try it yourself.
How to prepare for floating?
In my previous post, I explored how day-time noise impairs our cognitive performance and what we can do about it. But there is another big elephant in the room – our night-time sleep. Sleep or the lack of it has a big impact on our ability to perform at our best, both physically and mentally.
Less or disrupted slow-wave sleep, for example, entails poor memory and poor wound healing.
Among the worst offenders interrupting our night-time sleep is the all too familiar sound of SNORING. Snoring can be loud – very loud indeed. A loud snorer can reach more than 90 decibels of peak sound pressure level. That is about as loud as a lawn mower.
Intrigued by the capabilities of some of the newer devices to block out noise and sophisticated white noise apps, I decided to run an experiment to answer this question: What is the best way to block out snoring noise?
Test equipment and candidates
- An iPad equipped with a sound level meter (Noisee for iOS).
- Two different white noise apps: myNoise for iOS and White Noise by Tmsoft for iOS and Android.
- Earplugs of different sizes by Hearos, 3M, and Mack with a noise reduction rating (NRR) of 29-33 (an NRR of 33 is about as good as you can get).
- Good-quality earbuds (a good fit is vital for sound quality and noise isolation).
- The best earmuffs I could find, with a noise reduction rating of 31 (3M Peltor X5A).
- DIY noise isolating earbuds and sleep headphones.
- The best noise cancelling headphones I could find (Bose Quiet Comfort QC35).
Testing the snore blocking effectiveness
I have been an afternoon napper for more than 14 years. I started napping after moving to a country where most people took a siesta. For various reasons, I just couldn’t get enough sleep during the night, so it was easy to fall asleep.
Over the years, I have tried short power naps, 60-minute naps, and occasionally 90-minute mid-afternoon sleeps. In this post, I would like to share with you how to nap for better mood, alertness, concentration, improved memory, and restoration of learning capacity. We will cover how long and when to nap for maximum benefit, how to avoid after-nap grogginess (sleep inertia), and the possible risks associated with longer naps.
As a final point, I am going to share my personal napping experience and my favorite napping hacks.
The benefits of napping are numerous
For me personally, the most important benefits are improved mood and decreased sleepiness. I just feel happier and ready to tackle my afternoon after a nap.
Napping studies have found a large number and variety of benefits of napping in all kinds of workplace and operational settings. Studies looked at drivers, commercial airliner pilots, shift workers, doctors and nurses, students, children, senior citizens…
Here is a non-exhaustive list of research-proven benefits:
- Improved cognitive performance
- Increased alertness and concentration
- Decreased reaction time
- Speed and accuracy improvement on cognitive tasks
- Better mood
- Less sleepiness and fatigue
- Significantly reduced number of driving incidents such as drifting out of one’s lane in a car simulator experiment: the number of incidents caused by drivers who had taken a 15-minute coffee nap (see below for details) was 91% less than for drivers who had just taken a break. Coffee alone reduced the number of incidents by 66%.
- In a NASA study, pilots who took naps were able to maintain their performance and reduce incidents during a demanding multi-day schedule. Pilots who weren’t allowed to nap experienced deceasing performance and a significantly larger number of incidents, including during the descent and landing.
- Significantly Improved memory and protection of learned information from interference: a study that focused on declarative learning found a 60% increased memory retention for nappers at a final test one week after initial learning, compared to learners who hadn’t napped.
- Nappers perform better at abstracting general concepts and making connections that weren’t directly learned but can be inferred from what was learned (relational memory).
- A nap can restore the capacity to learn, which otherwise deteriorates considerably with time awake.
- Performance on a creative problem solving task where subjects had to find a linking word between three seemingly unrelated words was improved by more than 40% after a 90-minute nap containing REM sleep (see below) compared to rest and naps containing only non-REM sleep.
To better understand what nap length you should aim for, here is a sleep architecture primer