Some time ago, I wrote about my experiences in changing my sleeping pattern to consist of two sleeping periods per day - a brief, 60-90 minute sleep in the afternoon or evening, followed by a shorter than usual night's sleep.
I found then that after a period of adjusting to the new schedule, during which I was haunted by strange dreams and a sense of jetlag, I felt much more well rested, and could retain my focus much longer - in particular, I found it much easier to wake up early, and the evenings were a buzz of productivity.
Fast forward a couple of years, and I have finally given up on the notion of sleeping twice a day, and I have returned to the "normal" pattern of sleeping a full night, being drowsy in the mornings and afternoon.
But if it worked so well for me, why did I give it up?
In short, changing your sleeping patterns in a non-standard manner is simply not compatible with social life. The experiment was conducted while my life was facing a new direction, and much of my focus suddenly went to my business and myself. In such circumstances, it is much easier to maintain a schedule for these things, but they quickly become restricting once your life opens up to others again. The problem boils down to two things: Social code, and the need for consistency.
Let's start with the social aspect of things: It's just not accepted to take a nap in the western society. Taking a nap in the afternoon or evening, is frowned upon, considered lazy, and has been the target of many humorous cartoons and ridicule over the years. This in spite of research, and my own empirical experience that taking a nap actually makes us more productive, more focused, and possibly even live longer. I remember when I started my career in leadership, workdays would be long and I would steal a fifteen minute nap by turning my back to the door of my office, holding my phone between my head and my shoulder to give the impression that I was in a phone conversation or meeting. As ridiculous as it may seem, this gave me the boost I needed to stay sharp, and was vastly more efficient than coffee. (Of course, actually taking a nap would not have been accepted then any more than it is now)
It also becomes a nuisance when you are making plans. Having to find a place and time to nap before going out to dinner, travelling or visiting friends is not always viable, and trying to hush down your entire family (or building a hiding spot in the boiler room) is just not feasible.
Which brings us to the second breaking point - the need for consistency.
In order for this to work, you can't cheat. When I met my fiancée, I started to spend weekends at her place, and immediately went back to "normal" sleeping patterns once I was with her. I thought to myself that I could keep my rhythm going when I was at my place and revert to normal sleep the odd days I was in her town, but it quickly dawned on me that it was not possible. I would struggle to get back in gear once I got home, and I would lose a couple of days each week to get back in the groove. This gradually got to a point where I just didn't find the effort worthwhile anymore, and promptly went back to regular sleep. (Ironically, feeling much less rested the first morning than in a long time)
Do I miss sleeping twice a day? I do, but I mostly miss the burst of energy I always felt in the evening (after the nap) and in the morning after getting out of bed. To stay alert in the evenings, I have taken to coffee later in the day, but I have found an irritating side effect: It seems that having coffee a bit too late (around the time I usually had my nap) interferes with my night's sleep, causing me to wake up suddenly an hour after going to bed, usually with a nightmare. I'm hoping it will go away, but so far it has been pretty consistent.
There have been some lasting effects of a positive nature, though. I am much more prone to waking early in the morning than I ever was - something that could possibly also be attributed in some extent to me getting older - and I have retained my ability to effortlessly fall asleep quickly when and if I choose to take a nap. When I started experimenting with two-phase sleep, I would struggle to fall asleep in the afternoon, often having vivid (and not always pleasant) dreams, but I eventually learned to fall into a deep sleep almost immediately (usually while thinking "I'm much too awake, how will I ever be able to go to sleep?") and this ability has stayed with me.
So, in the end, not all was lost. And once I hit retirement, you will probably find me sleeping twice a day again - at least.