I have been tracking my time for the last 19 months. When I ran the calculations on the first 12 months, I discovered I was sleeping 7.4 hours/day. When I ran the calculations for the next 6 months, I discovered I was sleeping…7.4 hours/day. In other words, I am pretty sure this is what my body is aiming for. To be sure, it is often a disjointed 7.4 hours. For the first few months of that, I had a newborn. The newborn turned into a really crappy sleeper. The night before I wrote this post, he got up at 2, and I had trouble getting him back down. At one point, I must have fallen asleep on the bed in his room, because when I woke up at 3:30, he was asleep on the floor in front of the door, thwarted in his escape by the baby lock. I snuck out and left him lying there. I tossed and turned a bit but fell asleep around 4, I think. The good news? He proceeded to sleep until 6:30. Since I had gone to bed around 9:30, I got…around 7.4 hours of sleep. If he had woken up at 5 or 5:30, I probably would have tried to take a nap in the afternoon. Some weeks are better or worse than others, but between naps, trading off with my husband, or going to bed earlier, that's how I wind up arriving at a pretty set number, averaged over the long haul.
I know not everyone can take naps during the day (or has a spouse to trade off with on the kid front). But when I studied the time logs I collected for I Know How She Does It, I saw a fair number of catching up strategies. Someone might turn off an alarm, and accept that a morning workout would not happen (or a first meeting might be taken by phone from the car). People fell asleep in their kids' rooms at night, or on the couch in front of the TV. People slept in on weekends if they had older kids. Such sleep is likely worse quality than a solid 7-8 hours in one's bed nightly, but for people who are not chronic insomniacs,* the catch-up function can be pretty strong.
Here's the tricky part, though: the number people's bodies aim at can be incredibly different. I was thinking of this after blog reader Megan posted a comment on a previous thread noting that her long-term average was about 8.5 hours/day. She travels frequently for work, and had noticed that in the time colleagues were sleeping, getting a workout in, and having breakfast, she was just sleeping.
On the I Know How She Does It logs, I saw a few women who definitely needed less sleep than other people. One high-energy woman was able to do quite well on 6 hours of sleep a day. She never napped during the week and when I asked about it, she noted that this was how much she slept on vacations too. In her case, it enabled her to run two businesses while being the primary caregiver for her children. A few other people with averages of around 6.5-7 hours/day mentioned not setting alarms. They popped out of bed, alert, with that much sleep.
But other people like Megan need 8.5 hours, or even more. These are normal numbers. While the recommendations keep moving, over the past few decades the recommendation has generally been 7-9 hours/day. It's just that since we all have 24 hours/day, needing 7.5 hours opens up an extra hour per day over someone who needs 8.5 hours. In a year that is 365 hours. In a decade, that's about 3700 hours with leap years. This is the equivalent of almost 2 extra years of full-time work. It's enough to meet — and double! — the recommended aerobic exercise guidelines. Or consider that when I tracked my time for a year, I found I read 327 hours. That's a reasonable chunk, but it's still less time than the gap between needing 7.4 hours and needing 8.5 hours of sleep. And while I might be on the lower side, I am still higher than some people. Looking at my husband, he seems to do OK with 6.5 hours. The ability to stay out until midnight socializing and networking, and then still be alert in a 7:30 a.m. meeting, can be a competitive advantage.
So if you happen to be a higher sleep needs person, what can you do about it?
Unfortunately, I am not sure it's possible to train yourself to sleep less. Some people think it is. However I generally think these people are training themselves to deal with a deficit over the week and then make it up on weekends. And sometimes the catch-up starts by the end of the week. They come in a little later on Friday, or crash in front of the TV Thursday night. A "typical" night is 6 hours but stretches to 7 and then to 8 or 9 over the weekends, coming out to a far more reasonable 7 and change averaged over 168 hours. Over the long run, I generally think that time "saved" by sleeping less than one's biological minimum will be lost in poor focus, mistakes, etc.
Instead, I think the best strategy is to accept reality. We all have our physical limitations; of physical limitations one could be dealt, needing more than 8 hours of sleep is not that tragic as these things go. Instead, as with much in life, it's better to try to make the most of the time you have, rather than wish for time you don’t have.
What does that mean, practically? If you can't stay out late at dinners, try taking people out for lunch or breakfast or coffee, or do other non-night time bonding activities (for all its baggage as a business activity, that is an upside of golf). If you've got an intense work and family schedule, you may not be able to watch as much TV as other people do, but that's probably the easiest thing to sacrifice. Shorter, more intense workouts might be a better bet than longer ones. If you can't stay up late responding to emails and cranking out projects, you will have to emphasize other competitive advantages that don't involve sheer hours of availability. Minimizing distractions and prioritizing work projects are good ideas for everyone, but particularly for people who don't have an extra 90 minutes to play around with daily.
If you've got higher sleep needs than average, how do you structure your life to deal with those requirements?
*Many people with chronic insomnia don't have this catch-up mechanism. Chronic insomnia is a serious medical issue that needs to be treated in its own way.