Sleep Smarts #3

1. The single most important fact to remember is that the time when sleep occurs is more important than the duration of the sleep period. You can't fight circadian rhythms! We all have internal clocks that are genetically controlled. These clocks create an internal timing mechanism for sleep. These clocks evolved from dark (night)/light (day) cues. This signal is very primitive because it is based on the rotation of the earth on its axis. Sleeping in synch with circadian rhythms is more restorative, of better quality, than sleeping out of synch with circadian rhythms. Jet-lag syndrome is an example of sleep not in synch with circadian rhythms.

Additionally, a bout of sleep that is continuous (consolidated) is much more restorative than a bout of sleep that in interrupted (fragmented).

2. The Myth of Total Sleep Duration

Some parents observe that their child is getting 12 hours of sleep (e.g. 9pm to 7am plus a 2 hour nap) and therefore they think that there is no problem. Sleep duration is probably less important than sleep quality (intensity, consolidated, and in phase with circadian rhythms).

3. When the Bedtime is Too Late

What occurs when children are allowed to fall asleep too late at night? They wake up short of sleep in the morning. When you are short on sleep, then, even without caffeine, you get "keyed up" because your body produces stimulating chemicals such as cortisol, adrenaline, and noradrenaline. Then, if you suddenly go on vacation, it takes you a few days to "unwind" or dissipate the effects of the stimulating chemicals. This burst of energy is a primitive biological adaptive response so that early man could fight harder, hunt longer, or flee faster for survival. It's like a turbo boost that we often call a "second wind." When present, you are in a state of higher neurological arousal. When the bedtime is too late, he wakes up in the morning in a state of higher neurological arousal which causes him to have difficulty or inability to nap well.

The consequences of not napping well means that by the end of the day his sleep tank is empty and he is in an even higher state of arousal so it becomes more difficult for him to easily fall asleep and stay asleep at night. Parents might not see bedtime battles, long latency to sleep, or night waking as a result from a bedtime that is too late. But of course, he eventually crashes late at night. But this is preceded by an unhealthy state for the child, stressful interactions with him, and stressful interactions as a couple, and stress for each parent as an individual.

Sometimes the naps are very long and late (e.g. 1-4pm) because the bedtime is too late or the child's sleep deprivation is masked by parents returning home from work and playing with the child.

Filed under: Healthy Sleep