The ultradian rhythms of the human body haven't received the publicity afforded to our circadian rhythms. But recognized or not, ultradian rhythms are pillars supporting your health. They tick along whether you know about them or not, but you'll be in better fettle if you work in harmony with them.
Like dealing with a cowlick, trying to go against its foreordained direction can be an exercise in futility and a drain to your well-being. You will only wear yourself out in the skirmish and the natural order will still ultimately prevail. So save yourself the grief and get on board with the ultradian rhythm.
Your body likes to take a rest from activity every hour and a half or so. It likes this so much, many body functions are built around your ultradian rhythms.
The ultradian rhythm strongly recommends that after 90 minutes of busy-ness, you should take a 20-minute break. During this break, your body has a little burst of regeneration and a creation of energy that makes getting to the next break 90 minutes later less stressful and draining.
And when these rhythms are disrupted too frequently, your body and brain bear the consequences. This can result in illness, cognitive problems and mood disorders.
In the realm of human beings, the circadian rhythm is central to sleeping and waking. Ultradian rhythm's claim to fame are in the arena of rest and activity, but make an essential appearance in your sleeping habits.
This pattern of 90-minute activity, 20-minute break, are a 24-hour-a-day affair, happening not just while we're awake but all through our supposedly uneventful sleep as well.
Many sleep disorders may be due to malfunctions of the ultradian rhythm. REM (rapid eye movement) sleep appears every 90 minutes or so throughout the night. Each of these cycles involves deep sleep, then REM sleep.
At the end of these 90-minute ultradian rhythms, we tend to resurface toward wakefulness. We turn over, rearrange the covers, nuzzle deeper into the pillow, then sink back into sleep again. With each round of ultradian rhythm, the length of time spent in deep sleep becomes shorter and REM sleep time lengthens.
All of this underscores the fact that while the body is a very busy place, even during sleep, it also places a high value on rest. So much so that it sets you up to need rest off and on all day long every day.
Rest, and its big brother, sleep, are essential times of rebuilding and strengthening. Your body knows you need this. You will flourish if you embrace this fact and make room for it in your daily life.
REM sleep ultradian rhythm
Daily Sleep and Dream Cycle