I don't know about you, but when I sleep, the position I fall asleep in is seldom the position I wake up in. As you are well aware, we all tend to roll around in our beds as we sleep, which naturally leads to a question: What happens when we sleep that causes a comfortable position to suddenly become uncomfortable, forcing us to roll over, reposition ourselves, or change sides?
You would think this question has a simple answer, but the truth is... We don't really know.
Dr. Harriet Hiscock — a pediatric sleep specialist at the Royal Children's Hospital in Melbourne — said "No one that I'm aware of has specifically researched this." She went on to explain that Babies usually start rolling around when they reach four months in age, before which, Hiscock said that "they don't have the coordination or the strength to do it." Even though the mechanism hasn't been studied, some doctors have ideas on why this basic human movement takes place.
Especially in the modern world, we find ourselves being still, in the same position, for long periods of time while conscious. If you pay attention to your movements, you'll find that you probably move around, shift your body into various inhuman positions, stretch a little and let loose. When we are still for long periods of time, we tend to get stiff joints and we'll actually develop pressure-related problems.
Dr. Peter Roessler, who is a fellow at the Australian and New Zealand College of Anaesthetists, said, "I think movement while we are asleep is a protective mechanism to prevent problems developing from prolonged pressure, such as reduced blood flow to certain parts of the skin." This would help prevent us from developing pressure sores when we sleep. He believes that the rolling is triggered when our brain receives warning messages from our pain receptors, telling our bodies that we need to check ourselves before we wreck ourselves (biologically speaking, of course).
Learn a lot more about the science behind restlessness here.
Another Sleeping Shenanigan:
Of course, all of this is preferable to that instance when you're on the brink of falling asleep. All of a sudden, your body starts spazzing out, usually when you're asleep in the worst place possible (where people are sure to notice you've nodded off, like school or church, for instance). Why does THAT happen? Thankfully, we have it covered (kind of).
From our article:
A hypnic jerk (technically known as a myoclonus and also known as hypnagogic massive jerk, a moyclonic jerk, or a sleep start) is an involuntary muscle spasm– so you couldn’t even stop it if you tried – that jerks a person awake. These twitches from hell usually happen in the beginnings of sleep (one of the lightest stages).
Nobody knows why these robbers of sleep occur. There are, as always, some hypothesis to explain them. It’s possible sleep starts are a result of the relaxing of muscles. Other theories suggest that, as the body drifts to sleep, the brain interprets various temperature and breathing changes as falling. One of my personal favorites is the theory which says the body doesn’t know the difference between falling asleep and dying, so (as the picture says), your brain violently jerks your body to make sure you’re still alive and to keep everything functioning.
How do you stop, or at least help prevent these things? The same way you cure every other sleeping ailment – relaxing bedroom, no caffeine, no strenuous activity, comfortable mattress, and white noise machines could also help.