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It’s probably no surprise that I like to use myself as a guinea pig for various health explorations.  After reading and learning about how the body works, it’s hard not to want to get in on the action and see how it actually impacts your day to day well-being!

One thing I study a lot as an anesthesiology resident is physiology (aka: how the body works)…and since I want to do a fellowship after residency in pain medicine, I especially enjoy learning about the inter-workings of the autonomic nervous system (that whole rest-and-digest, fight-or-flight system you’ve probably heard about).

The Parasympathetic Nervous System

One thing I’ve been interested in lately is the activation of the parasympathetic nervous system–that’s the “rest and digest” one, though nothing in the body is truly that simple–and it’s downstream effects on our sleep, digestion, feelings of happiness, and opportunities to heal. (I’ve written a few articles about the autonomic nervous system so if you want to learn more, you can start here.)

This came up for me when I was in a period of a lot of stress and I knew that the chronic activation of my sympathetic nervous system (that’s the “fight or flight” one) was leading to elevated cortisol (the “stress hormone”, though it’s not all bad) levels and alterations in my hypothalamic pituitary axis.  While that seems like a bunch of medical sounding words jumbled together, what that truly means for many people, especially women, is changes in sex hormone production, changes in blood sugar regulation, and the potential for chronic fatigue/mood changes.  None of which are all that fun. At all!

I also started thinking about this a lot when my husband started a 4 week stint of night shifts.  He was having a really hard time making the switch to sleeping during the day and I was helping him out the best I could with suggestions that have worked for me in the past. (If you’re a night shift worker or just generally have issues with sleeping, you might like this article I wrote on sleep.)

Why Hugs Make Us Feel Good

As  I was reading along about the parasympathetic nervous system, I came across a concept that you’ve probably actually heard about: widespread external pressure over a large portion of our body leads to a global(-ish) parasympathetic nervous system response.  Said another way, it’s one of the reasons you feel calmer and happier when you get a great big bear hug from a loved one. (You might have also heard this is a byproduct of the release of oxytocin–the “love hormone”–and that’s also true.)

In reality, I’m not sure anyone completely knows why this happens.  It could’ve come about as an evolutionary advantage to help reinforce our affinity to development as part of a tribe. It’s could’ve been just one of those random physiological developments that has stuck around. Again, I haven’t found any definitive thoughts on the matter and if you have any other information, please let me know!

So hugs are great, right? And I happen to be one of those people that things hugs should be more prevalent than they currently are. (Be forewarned: if we ever meet, there’s a good chance I’ll give you a hug.  I’m one of those people.)

Parasympathetic System Activation and Sleep Quality

But besides getting (and giving) frequent hugs to our loved ones, how can we use this physiologic parasympathetic nervous system occurrence to our advantage?

The answer, in my opinion, lies in parasympathetic activation for the initiation and maintenance of sleep.  This is what I experimented with for a while and I’ve come around to be quite a big believer in the positive effects.  (My husband also found this helped him get higher quality sleep during his night shift work and while this is all anecdotal evidence and not a report of a big, double blinded trial, I think it still accounts for something. Especially since my husband is a data-driven, evidence-based family medicine doctor.)

The whole premise of this intervention is really straightforward: applying external pressure onto a large-ish portion of your body as you go to sleep helps promote relaxation and allows you to ease into the rest-and-digest (and repair) portion of the autonomic nervous system.

The actionable item is even easier: use a weighted sensory blanket or a stack of regular blankets over an area, such as your torso, to help promote that relaxation response. I haven’t invested in an official weighted blanket yet (though I hope to get the one I linked to above since it’s made from organic millet) but I have folded up regular blankets into a long stack across my chest and abdomen so that I get all the benefits from the external pressure without making me super hot all night.

Side note: weighted sensory blankets have been used in kids with ADHD, behavior problems, and sensory processing disorder with positive results. I plan on getting one for my sister who is currently 11 and has sensory processing issues.

It’s a super simple step but I’ve noticed that I fall asleep faster and wake up less throughout the night.  Besides how well rested I feel in the morning, I’ve been using the data I get from my FitBit HR to correlate the effects and it lines up really neatly (it’s telling me I spend about 30-50% less time in the restless stage of sleep than I did previously).

It Doesn’t Just Stop There

There are even other things we can do to externally influence the output from our parasympathetic nervous system and they’re all generally pretty pleasurable.  Getting a massage, using an acupuncture mat, or even doing the horizontal tango with your significant other can all help us use the autonomic system to our advantage and reap the health gains that follow.

That’s the biggest benefit I see in learning more about how our bodies work: the ability to modulate and positively impact the beautiful systems we already have in place is an incredibly powerful thing!