Zero gravity sleep featured image

After having spent hundreds of hours pouring over hard-to-find books and research papers and having spent years trying out a variety of sleep positions myself, I’ve come to the conclusion that the best sleep position is the zero-gravity position.

In this article, I hope to give you a unique perspective on why this position is truly optimal for the human body, and why you should be sleeping this way.

What is the Zero Gravity Sleep Position

The zero gravity position was initially popularized by NASA as a way to equalize pressure across the body during takeoff.

Interestingly, it was discovered that astronauts in space adopt a very similar position when relaxed. NASA coined this the neutral body posture.

zero gravity position in space
Neutral body postures for six crew members from Space Shuttle mission STS-57. (Source)

Any deviation from this position requires muscular effort, hence the term. [R] [R]

Basically, this is the posture the body assumes in its most relaxed state.

Even when we sleep on our sides, we tend to curl up a bit, we bend our knees slightly and pull our arms in.

We intrinsically find slightly bent arms and legs relaxing.

In fact, the zero gravity position is used in car seat design and hospital beds.

2d representation of fowlers sleep position
The “Semi-Fowlers” position used in hospitals

This position is optimal from a spine and pressure standpoint; and because the upper body is slightly elevated, it prevents brain congestion and breathing difficulties.

But there’s more to the benefits than that…

Benefits of the Zero Gravity Position

Let’s go over the reasons I think this position beats all the rest.

benefits of sleeping in the zero gravity position infographic

1. Brain Congestion and Edema

This is one of the most interesting aspects of this position in my opinion, so we’ll tackle it first.

The cause of migraines is said to be unknown, but let’s go over some interesting facts that invite a theory for causality.

This gets a little sciencey, so bear with me!

  1. Low blood sugar (hypoglycemia) is strongly correlated with migraines and headache prevalence. [R] [R] [R]
  2. Headaches and migraines occur most often in the early morning hours. [R]
  3. Women get far more migraines and headaches than men, especially around their menstrual cycle. High estrogen and low progesterone can lead to fluid retention and bloating, likely leading to a higher incidence of female-related migraines and headaches. [R]
  4. Both men and women have fewer migraines as they age, possibly due to a decline in cerebrovascular capacitance, with women having the majority of migraines and headaches. [R] [R] [R] [R]
  5. Women who used birth control for >3 years were roughly 2x more likely to self-report with glaucoma and ocular hypertension. Women are also at a 2-3x higher risk for glaucoma than men. [R] [R]
  6. Migraines may be a protective mechanism triggered by the brain. [R] [R]
  7. Migraines frequently cease after vomiting, which severely increases blood pressure to the head, likely producing a huge flushing of extracellular fluid. [R]
  8. Longer sleep durations are associated with an increased risk of stroke. [R] [R]
  9. Strokes tend to occur in the first half of the day and early morning, with most occurring in a two-hour window following waking. [R] [R] [R]

Let’s Put That All Together

I think it can be postulated that migraines and headaches likely have something to do with intracranial pressure, hypertension, sleep, and blood sugar levels in the brain.

When sleeping horizontally, your body must lower its heart rate and blood pressure as the pressure in the brain increases.

This leads to fluid retention and swelling in the brain over the course of the 8 hours that the brain and heart are at the same level.

Ask yourself, do you ever wake up with puffy eyes, congested sinuses, eye gunk, general grogginess, or maybe even a headache?

These are all signs of excess fluid pressure buildup in your head. If you experience any of these things, simply sleep elevated for a couple of days and watch them disappear!

It seems that given all the interesting facts above, for some – especially women – the increase in cranial pressure during the night decreases blood circulation, starving the brain of optimal glucose levels for hours.

In the morning, once normal pressure is attained, the brain seizes this opportunity by opening the neck arteries wide, allowing fresh blood, oxygen, and glucose to replenish the brain.

This results in an episode of extreme pain as the expanding blood vessels and arteries push up against nerve tissue.

If you’d like to learn more about this, I highly recommend checking out the book “Get It Up“. While the title is a turn-off for most, it’s a treasure trove of information, and it’s the only book I’ve found that truly explores the science of sleep positions.

2. Optimal Spine Pressure

One of the biggest hurdles to side sleeping is that it almost always creates spine alignment problems.

Beds try to get around this through zoning and all kinds of other things, but your unique weight, body shape, and spine inevitably lead to poor posture when side sleeping.

In the zero gravity position, it’s much easier to obtain a relaxed and neutral spine shape.

This means less pain upon waking, especially for those of you who suffer from low back pain, as well as less general wear and tear on your spine, and deeper more restful sleep due to better comfort.

3. Improved Body Circulation

There’s a reason NASA launches astronauts into space in this position. Because in the zero gravity position, the heart and blood vessels can most optimally pump blood throughout the body against gravity.

In this position, the body is tilted slightly upward with the feet raised above the heart. This can help promote blood flow from the legs back to the heart and lungs, reducing swelling and edema in the legs and feet.

Sleeping on your back also alleviates the possibility of losing circulation to the arms that side sleeping can cause.

Improved circulation can have a number of health benefits, such as reducing the risk of blood clots, improving oxygen delivery to the cells, and promoting the removal of waste products from the body.

4. Less Heartburn and Acid Reflux

Since your torso is elevated in the zero gravity position, you’re far less likely to experience heartburn or acid reflux throughout the night. [R]

Granted, if you’re eating right and not eating right before bed as you should be, this shouldn’t be a problem anyways.

But still, it’s worth noting that digestion is generally going to be better with the help of gravity to keep things moving in a downward direction.

5. Less Snoring and Better Breathing

Since your torso is slightly elevated, there’s less gravity pulling down on your jaw, throat, and lungs.

This leads to easier breathing, less snoring, and a more restful night.

Many of us are warned away from sleeping on our backs due to sleep apnea being positively associated with this position, luckily elevating the torso slightly can severely diminish this issue. [R] [R] [R] [R]

The Best Angles for the Zero Gravity Position

Assuming you already own a flexible mattress (latex is by far the best option for this) as well as an adjustable bed base, we can move on.

In my opinion, there is no right or wrong angle here. You have to find your Goldilocks zone.

But first, what are we aiming for here?

General Guidelines

  1. In general, a minimum of 5° torso elevation is ideal – all we’re looking for is for the head to be above the heart.
  2. Set a maximum torso elevation of 30° – higher than this may impair your ability to relax properly. Those with pressure-related health symptoms may benefit from getting closer to 30°.
  3. Elevate the legs with a slight bend in the knees to a mild level, usually around the heart level. But ultimately, the level that you find most comfortable is ideal.
  • Tip

Check out our guide for Best Adjustable Bed Bases if you’re interested in sleeping this way!

Finding Your Goldilocks Zone

  1. Start flat: You probably sleep flat right now, we call you people flatties. Just kidding. But seriously, don’t just jump right into sleeping at an extreme angle.
  2. Slowly increase: Adjust your torso and leg angle ever so slightly each day, so that you can barely tell anything has changed, this method will ensure that you don’t startle your body and ruin your sleep routine.
  3. Alternate adjustments: If you’re a particularly picky sleeper, consider only adjusting either the torso or leg portion at a time.
  4. Keep going: keep increasing the angle until one day it feels like you went a bit too far, now you just back it up a little bit.

And bam! You’re sleeping in zero-G baby! Welcome to the club flatty.

  • Tip

We have great tips for learning how to sleep on your back if you’ve had trouble with it in the past!

What About Partners?

One issue you may run into when your preferred position, is you and your partner may not end up liking the same angle.

There are two options here:

  1. Agree on a common ground angle you can both live with or…
  2. Purchase a split king so that you can adjust your side of the bed separately.

Malissa and I have a split king, and it’s heavenly. This allows her to sit up to read in bed if she likes while I doze off, and there’s far less motion transfer at night if one of us gets up to pee.

Side Sleeping in the Zero Gravity Position

Yes, you can sleep on your side in the zero gravity position.

In fact, I often do, and it’s far more comfortable than doing so on a flat mattress!

Let me preface by stating that if your chosen zero gravity angle is on the steep side, you probably won’t be able to comfortably assume a side position without compromising your lower back.

However, most people will find that the angle they find most comfortable is fully conducive to side sleeping if/when they want to.

I often fall asleep on my side, only to roll onto my back and spend the whole night there. Some nights I fall asleep on my back and stay that way.

It just depends, but the option is there and it’s completely okay and actually more comfortable side sleeping this way than any other way I think.


I’ve tried sleeping on my stomach, side, and back, on the floor, on futons, etc. for many months, and this is my favorite.

Hopefully, I’ve convinced you to try out the zero-gravity position! It’s really been a game-changer for me personally.

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  1. Should my mattress be returned to a flat position during the day after sleeping in zero gravity position at night?

    1. Hi Janet!

      An innerspring mattress may perhaps need this depending on its construction? We use all latex mattresses and there’s definitely no need to do this with those. Overall it’s probably not something you need to worry about!

  2. What made you choose zero G over sleeping on the floor? I am currently waying both because I want to be stronger and more relaxed muscles when on the floor but zero G sounds good for Buteyko Breathing.

    Also your The Ultimate Guide to Biohacking, Health, and Wellness. link isn’t working. I type out my email and it says submission failed

    1. Hi Richard!

      I’ve spent a large amount of time experimenting with sleeping on the floor (2 years or so, carpet, futons, side, back, etc) and ultimately gave it up because of muscle relaxation. For me, sleep is primarily for the completion of sleep cycles. Anything that disturbs the sleep cycle pattern is detrimental to successful sleep.

      I found that floor sleeping, or hard surfaces in general resulted in a loss of circulation at some point throughout the night, especially if side sleeping. It’s just much more difficult to avoid. So for me I get more restful sleep in a Zero G position on a medium firmness mattress, this alleviates pressure points optimally and allows for longer bouts of uninterrupted sleep.

      As for the ebook, thank you for pointing this out! For some reason the sidebar signup isn’t working and I had no idea. I’ll have to try to get to the bottom of that. It looks like you figured out that the other page works. I just discovered that my ebook sending automation was turned off for some reason so my apologies for that!

  3. That’s very interesting, have you noticed any sleep issues now when forced to sleep like a ‘flatty’ during hotel nights, travels, staying at in-laws etc!
    Is there any data (even your own subjective one) on improved sleep results?

    1. Funny you mention this as both Malissa and I make these jokes about “flatties” when we visit in laws lol

      We adjust quickly, but it certainly isn’t as comfortable sleeping flat once you’ve found your groove in a zero-g bed!

      I’m not aware of any studies or anything, though I hope someone does at some point! I don’t currently use any sleep tracking devices, but hope to one day delve into them and do experiments like this.

  4. Excellent article. I will try the approach you propose, slow up on my new powered base after which i will set as favorite.

    Also learned for foam mattresses, i have pricey new Tempurpedic medium/firm, temperature key to get right sinking feeling. 68-72F. Ideal. Colder , stiffer, warmer, softer.

    So with angle, temperarure, others like dark, cozy sheets, looking forward togetting even better sleep.

    Good sleep is an important , undervalued , aspect of good overall health.

    John Balazic