Is there such a thing as good posture?
Posture is the position your body holds against gravity, using a coordinated network of muscles, nerves and sensory systems. Most of it happens without you thinking about it, run by reflexes in your brainstem rather than conscious effort, which is why “just sit up straight” never seems to stick. So rather than good or bad posture, we find it more useful to ask how well your nervous system is holding you up, and what your usual position is telling it.
Yes, slouching can leave you with sore shoulders, headaches or a stiff lower back. But posture goes deeper than how you look in a photo. Your nervous system shapes your posture, and your posture feeds back and shapes your nervous system. We picture it as a hallway with a light switch at each end: flick either one and the whole hallway changes.
Try this now. Sit up tall and take a full, deep breath. Then slump forward and try again. Most people notice the second breath is shallower and harder work, and that’s a small taste of what your nervous system lives with for hours a day.
Think about where those hours go: hunched over the laptop doing admin, looking down at your phone, driving, feeding a baby, folding washing on the couch, scrolling in bed an hour after you promised yourself you’d be asleep etc. Each of them brings your head forward and rounds your upper back. If you’re stressed or scared, notice the position you go into: shoulders up, head forward, hips tight. Your body is getting ready to run, fight or curl up in a ball, and your everyday positions look a lot like it.
What actually shapes your posture?
Your brain builds your posture in real time from three inputs: your inner ear, your vision, and your sense of where your joints and muscles are in space. Change any one of those inputs, or load enough stress or repetition onto the system, and your posture shifts without you ever deciding anything. Old injuries, chronic stress and the positions you sit or stand in for hours a day all feed into it.
Upright posture is also a nervous system achievement before it’s ever a habit. We’re born curled forward, and we grow into extension as the brain develops, which is what lets a baby lift their head, then sit, then stand with their eyes level with the horizon.
What does posture do to the rest of your body?
Your deep, slow twitch muscles are built to hold you upright efficiently for long periods. When your posture drifts, the more superficial, fast twitch muscles end up doing a job they weren’t designed for, which is why they fatigue and ache. Sustained positions also load your ligaments and joints past where they’re comfortable, and that strain builds up over time.
Your breathing changes too. A systematic review of 16 studies found head position affects muscle activity, your sense of where your neck is in space, your breathing pattern and neck pain. That matters because breath is one of the most direct dials on your autonomic nervous system, the part that runs everything you don’t have to think about. A compressed posture nudges that system towards a more switched on state.
Over decades, how well your nervous system keeps that postural tone up is tied to staying independent. Think of how many older people you know who can’t get out of a chair without help.
Isn’t the best posture your next posture?
You’ve probably heard that line, the idea that no single position is bad, only staying still is. There’s truth in it: the body is built to move, not to hold one shape all day. But this fun catchphrase neglects the full picture and is dangerously reductionistic. What it doesn’t take into account is what your default position does to your nervous system, especially the one you fall back into under stress or at a desk. Moving through twenty different positions a day doesn’t help much if every one of them still reads as a stress signal.
What does the research say about posture and the nervous system?
A 2020 study in Gait & Posture compared 80 adults with forward head posture against 80 adults with normal head alignment, matched for age, gender and BMI. Both groups did tests of balance and neck position sense, and researchers measured skin sympathetic response, which shows how strongly the fight or flight side of the nervous system reacts to a stimulus. The forward head posture group did significantly worse on every balance and position test, and their sympathetic response was significantly larger, though no faster. When the head sits forward, the brain gets less accurate information from the neck and the nervous system overreacts. We often describe it as distorted information in, distorted response out.
A 2022 pilot study sat 12 healthy young men in seven positions for 3 minutes each (upright, bent forward, leaning back, side bends and twists) while tracking heart rate variability. The ratio used as a marker of sympathetic dominance was lowest when upright (1.90) and significantly higher when bent forward (2.85), leaning back (3.00) and twisted to the right (4.06). Even relaxed and for only three minutes, holding the trunk away from neutral tipped the balance towards fight or flight. The authors point out that the sympathetic nerve chain sits right alongside the thoracic spine, and suggest bending forward or back may stretch it.
A 2024 study in Healthcare looked at the brain directly. Thirty-three young computer users (17 men and 16 women) who habitually sat with their head forward at the screen had their brain waves recorded for 5 minutes in their usual forward head position and 5 minutes sitting upright, in random order. Gamma wave activity was significantly higher in the forward head position across 16 recording sites, including eight over the frontal lobe and all five over the parietal lobe. At rest, gamma activity is linked with heightened arousal and mental stress, and the researchers concluded that head position itself appears to act as a stressor on the brain.
These studies are small and short, none of them follow people for years, and the first shows an association rather than cause and effect. What they show, from three different angles, is that your nervous system responds to how you hold your body, and it does so within minutes.
So what helps?
If there’s one thing to take from this, it’s to get up and move. Walking is a rhythmic movement that uses both sides of the body, and it restores the upper back rotation and diaphragm breathing that long stretches of sitting shut down. It’s the simplest way out of a fixed, forward-flexed position, and you don’t need any equipment.
Short, frequent breaks seem to matter more than one big block of exercise. In a 2013 trial, 70 healthy adults each did three 9-hour days: sitting the whole time, sitting with one 30-minute walk, and sitting broken up by 1 minute 40 seconds of walking every 30 minutes. The regular breaks lowered blood sugar and insulin after meals more than the single walk did. Two or three minutes, about the length of a song, is enough to count.
A few things we give people to do between breaks:
Posture pole: lie lengthways along a foam roller with your arms open and breathe slowly into your belly. It opens up the compressed sitting position and settles your nervous system at the same time.
Bilateral shoulder abduction: lift both arms out to the side together. It works the upper trapezius and helps counter forward head posture.
Thumb tracking: hold one arm out in front, thumb up, and move it out to the side while following it with your head and eyes. It eases the small muscles at the base of your skull that work overtime when your head sits forward. Do 10 reps every hour to hour and a half.
Getting adjusted addresses something these tools can’t reach on their own: segments of the spine that aren’t moving as they should, which changes the information your spine sends your brain and affects your nervous system well beyond that one area. Adjusting them restores more accurate communication between spine and brain, and people getting adjusted regularly tend to adapt to stress in a healthier way.
If you’d like to talk more about your posture from day to day and how it may be impacting your nervous system function, you can book an initial consultation with us and we’ll let you know how you’re standing (pun intended).
References
Moustafa IM, Youssef A, Ahbouch A, Tamim M, Harrison DE. Is forward head posture relevant to autonomic nervous system function and cervical sensorimotor control? Cross sectional study. Gait & Posture. 2020;77:29–35.
Wang H, Gao X, Shi Y, Wu D, Li C, Wang W. Effects of trunk posture on cardiovascular and autonomic nervous systems: a pilot study. Frontiers in Physiology. 2022;13:1009806.
Jung JY, Lee YB, Kang CK. Effect of forward head posture on resting state brain function. Healthcare. 2024;12(12):1162.
Peddie MC, Bone JL, Rehrer NJ, Skeaff CM, Gray AR, Perry TL. Breaking prolonged sitting reduces postprandial glycemia in healthy, normal-weight adults: a randomized crossover trial. American Journal of Clinical Nutrition. 2013;98(2):358–366.
Szczygieł E, Fudacz N, Golec J, Golec E. The impact of the position of the head on the functioning of the human body: a systematic review. International Journal of Occupational Medicine and Environmental Health. 2020;33(5):559–568.
