Stress, Your Nervous System & Why Your Body Can Feel It Too
Most of us think of stress as something that happens in the mind. But if you've ever noticed your shoulders creeping up towards your ears during a busy week, clenched your jaw without realising it, or felt more "achy" than usual when life gets hectic, you've already experienced the truth: stress isn't purely psychological. It shows up in the body, too.
What stress actually is
Your nervous system runs on a balance between two main modes. The sympathetic nervous system is your accelerator — it's what switches on during a perceived threat or demand, releasing adrenaline and cortisol, increasing heart rate, redirecting blood flow to your muscles, and priming you to respond quickly. This is often called "fight or flight."
The parasympathetic nervous system is your brake — sometimes called "rest and digest." It slows the heart rate, supports digestion, and allows tissue repair and recovery to take place. Both systems are essential. Neither is "good" or "bad." The goal isn't to switch off the sympathetic system altogether — you need it to get out of bed, meet a deadline, or cross a busy road safely. The goal is adaptability: the ability to move between the two states as the situation demands, rather than getting stuck in one.
Why persistent stress can be felt physically
When stress is short-lived, the body copes well. The accelerator engages, the demand passes, the brake takes over, and the system resets. Problems tend to arise when the accelerator stays pressed for too long — when stress is frequent, ongoing, or unrelenting, whether the trigger is physical (an injury, poor sleep, overtraining) or emotional (work pressure, family demands, financial worry, grief).
Under sustained sympathetic activity, several things can happen:
Muscles that brace repeatedly — especially through the neck, shoulders, jaw and lower back — can become persistently tense, which some people experience as tightness, stiffness or dull aching.
Sleep can become lighter and more fragmented, which reduces the body's opportunity to repair tissue and regulate mood.
Recovery from exercise, injury or everyday wear and tear can slow down, because the resources the body would use for repair are being diverted elsewhere.
The nervous system's general "threat sensitivity" can increase, meaning aches, pains and other sensations may be noticed more readily and can feel more intense than they would otherwise.
None of this means stress is "causing" injury on its own, or that physical symptoms during stressful periods are imagined. It means the nervous system and the musculoskeletal system are in constant conversation — what affects one tends to influence the other.
Regulation, not permanent calm
A common misconception is that a healthy nervous system is one that stays calm all the time. In reality, a well-regulated nervous system is one that can rise to meet a demand and then come back down again afterwards — flexibly, and without getting stuck in a heightened state for days or weeks at a time. Think of it less like a light switch (on/off) and more like a thermostat that can respond to what's needed and then reset.
Practical ways to support regulation
You don't need to eliminate stress from your life — that isn't realistic, and it isn't really the goal. Instead, these everyday habits help the nervous system move more easily between gear changes:
Breathwork. Slow, extended exhales (for example, a longer breath out than in) activate the parasympathetic system directly. Even a few minutes can shift how you feel.
Movement and exercise. Regular physical activity helps metabolise stress hormones and is one of the most consistently evidence-supported tools for mood and nervous system regulation.
Sleep. Sleep is when much of the body's physical and emotional "housekeeping" takes place — more on this in next month's blog.
Mindfulness and quiet attention. Practices that bring attention to the present moment — even briefly — have been shown to support parasympathetic activity.
Time outside. Natural light and time in green or open spaces are consistently linked with lower stress markers.
The takeaway
Stress isn't "all in your head," and it isn't a personal failing to feel it in your body. Persistent tension, disrupted sleep, slower recovery and heightened sensitivity to aches and pains can all be part of how a busy nervous system communicates with the rest of you. Supporting regulation — through breath, movement, sleep, mindful attention and time outside — helps that system do what it's designed to do: respond, then reset.
This article is for general information and does not replace individualised clinical assessment. If you're concerned about persistent pain or symptoms, please speak to one of our chiropractors.