How Breathing Affects the Nervous System
Understanding the Connection Between Your Breath, Stress and Wellbeing
Breathing is something we do around 20,000 times every day.
Most of the time, we hardly notice it.
Yet every breath sends information throughout the body, influencing our heart rate, blood pressure, emotional state and nervous system activity.
This is one of the reasons breathing has become an increasing focus of research in areas such as stress management, mental health, sleep and human performance.
While breathing won't eliminate life's challenges, understanding how it interacts with the nervous system can provide practical tools to help us respond more effectively to them.
Let's explore how.
What Is the Nervous System?
The nervous system is the body's communication network.
It receives information from both inside and outside the body and helps coordinate everything from movement and digestion to heart rate, breathing and emotional responses.
One part that plays an especially important role in breathing is the autonomic nervous system (ANS).
The autonomic nervous system regulates many functions automatically, without us needing to think about them.
It has two main branches:
The sympathetic nervous system prepares the body for action. It increases heart rate, breathing rate and alertness when we encounter a challenge.
This is often referred to as the "fight or flight" response.
The parasympathetic nervous system supports recovery, digestion and restoration. It slows the heart rate and helps the body return to a calmer physiological state after stress.
Often described as the "rest and digest" response, it plays an important role in recovery and long-term health.
Healthy nervous system function isn't about staying calm all the time.
It's about being able to move flexibly between these states as life demands.
Breathing Is Unique
Breathing is unlike almost every other function in the body.
Most of the time it happens automatically.
But unlike heart rate or digestion, we can also consciously influence it.
This makes breathing a unique bridge between the conscious and unconscious nervous system.
Every time your breathing changes, your nervous system responds.
Likewise, every time your nervous system changes, your breathing responds.
The relationship works both ways.
What Happens to Your Breathing During Stress?
Imagine you're about to give an important presentation.
Or you're running late for work.
Or your phone rings with unexpected news.
Before you've consciously processed what's happening, your body has already begun preparing for action.
Your breathing may become:
Faster
Shallower
Higher into the chest
More irregular
More likely to occur through the mouth
These changes are completely normal.
They're designed to help prepare the body for short periods of increased demand.
The challenge arises when this breathing pattern becomes our default throughout the day.
Many people spend hours breathing in a way that reflects a stressed nervous system, even when no immediate danger is present.
Breathing Doesn't Just Reflect Stress—It Can Influence It
One of the most fascinating aspects of breathing is that it doesn't simply respond to stress.
It also influences how we experience it.
Research suggests that slower, comfortable breathing may increase parasympathetic nervous system activity and improve measures of heart rate variability (HRV), a marker commonly associated with the body's ability to adapt to stress.¹⁻³
This doesn't mean breathing "switches off" stress.
Nor does it mean breathing exercises are appropriate in every situation.
Instead, breathing offers one practical way of supporting nervous system regulation alongside other healthy lifestyle practices.
The Importance of Carbon Dioxide
Many people believe breathing is simply about getting more oxygen.
In reality, carbon dioxide (CO₂) also plays a vital role.
Healthy levels of CO₂ help regulate breathing, support oxygen delivery to body tissues through the Bohr effect, and contribute to maintaining normal acid-base balance.
When people habitually over-breathe, carbon dioxide levels may fall below what's optimal for efficient oxygen delivery.
This is one reason functional breathing education often focuses on breathing more efficiently, rather than simply breathing more deeply.
What About Slow Breathing?
Slow breathing has received increasing attention in scientific research.
Studies suggest breathing at approximately 4.5 to 6.5 breaths per minute may support parasympathetic nervous system activity, improve heart rate variability and reduce perceived stress in some individuals.²³
However, slower isn't always better.
The breath should remain:
Comfortable
Quiet
Relaxed
Unforced
Forcing slow or very deep breathing may increase breathing effort unnecessarily.
The goal is efficient breathing—not perfect breathing.
Everyday Signs Your Nervous System May Be Under Pressure
Many people don't recognise the early signs that their breathing has changed.
You might notice:
Holding your breath while concentrating
Frequent sighing
Mouth breathing
Tightness through the neck and shoulders
Feeling "wired" despite being tired
Difficulty switching off after work
These signs don't necessarily indicate a medical problem.
Instead, they may simply reflect the body's current response to stress.
Awareness is often the first step towards change.
Practical Ways to Support Your Nervous System Through Breathing
Improving breathing doesn't require complicated techniques.
Small changes practised consistently can make a meaningful difference.
1. Notice Your Breathing
Several times each day, pause briefly and ask yourself:
Am I holding my breath?
Am I breathing through my nose?
Do my shoulders feel tense?
Does my breathing feel rushed?
Awareness often comes before change.
2. Breathe Through Your Nose
Where comfortable and appropriate, breathing through the nose helps warm, humidify and filter the air while supporting more efficient airflow.
If your nose feels blocked, it's worth addressing the underlying cause rather than forcing nasal breathing.
3. Slow Your Breathing
Instead of taking large breaths, allow your breathing to become quieter and more relaxed.
The aim isn't to breathe less.
It's to breathe more efficiently.
4. Gently Lengthen Your Exhale
Some people find that a slightly longer exhalation helps support relaxation.
For example:
Inhale gently for four seconds
Exhale comfortably for six seconds
The breath should always remain comfortable rather than strained.
Nervous System Regulation Is About Flexibility
One common misconception is that we should always aim to feel calm.
In reality, healthy nervous system function involves flexibility.
There are times when increased alertness is exactly what we need.
The goal isn't to eliminate stress.
It's to become better at moving between periods of activation and recovery.
Breathing is one of the many tools that can help support this flexibility.
How The Guided Breath Can Help
At The Guided Breath, breathing education goes beyond teaching breathing exercises.
Sessions begin by understanding your breathing patterns, health history and goals before introducing practical, evidence-informed strategies tailored to your individual needs.
Whether your goal is reducing stress, improving sleep, supporting recovery or enhancing performance, you'll learn breathing skills you can confidently apply in everyday life.
The aim isn't simply to help you feel calmer for one session.
It's to help you better understand your breathing and develop habits that support your long-term health and wellbeing.
Key Takeaways
Breathing and the nervous system constantly influence one another.
Stress naturally changes breathing patterns.
Slower, comfortable breathing may support parasympathetic nervous system activity in some people.
Functional breathing focuses on efficient breathing rather than simply breathing more deeply.
Developing awareness of your breathing can be an important first step towards improving nervous system regulation.
References
Jerath, R., Edry, J. W., Barnes, V. A., & Jerath, V. (2006). Physiology of long pranayamic breathing: Neural respiratory elements may provide a mechanism that explains how slow deep breathing shifts the autonomic nervous system. Medical Hypotheses, 67(3), 566–571.
Laborde, S., Allen, M. S., Borges, U., et al. (2022). Effects of slow-paced breathing on stress and the autonomic nervous system: A systematic review. Psychophysiology, 59(6), e13953.
Russo, M. A., Santarelli, D. M., & O'Rourke, D. (2017). The physiological effects of slow breathing in the healthy human. Breathe, 13(4), 298–309.
Zaccaro, A., Piarulli, A., Laurino, M., et al. (2018). How breath-control can change your life: A systematic review on psychophysiological correlates of slow breathing. Frontiers in Human Neuroscience, 12, 353.
