Have you ever noticed how your body reacts before an important meeting, a difficult conversation, or even when you're stuck in traffic? Your heart races, your breath becomes shallower, your hands sweat… It's as if your body goes into "alert mode" on its own. On the other hand, when you finish a breathing workout, connect with nature, or simply enjoy a moment of relaxation, it seems like something changes inside: your body slows down, your mind clears, and you feel a sense of relief.

These two responses, which seem so distant, are governed by the same system: the autonomic nervous system, divided into sympathetic and parasympathetic nervous systems. Understanding how this system works is essential not only for taking care of our bodies, but also for transforming how we deal with emotions, limiting beliefs, and stressful situations.

In this article, we'll explore in a simple yet in-depth way how the sympathetic and parasympathetic nervous systems work, how they impact our mental and emotional health, and what practices you can apply in your daily life to find balance between them, achieving more lightness, focus, and purpose in your life.

"The sympathetic and parasympathetic nervous systems are parts of the autonomic nervous system. The sympathetic nervous system accelerates the body in stressful situations (fight or flight response), while the parasympathetic nervous system promotes relaxation, recovery, and balance. Together, they regulate involuntary functions such as breathing, heart rate, and digestion."

What is the Autonomic Nervous System?

The human body is an incredible machine, capable of performing thousands of functions without us needing to think about them. Heartbeat, digestion, breathing, and blood pressure control are all regulated by the autonomic nervous system (ANS).

“The autonomic nervous system is responsible for controlling involuntary body functions such as breathing, heart rate, and digestion.”

This system works automatically, as the name suggests. It is divided into two main branches:

• Sympathetic nervous system: responsible for activation, energy and stress response.
• Parasympathetic nervous system: responsible for calm, recovery and balance.

A simple metaphor helps to visualize: the sympathetic nervous system is the accelerator, and the parasympathetic nervous system is the brake. If you only accelerate, the car breaks down. Conversely, if you only brake, it doesn't move. Therefore, the balance between the two is what allows for a healthy life.

Sympathetic Nervous System: The Alert Mode

The sympathetic nervous system is like a guard on standby, always ready to protect you in risky situations. When it's activated, the body releases adrenaline and noradrenaline, substances that put all organs on alert.

“The sympathetic nervous system prepares the body for stressful or emergency situations by activating the fight-or-flight response.”

The effects of this activation are clear:

• Increased heart rate.
• Faster breathing.
• Dilated pupils.
• Redistribution of blood flow to muscles, heart and lungs.

In practice, this is what happens when you feel nervous before presenting a project, when you feel anxiety before a job interview or even when you hear an unexpected noise at night.

However, the problem arises when this system remains activated for too long. Chronic stress keeps the sympathetic nervous system constantly functioning, which can lead to:

• Anxiety and irritability.
• Difficulty sleeping.
• Constant fatigue.
• Decreased immunity.

In short: sympathy is essential to protect us, but in excess, it exhausts us.

Parasympathetic Nervous System: The Relax Mode

After the storm comes the calm. The parasympathetic nervous system is responsible for activating this state. It reduces the body's activity, conserves energy, and promotes recovery.

“The parasympathetic nervous system is responsible for promoting relaxation, recovery and balance in the body.”

Thus, when this system kicks in, the heart rate slows down, breathing slows down, digestion works better, and the body prepares to rest.

Have you ever noticed the feeling of peace after a nice quiet meal, after practicing conscious breathing or when you simply close your eyes and listen to soft music? That's the parasympathetic in action.

In short, it's what helps us break out of stress's autopilot mode and enter a state of regeneration. Therefore, learning to activate it is essential for those seeking emotional and mental balance.

The imbalance between sympathetic and parasympathetic

We live in a society that constantly pushes us into "alert mode." Above all, excessive commitments, cell phone notifications, professional pressure, and even self-imposed pressure constantly activate the sympathetic nervous system.

The result of this imbalance?

• Concentration problems.
• Anxiety and panic attacks.
• Insomnia and sleep disorders.
• Constant muscle tension.
• Feeling like you can never truly relax.

Furthermore, this constant state of acceleration also reinforces limiting beliefs, such as "I can't handle it," "I'm not capable," "I have to be in control all the time." Thus, the body and mind enter a vicious cycle.

The good news is that there is a way out. If we learn to activate the parasympathetic system, we create an internal space to change these patterns.

The amygdala and neurotransmitters in the sympathetic-parasympathetic balance

The amygdala in activity

When we talk about balance between body and mind, we cannot fail to mention the amygdala, a small structure located in the limbic system, which acts as a true “emotional alarm center”.

“The amygdala is responsible for identifying threats and activating the sympathetic nervous system, triggering the fight or flight response.”

As soon as the amygdala perceives danger, whether it's a real risk, like crossing the street and seeing a speeding car, or an imagined one (like anticipating a stressful meeting), it sends signals to the hypothalamus, which activates the sympathetic nervous system. The body then releases adrenaline and cortisol, preparing you for action.

On the other hand, when we manage to activate the parasympathetic system (with breathing, mindfulness or NLP techniques), the activity of the amygdala decreases. This reduces the flow of stress in the body and makes room for states of calm and mental clarity.

Neurotransmitters in action

The balance between sympathetic and parasympathetic also depends on the action of neurotransmitters, the chemicals that function as messengers between neurons:

• Adrenaline and Noradrenaline: main sympathetic neurotransmitters; increase heart rate, respiration and alertness.
• Cortisol: stress hormone, released in response to the sympathetic nervous system. In excess, it weakens the immune system and increases anxiety.
• Acetylcholine: main parasympathetic neurotransmitter; responsible for relaxing the heartbeat, facilitating digestion and inducing recovery.
• Dopamine: associated with motivation, pleasure, and well-being. Autonomic imbalance can affect its release, reducing energy and increasing apathy.
• Serotonin: essential for mood and sleep regulation; helps stabilize emotional states and reinforces the calming action of the parasympathetic system.
• GABA (gamma-aminobutyric acid): inhibitory neurotransmitter that decreases the excitability of neurons, reducing anxiety and facilitating relaxation.

“Acetylcholine is the neurotransmitter of the parasympathetic system, while adrenaline and noradrenaline are the main neurotransmitters of the sympathetic system.”

In other words, we are not just dealing with two automatic systems, but a true neurochemical symphony, where each neurotransmitter plays its role in keeping the mind balanced and the body healthy.

How to activate the parasympathetic system in your daily life

The balance between sympathetic and parasympathetic systems can be trained. And this doesn't require radical changes, but rather small daily practices that help the body slow down and the mind reorganize.

1. Conscious breathing

Breathing is one of the quickest ways to activate the parasympathetic nervous system.

Practical exercise:

• Inhale deeply through your nose for a count of 4.
• Hold your breath for 2 seconds.
• Exhale slowly through your mouth for a count of 6.
• Repeat for 3 minutes.

This simple exercise already lowers your heart rate and reduces anxiety.

2. Meditation mindfulness

If you've never heard of it, mindfulness It's a type of meditation that trains the mind to be attentive to the present moment, observing thoughts, emotions, and sensations without judging them. Imagine pausing your autopilot to notice what's really going on inside you.

Practices of mindfulness has a direct effect on the amygdala: Neuroscience studies show that regular meditation reduces your activity, strengthening brain regions linked to emotional regulation, such as the prefrontal cortex. This helps you respond more consciously to situations, rather than simply reacting with anxiety or fear.

Furthermore, the mindfulness It increases the release of neurotransmitters like serotonin and stimulates GABA, promoting natural relaxation. It's as if the brain learns to create, on its own, a chemical state of calm and balance.

“Mindfulness reduces amygdala activity and increases neurotransmitters linked to well-being, helping to activate the parasympathetic system.”

3. NLP Techniques: Anchoring

Neuro-Linguistic Programming (NLP) is a set of techniques developed to understand how we create our patterns of thought, emotion, and behavior. And, more importantly, how we can change them.

In other words: NLP shows that we don't react to the world as it is, but rather to the mental map we create of it. If this map limits us, we can reprogram it.

One of the best-known NLP techniques is AnchoringIt's based on the principle that the brain associates stimuli with emotional states. For example, listening to a song that marked your adolescence can immediately bring back emotions from that time. The same happens with smells, places, and even gestures.

Thus, Anchoring uses this mechanism intentionally: you learn to create a “shortcut” between a gesture (or other chosen stimulus) and a desired emotional state — such as calm, confidence, or motivation.

“Anchoring in NLP is a technique that associates a specific stimulus (such as a gesture) with a desired emotional state, allowing you to access it quickly when needed.”

4. Light movement

Many people associate physical exercise only with intense effort, sweat, and pushing themselves to the limit. But when it comes to balancing sympathetic and parasympathetic systems, it's not necessary—and often not even recommended—to overexert your body. What really helps is gentle, steady movement.

Activities such as walking, stretching, yoga Even practices like Tai Chi Chuan, known as moving meditation, also help activate the parasympathetic system. Its slow, fluid movements, combined with conscious breathing, reduce amygdala activity and promote deep relaxation. After all, during these movements, the body releases endorphins and dopamine, neurotransmitters that generate pleasure and relaxation. Furthermore, regular practice reduces the production of cortisol, the stress hormone—which balances the sympathetic system and strengthens the calming response of the parasympathetic system.

"Light movements, such as walking, tai chi chuan, and yoga, help activate the parasympathetic system, reducing stress and promoting natural relaxation."

Another interesting point is that light exercise improves heart rate variability (HRV), an indicator of autonomic nervous system health. People with higher HRV can switch more easily between sympathetic and parasympathetic nervous systems, which translates to greater balance and emotional resilience.

The most important thing here isn't intensity, but consistency. Three short walks a week, done mindfully, can be much more effective than a strenuous run that only exhausts you.

5. Contact with nature

Being in contact with nature is one of the quickest and most effective ways to activate the parasympathetic system. Thus, the simple act of walking in a park, observing trees, or listening to the sound of water reduces stress levels and calms the mind.

Environmental psychology research shows that just 20 minutes of exposure to nature is enough to significantly reduce cortisol, improve mood, and increase feelings of well-being. This phenomenon is known in Japan as shinrin-yoku (forest bathing).

“Contact with nature reduces cortisol, calms the mind and strengthens the action of the parasympathetic system.”

Additionally, nature stimulates the senses in a way that balances neurotransmitters:

• The green of plants reduces the activity of the amygdala, reducing anxiety.
• Natural sounds (wind, running water, birdsong) increase serotonin production.
• Exposure to sunlight promotes the regulation of melatonin, improving sleep.

In other words, nature serves as a natural antidote to urban stress. Spending time outdoors, even for a short time, can be a game-changer in the balance between sympathetic and parasympathetic systems.

NLP, Positive Psychology and Mindfulness as allies

Balancing sympathetic and parasympathetic systems is not just a biological issue, but also a mindset issue.

• NLP: helps reprogram beliefs that keep the body on constant alert.
• Mindfulness: teaches us to be present and notice our body's signals before stress takes over.
• Positive Psychology: redirects focus to emotions and experiences that strengthen the parasympathetic.

“Practices such as mindfulness, NLP, and positive psychology help balance the sympathetic and parasympathetic nervous systems, promoting mental and emotional health.”

This integration creates a virtuous cycle: the mind learns to relax, the body responds, and together they build a lighter, more conscious state.

Practical applications in everyday life

Let's imagine Carla, our fictional friend. She's about to present a project at work and feels her body react: sweaty palms, racing heart, shallow breathing. It's the sympathetic nervous system in action.

If she simply lets her body dictate, she may freeze or lose clarity. But if she applies simple techniques like mindful breathing, or even remembers a positive anchor built with NLP, she quickly activates the parasympathetic nervous system. Within minutes, she feels calmer, more focused, and confident.

This is the power of balance: it's not about eliminating the sympathetic, but about learning to measure when to accelerate and when to brake.

Conclusion

Understanding the sympathetic and parasympathetic nervous systems is more than just scientific curiosity: it's a practical path to transforming your life. Learning to observe your internal signals and apply techniques that stimulate the parasympathetic nervous system can help you gain control over your energy, reduce anxiety, and achieve focus and well-being.

This is the heart of mindset reprogramming: aligning your body and mind so they work for you, instead of leaving you trapped in stress cycles. After all, you have the accelerator and the brake within you. What's missing is learning to use them consciously.

And that's exactly what you'll find in eBook “Reprogram your Mindset: Identify your blocks and start your transformation”In it, you will learn practical techniques from NLP, Positive Psychology, Neuroscience, and Mindfulness to apply in your daily life and achieve greater lightness, focus, and purpose.

FAQ – Questions and answers about the sympathetic and parasympathetic nervous system

1. What is the difference between the sympathetic and parasympathetic systems?

The sympathetic nervous system accelerates and prepares the body for stressful situations, while the parasympathetic nervous system relaxes and promotes recovery.

2. How do I know if I have an imbalance between these systems?

If you are tired, anxious, have insomnia and have difficulty relaxing, your sympathetic nervous system is probably overactive.

3. What happens if the sympathetic system remains active for a long time?

Chronic stress can cause anxiety, fatigue, memory problems, decreased immunity, and cardiovascular disease.

4. What quick exercises can I use to activate the parasympathetic nervous system?

Deep breathing, meditation, light walks, stretching, and contact with nature are effective strategies.

5. Can balancing sympathetic and parasympathetic systems improve my mental health?

Yes, this balance helps reduce anxiety, increase focus, improve sleep, and strengthen emotional resilience.

Image: Freepik

Marcel Castilho

Marcel Castilho is an expert in neuromarketing, neuroscience, mindfulness and positive psychology. In addition to being an advertiser, he also has a Master's degree in NLP – Neurolinguistic Programming. As the owner and founder of the communications agency VeroCom and also of the digital agency Vero Contents, he has been studying human behavior for over 30 years.