How Does Stress Impact the Nervous System?

If you’re like most people, you may not have an intimate anatomical knowledge of your nervous system. However, you’re probably familiar with the “fight or flight” response, which is governed by the sympathetic nervous system (SNS).

The SNS is an evolutionary mechanism that prepares you to fight, flee, or freeze when danger strikes. While it is useful in true emergencies, chronic activation of the SNS can lead to persistent stress. Stress affects not just the mind but the entire body. It floods the body with stress hormones like cortisol and adrenaline, shuts off important brain functions, and contributes to inflammation.

The Role of the Autonomic Nervous System

Your stress response is part of the autonomic nervous system (ANS), which manages automatic bodily functions such as breathing rhythm, heart rate, digestion, and blood pressure. The ANS is essential for maintaining homeostasis, or a stable internal environment. It has two main branches: one to up-regulate functions and another to down-regulate them.

The SNS up-regulates your body’s responses, preparing you to handle immediate threats. Its counterpart, the parasympathetic nervous system (PNS), balances it out. The PNS is responsible for the “rest and digest” functions that counteract the “fight, flight, or freeze” response. The continuous interplay between the SNS and PNS keeps the body in equilibrium, which is crucial for survival. Stress can be defined as anything that disrupts this homeostasis.

The Role of the Vagus Nerve

The vagus nerve plays a significant role in this balancing act. It is one of the 12 cranial nerves that arise directly from the brain, acting like postal routes delivering information between the body and the brain.

The term ‘vagal tone’ refers to the efficiency of the parasympathetic nervous system. Think of it like muscle tone: better vagal tone indicates a more responsive and balanced PNS. A high vagal tone means that your body can relax faster after stress, maintaining a healthy equilibrium.

How Breathwork Can Help

One effective way to enhance vagal tone and activate the PNS is through slow, deep breathing, especially through the nose. This type of breathing engages the diaphragm, which is connected to the vagus nerve. When you breathe deeply, the diaphragm stimulates the vagus nerve, which in turn communicates with the heart to slow the heart rate and promote relaxation. This helps calm the entire nervous system.

Practical Breathwork Techniques

Here are some practical breath-work techniques to help manage stress and improve vagal tone:

  • Diaphragmatic Breathing: Sit or lie down in a comfortable position. Place one hand on your chest and the other on your abdomen. Breathe in slowly through your nose, allowing your abdomen to rise while keeping your chest still. Exhale slowly through your mouth. Repeat for several minutes.
  • 4-7-8 Breathing: Inhale through your nose for a count of four, hold your breath for a count of seven, and exhale through your mouth for a count of eight. This technique helps regulate the breath and promote relaxation.
  • Box Breathing: Inhale through your nose for a count of four, hold your breath for a count of four, exhale through your mouth for a count of four, and hold your breath again for a count of four. Repeat this cycle to help balance the nervous system.
  • Alternate Nostril Breathing: Close your right nostril with your thumb and inhale deeply through your left nostril. Close your left nostril with your ring finger, release your thumb from your right nostril, and exhale through the right nostril. Inhale through the right nostril, then switch and exhale through the left nostril. Continue alternating for several breaths.

Understanding how stress impacts the nervous system and learning techniques to counteract its effects can greatly improve your overall well-being. By incorporating breathwork into your daily routine, you can enhance vagal tone, promote relaxation, and maintain a healthier balance between the SNS and PNS. This not only helps reduce the immediate feelings of stress but also contributes to long-term health by keeping your autonomic nervous system in equilibrium.