Understanding the Autonomic Nervous System for Athletic Performance, Recovery, and Nervous System Regulation
What Is the Autonomic Nervous System? A Simple Guide for Athletes
This blog is Part 1 of a series called The Athlete’s Guide to Nervous System Training for Performance, Recovery & Regulation, where we break down how the autonomic nervous system shapes athletic performance, recovery, and long-term well-being in a way that is practical and relevant to sport.
There’s a lot of information circulating about “the nervous system” and “nervous system regulation” on social media, especially in the context of performance, stress, and recovery. What this blog aims to do is simplify the most important concepts and translate them into what actually matters for athlete well-being, recovery, and performance enhancement.
The human nervous system is a complex system within us made up of the brain, spinal cord, and nerves. It is typically divided into two main branches: the Central Nervous System and the Peripheral Nervous System. Within the Peripheral Nervous System is a specific subsystem called the Autonomic Nervous System (ANS). This is what most people are referring to when they talk about “the nervous system” in the context of stress, regulation, and performance.
Understanding the ANS is essential for athletes because it plays a direct role in how we recover, how we perform, how we respond to stress, and how we maintain long-term physical and emotional well-being.
The 3 Core Jobs of the Autonomic Nervous System (Athlete Performance Lens)
The Autonomic Nervous System has three primary jobs. The first is to keep us alive. This is its most fundamental role. It is called “autonomic” because it functions automatically and below the level of conscious awareness, constantly scanning and responding to cues of safety and threat. At its core, everything the nervous system does is organized around survival and protection, which is the foundation of human functioning and therefore athletic performance.
The second job of the autonomic nervous system is to regulate all involuntary systems in the body that help us function. This includes things like breathing, heart rate, digestion, and other physiological processes that contribute to homeostasis. Homeostasis refers to the body’s ability to maintain a steady internal environment while we adapt to the demands of training, competition, and everyday life (1). For athletes, this is directly tied to energy availability, recovery capacity, and physical consistency.
The third job of the nervous system is to connect the mind and body. The mind and body don’t operate separately and the nervous system acts as the communication bridge between what is happening in the body and what we experience mentally and emotionally. This includes how we interpret internal sensations, how we regulate emotions under pressure, and how we connect and communicate with others, including teammates, coaches, and competitors.
Because of these three core functions, the nervous system becomes a foundational system for athletic performance. You cannot separate performance from physiology, and you cannot separate physiology from the nervous system. Optimal health and well-being are not separate from performance, they are the foundation that makes sustained performance possible.
How the Autonomic Nervous System Works for Athletes
The autonomic nervous system is often described in terms of two main branches: the sympathetic and parasympathetic nervous systems. While this is a helpful starting point, it is important to understand that the system is far more complex than a simple on-and-off switch.
A useful way to understand the autonomic nervous system is to think of it like the gears of a car. We shift between different gears depending on what the situation requires. Sometimes we need to accelerate, sometimes we need to maintain speed, and other times we need to slow down or come to a complete stop. In the same way, the autonomic nervous system is constantly shifting and adjusting to help us respond to the demands of our environment, especially in sport and performance contexts.
At a foundational level, the sympathetic nervous system helps us increase activation or mobilization in the mind-body system. This is often associated with energy, readiness, focus, and performance output. The parasympathetic nervous system helps us decrease activation or mobilization in the mind-body system, supporting recovery, restoration, and physiological regulation. Neither system is inherently “good” or “bad.” Both are essential for survival, athletic performance, and long-term adaptation.
It is also important to understand that the autonomic nervous system is not simply reacting to external events in a logical or linear way. Instead, it is constantly evaluating whether we are safe or under threat, and how much activation is needed to meet the demands of the situation. This shift happens first and foremost physiologically in the body, below conscious awareness, and then influences thoughts, emotions, and behavior.
This is why athletes can sometimes feel anxious, shut down, or overactivated even when they “know” they are safe. The autonomic nervous system operates based on prediction, pattern recognition, and past experience, not just present reality.
Safety States and Protective States in Athletic Performance
Based on how the autonomic nervous system functions, we can understand two broad pathways for experience: safety states and protective states.
We shift into a safety state when the nervous system detects that we are safe. In this state, safety and regulation shape experience. Athletes tend to move through the world with a sense of “I’m safe,” which supports clearer thinking, more flexible emotional responses, better recovery, and more efficient performance.
We shift into protective states when the nervous system detects threat. In this state, threat shapes experience. Athletes tend to move through the world with a sense of “I’m not safe,” which can influence perception, behavior, and performance under pressure.
The most commonly discussed protective state is the stress response, or sympathetic nervous system activation associated with fight or flight. However, both the sympathetic and parasympathetic nervous systems can support safety and protective functions depending on context.
The sympathetic nervous system is primarily a mobilizing system. When the nervous system detects safety, it can support states like play, performance, energy, joy, and what athletes often describe as flow.
The parasympathetic nervous system is often described as the “rest and digest” system, but it also plays a protective role. When the nervous system detects overwhelming or chronic threat, parasympathetic activation can support shutdown, freeze, or collapse responses as a way of conserving energy and protecting the system.
How Athletes Understand Safety and Nervous System Responses
One of the most important concepts to understand is that the nervous system doesn’t always distinguish clearly between actual danger, perceived danger, or remembered danger. All three can activate similar physiological responses in the body.
This means that a high-pressure game, a fear of failure, or literally running from a bear can all be interpreted by the nervous system as a threat. As a result, the body may shift into protective states even when there is no immediate physical danger present.
Safety is also shaped by past experience. The nervous system is constantly comparing present moment information with stored memory in order to predict what is safe and what is not. A great example of this is when you meet someone and immediately feel uneasy, even if you can’t explain why. Later, you realize they reminded you of someone from your past. Your nervous system is using that old experience as data to decide whether you are safe right now. The body is constantly scanning, gathering information, and making predictions about what will help protect you.
Nervous System Flexibility and Athletic Performance Enhancement
This leads to an important point. The goal is not to stay in safety all the time. We are designed to shift between safety states and protective states throughout the day. Athletes need protective states to mobilize energy, rise to challenges, compete, and respond to stress. They also need safety states to recover, connect, learn, adapt, and restore.
The healthiest and highest-performing nervous systems are not the ones that never become activated. They are the ones that can flexibly shift into the state that best matches the demands of the moment and then shift out of that state when it is no longer needed.
This is what I mean by nervous system flexibility.
A flexible nervous system allows an athlete to access activation when performance demands it and access regulation when recovery requires it. It supports physical health, emotional well-being, recovery, resilience, learning, and ultimately sustainable peak performance.
In my work with athletes, I find that many are not struggling because they lack motivation, discipline, or mental toughness. More often, they are operating from nervous systems that have become stuck in protective patterns that no longer serve them.
In Part 2 of this blog series, we'll explore why so many athletes experience nervous system dysregulation and how sport culture itself can sometimes contribute to these patterns.
References
(1)Libretti S, Puckett Y. Physiology, Homeostasis. [Updated 2023 May 1]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK559138/
Training, Lineage & Acknowledgements
I acknowledge that this work is informed by formal clinical training, ongoing professional education, lived experience, and integrative healing traditions. The concepts in this series reflect a synthesis of multiple lineages of knowledge, including trauma-informed care, somatic psychology, and mindfulness-based practice. Many foundational principles of nervous system regulation and embodied healing also have roots in Indigenous traditions and ancient Eastern healing systems, which continue to inform and shape contemporary clinical approaches today.
Polyvagal Theory (originated in the 1970s) developed by Dr. Stephen Porges
Polyvagal Clinical Training with Deb Dana, LCSW
Level I and II, Advanced Trauma Training, The Ferentz Institute
Polyvagal Yoga and Complex Trauma Training, Dr. Arielle Schwartz, PhD
The Hakomi Method, Manuela Mischke-Reeds LA, LMFT, CHT
Help for the Helpers, 2023, Babette Rothschild
Trauma Sensitive Mindfulness, 2018, David Treleaven