Imagine that you’re in the grassy plains a few thousand years back. You’re out alone, gathering plants, when you notice a looming figure in the distance – it’s a hungry lion! As you see it, it sees you. With no weapons on hand, in an instant, your body charges up and you’re sprinting to get back to your village. Your heart pumps faster to send more blood out to your arms and legs, allowing you to run more quickly and with more energy. Your respiration rate increases, bringing more oxygen into your body and powering you up further. You make it back to your village and find sanctuary with loved ones.
This story is an example from a few thousand years ago and although we no longer have to run from lions, it illustrates how our nervous system evolved and the way our brain conceptualizes stress today.
What is the nervous system?
For starters, the nervous system is responsible for sending communications between the body and brain. It’s made up of miles and miles of nerve cells in our brain, spinal cord, and nerves extending throughout our body.
The brain sends signals through the nervous system to keep your heart beating, take a sip from your coffee cup, pet your dog’s head, and release different hormones throughout your body. The nervous system is how I am thinking of words to type and tapping my fingers on the keyboard right now!
With so many miles of nerves and a wide variety of functions, scientists organize the nervous system into many different subsystems. Only two of these are important for our discussion about stress today: the sympathetic and the parasympathetic nervous system.
The sympathetic and parasympathetic nervous system (NS) are a yin and yang of sorts. The sympathetic is responsible for activating the fight or flight response, while the parasympathetic sends cues to our body when it is safe to rest again.
What is the Fight or Flight response?
The sympathetic NS is often called the “fight or flight” system because it flips on the fight or flight response when a stressor arises. Whether you see a lion off in the distance or you receive a stressful text from your boss, your body responds with fight or flight.
In these moments, your brain signals to your body to either fight or flee. Your heart will start beating faster, your breathing rate will increase, and different hormones will start rushing throughout your body. All of this is a coordinated effort to send energy out to your muscles to fight or flee more effectively.
The fight or flight response was necessary to preserve the human race; we all need the help if we’re being chased by hungry predators.
The issue with fight or flight, however, is that it is still triggered in response to modern day stressors: receiving a hefty unexpected bill in the mail, having a difficult conversation with your partner, living in a 3-year pandemic, and more.
In these situations, physically fighting or fleeing is rarely necessary or appropriate. When you have an intense text conversation with your boss, running away isn’t going to solve the issue, neither is challenging them to a duel.
Our bodies are constantly entering fight or flight mode, but we aren’t using the energy it supplies us. This “traps” many of us in fight or flight – our heart rates are increased, hormonal secretions are abnormal, and more. We are living with chronic stress and the myriad of poor health effects due to constant activation of the fight or flight response.
The situation isn’t hopeless, however. The good news is you can move yourself out of fight or flight without sprinting away from your stressors or entering into a fist fight.
How do I get out of Fight or Flight?
As I mentioned above, the parasympathetic nervous system (PNS) is responsible for moving you out of the fight or flight response. The PNS is often called the “rest and digest” system because it sends the energy from your muscles back into your daily activities like digestion and normal hormonal secretions.
In our lion example, the fight or flight response was turned off by a few different factors (these factors also turned on the parasympathetic nervous system):
- Movement. The fight or flight response evolved to do exactly what it says – fight or flee.
Physical activity – whether that’s walking, yoga, or working out – is a powerful way to replace fighting or fleeing. Because we are not literally fighting or fleeing in modern day, we need to release the energy pent up by the fight or flight response and signal to our body that it is safe to enter into a state of calm.
- Positive social connection. In the example, you made it back to the village and celebrated with loved ones.
Connecting with others – through physical affection, laughter, and gatherings – literally soothes the nervous system. It’s a signal to the PNS that you are safe and the fight or flight response is no longer needed.
One specific nerve acts as the on switch for the PNS: the vagus nerve. When you can activate the vagus nerve through physical activity or social connection, you can signal to your body that it is safe to rest and exit fight or flight.
In my next blog, we’re going deeper into the vagus nerve, and the many different ways you can activate it. Check back for more!