How to Calm Your Nervous System After Trauma
To calm your nervous system, use simple physical signals, such as a longer exhale, cold on your neck and your feet pressed into the floor, that let your body's brake, the parasympathetic system, take over from fight or flight. Six to try:
· Longer exhale: Breathing out more slowly than you breathe in slows your heart, and five minutes a day of it lowered anxiety in a Stanford trial.
· Cold: Sixteen seconds of cold on the side of the neck slowed heart rate in a randomized trial.
· Grounding: Pressing your feet into the floor, or naming what you can see, touch and hear, brings your attention back into the room.
· Naming the feeling: Putting an emotion into words dampened the amygdala's response in a brain imaging study.
· Movement: A brisk walk soon after stress deepens your breathing and eases muscle tension, Harvard Health Publishing notes.
· Daily basics: Social support, regular exercise and enough sleep are the three ways the American Psychological Association names to reduce stress responses.
After trauma, some of these can stir up distress instead, and the section on why your nervous system won't calm down covers what to do then.
How to calm your nervous system quickly
Start with your breath, the one automatic body function on Harvard Health Publishing's list that you can also change on purpose, and give each step about five minutes before you decide it isn't working for you.
Make your exhale longer than your inhale
Cyclic sighing is built around a long, slow exhale. Breathe in through your nose, take a second, shorter sip of air on top of the first, then let it all out slowly through your mouth. Inhales speed up your heart rate and exhales slow it down, as the Stanford researchers explain.
In their 2023 study, 108 adults, most of them Stanford undergraduates, practiced for about five minutes a day for a month. Every group felt less anxious after each session, and cyclic sighing lifted mood the most, significantly more than meditation.
If you're already breathing fast, skip the big inhale and let the out-breath run slow, as if through a straw. If watching your breath tightens your chest, move on to the next step.
Give your body something cold or solid
Hold a cold pack or a cold, wet cloth against the side of your neck for 15 seconds or so, rest, then repeat. If there's nothing cold nearby, press your feet hard into the floor.
In a 2018 randomized trial with 71 healthy volunteers, 16-second bursts of cold on the side of the neck slowed heart rate. The trial used a lab cooling device and left out people with chronic health conditions, so check with your doctor first if you have a heart or lung condition.
Put the feeling into words
Name what's happening, out loud or silently. "My body thinks I'm in danger. I'm at my desk, and it's Tuesday afternoon." In a 2007 brain imaging study, labeling the emotion in negative images dampened the response of the amygdala, an emotion-processing area. If the words pull you further into a memory, go back to your feet and the cold.
How you'll know it's working
Your breathing slows and your heart rate eases, the relaxation response the National Center for Complementary and Integrative Health (NCCIH) describes. If you still feel keyed up, get moving: Harvard notes that a brisk walk shortly after stress deepens your breathing and helps relieve muscle tension.
Getting out of fight or flight mode
Getting out of fight or flight mode means letting the parasympathetic nervous system, the brake in Harvard Health Publishing's comparison, take over from the sympathetic gas pedal. If your brain keeps reading danger, the HPA axis keeps cortisol flowing, which Harvard compares to "a motor that is idling too high for too long."
Signs of a dysregulated nervous system
In a dysregulated nervous system, "your body stays stuck in high alert or swings between feeling anxious and completely shut down," as Baylor Scott & White Health puts it. The National Center for PTSD's list of typical reactions after trauma includes several that fit:
· Sudden noises make you jump, and you feel on guard even at home.
· Sleep is hard to come by, and you feel worn out during the day.
· Your heart pounds or you feel shaky.
· Your stomach gets upset, and stress can make bloating and nausea easier to feel, the American Psychological Association (APA) notes.
· Tension settles in your shoulders and neck, which the APA links with tension headaches.
· You're more irritable, or it's hard to concentrate.
· Downtime doesn't feel restful, so you keep busy or avoid people, signs Baylor Scott & White lists.
Some of these overlap with the signs of hidden trauma. Severe or long-lasting physical symptoms deserve a doctor's visit first. If the symptoms arrive all at once and then pass, read panic attack or anxiety attack for how to tell the two apart.
If you're having thoughts of harming yourself, call or text 988, or call 911.
Why won't my nervous system calm down?
Sometimes the calming technique itself is the problem. The NCCIH calls relaxation techniques generally safe for healthy people, but it notes rare reports that some might cause or worsen symptoms in people with a history of abuse or trauma. In the Stanford breathing study, 10% of participants reported negative experiences related to the exercises.
If an exercise stirs up more than it settles, stop, or adjust it: keep your eyes open, cut it to a minute or two, or switch to the cold or your feet.
The research has a gap as well. The Stanford study left out people with moderate to severe psychiatric conditions, and the cold trial left out people with depression, so both describe healthy adults better than trauma survivors. In a 2018 review of 50 studies summarized by the NCCIH, relaxation therapy seemed less effective than cognitive behavioral therapy for PTSD, though most of the studies were prone to bias.
A breathing pattern can quiet the alarm for a while, but it doesn't change what keeps setting it off. After a trauma, that is often the memory itself.
Healing a dysregulated nervous system
To regulate your nervous system over the long run, practice the steps on ordinary days, so they're familiar when you need them. In the Stanford study, the mood benefit grew the more days people practiced.
When the alarm keeps returning after a trauma, the longer route is therapy for the trauma itself. The American Psychological Association's PTSD guideline recommends three forms of cognitive behavioral therapy and suggests four more. One of them, EMDR, works directly on the memory: you hold it in mind briefly while following eye movements or another left-right rhythm, which is associated with the memory becoming less vivid and less upsetting. Brainspotting is another approach, explained in what is Brainspotting.
Questions about calming your nervous system
Can 30 seconds reset your nervous system?
Thirty seconds can help in the moment, though it isn't a full reset. The cold trial above slowed heart rate with bursts of 16 seconds. The 5-4-3-2-1 grounding exercise also fits in under a minute: name five things you see, four you can touch, three you hear, two you can smell and one you can taste. If your body has been on alert for months, repeat it often.
What calms your nervous system at night?
The VA's Whole Health Library recommends progressive muscle relaxation at bedtime. Tense one muscle group for five seconds while breathing in, then release it all at once, starting at your feet or your face. The VA advises against it if you have serious injuries or back problems.
Do vagus nerve exercises work?
Some do. Cold on the neck and breathing fewer than 10 times a minute both raised heart rate variability, a measure tied to vagal activity, though the month-long Stanford study found no lasting change in it. Polyvagal theory, from Stephen Porges, goes further and ties vagal pathways to a social engagement system.
It remains contested: in 2023 Paul Grossman argued that its basic premises are untenable or highly implausible, and in 2025 Porges answered his critics.
How long until your nervous system calms?
In the moment it can take minutes, and as a habit, weeks: in the Stanford study, anxiety dropped after single five-minute sessions, and the mood benefit kept growing over a month of practice. After a trauma, most people's early reactions ease with time, the National Institute of Mental Health notes. When they don't, trauma-focused therapy takes longer: EMDR, for example, is typically given once or twice a week for 6 to 12 sessions, according to the APA, and some people need fewer.
About the author
Dave Saunders, LPC-MHSP, NCC, is a trauma therapist in Brentwood, TN, with an office in Maryland Farms, and he works with adults from Nashville and the surrounding area using EMDR and Brainspotting. Read about PTSD and trauma therapy or anxiety therapy, or book a free 10-minute consultation.