Have you ever experienced a muscle that suddenly tightens, contracts, or feels as though it’s locked in place?
Maybe it’s your neck, back, shoulders, legs, or even your feet. The muscle becomes extremely tight, sometimes painfully so, and you can’t seem to get it to relax.
Perhaps you’ve tried stretching, massage, heat, or muscle relaxants, only to have the spasms return.
If this sounds familiar, you may be wondering why your muscles keep tightening and whether your nervous system could be contributing.
Muscle spasms have many possible causes, including muscle strain, dehydration, medication effects, nerve irritation, and certain medical conditions. But the nervous system also plays an important role in regulating muscle activity.
In some people with chronic pain, heightened nervous system sensitivity and protective muscle tension may contribute to recurring discomfort.
Understanding that relationship can help you explore a different way of approaching persistent muscle symptoms.
What Causes Muscle Spasms?
A muscle spasm is an involuntary contraction of a muscle or group of muscles. It may feel like a sudden tightening, a painful knot, a cramp, or a muscle that refuses to relax.
Some spasms last only a few seconds. Others can persist for several minutes or return repeatedly.
Common symptoms include:
Sudden tightening in the neck or shoulders.
Painful lower back spasms.
Calf or foot cramps.
Muscles that feel constantly contracted.
A sensation that a muscle is pulling or grabbing.
Tightness that makes movement uncomfortable.
Repeated spasms in the same area.
Muscle spasms can occur after exercise, prolonged positioning, muscle strain, or overuse.
They can also be associated with dehydration, electrolyte disturbances, certain medications, nerve conditions, and other medical issues.
But there’s another factor worth understanding: the nervous system’s influence on muscle tension and movement.
How Does the Nervous System Control Muscle Tension?
Your muscles don’t operate independently. Their activity is controlled by signals traveling through your nervous system.
Your brain and spinal cord constantly communicate with your muscles, coordinating movement, posture, and protective responses.
When your brain perceives a potential threat, it can increase muscle activation.
Think about what happens when you suddenly hear a loud noise. Your shoulders may rise, your jaw may tighten, and your entire body may become tense before you even realize what’s happening.
That’s a protective response.
The problem is that muscle tension can become persistent when the nervous system remains in a heightened state of alertness.
You might find yourself unconsciously tightening your shoulders throughout the day, clenching your jaw, or holding tension in your lower back.
Over time, this can contribute to discomfort and make certain movements feel more difficult.
This doesn’t mean every muscle spasm is caused by stress or the brain. It means the nervous system is an important part of understanding how muscles function.
Can Nervous System Sensitivity Contribute to Muscle Spasms?
When people discuss neuroplastic pain, they often focus on headaches, back pain, pelvic pain, or burning sensations.
But chronic pain can also involve persistent muscle tension and protective responses.
Imagine that you’ve experienced back pain for several months.
Your brain begins associating certain movements with danger. You become cautious when bending, lifting, or twisting.
Without realizing it, you may start tightening the muscles surrounding your lower back whenever you move.
This protective response can make movement feel more restricted and uncomfortable.
You may begin interpreting every sensation as a warning that something is wrong.
The resulting fear and tension can reinforce one another.
In some people, this type of protective muscle activity may contribute to ongoing discomfort.
However, persistent involuntary muscle spasms are not automatically neuroplastic. They can have many different causes, and the underlying reason needs to be considered.
Why Do My Muscle Spasms Keep Coming Back?
One of the most frustrating things about recurring muscle spasms is that they can seem to appear without warning.
You may have a relatively comfortable day, only to experience another painful contraction the following morning.
There are several possible explanations.
Sometimes the original cause hasn’t been addressed. A muscle may continue reacting to overuse, an underlying injury, nerve irritation, or another physical problem.
In other situations, ongoing muscle guarding may contribute to recurring discomfort.
For example, if you have developed a habit of tightening your neck and shoulders whenever you’re stressed, you may be maintaining muscle tension without realizing it.
You might also become increasingly aware of every sensation in the affected area.
The more concerned you become about another spasm, the more frequently you check the muscle.
You may test your range of motion, stretch repeatedly, or constantly assess whether the muscle feels tight.
This can create a cycle:
You experience a painful muscle spasm.
You become concerned about it happening again.
You begin monitoring the affected muscle.
You become more aware of tension and discomfort.
You respond by tightening or protecting the area.
The muscle remains a source of concern and attention.
This doesn’t mean you’re causing the spasms by worrying about them. It means fear, attention, and protective muscle activity can become part of the overall experience.
Can Stress Cause Muscle Spasms?
Stress can influence muscle tension throughout the body.
When your nervous system activates its protective stress response, muscles may become more tense and ready for action.
You may notice this in your neck, shoulders, jaw, back, or stomach.
During prolonged periods of stress, you may also develop habits such as clenching your teeth, holding your breath, or maintaining a rigid posture.
These patterns can contribute to muscle discomfort.
Stress can also affect sleep and recovery, which may make existing muscle symptoms harder to manage.
However, it’s important to distinguish general muscle tension from true involuntary spasms.
Stress may contribute to tension and discomfort, but it doesn’t explain every episode of cramping or involuntary contraction.
If spasms are frequent, severe, worsening, or unexplained, medical evaluation is important.
Why Does Trying to Relax Sometimes Make Muscle Tension More Noticeable?
Here’s something interesting.
Some people notice their muscle tension more when they finally stop moving.
During the day, they’re distracted by work, conversations, errands, and other activities.
But when they sit down, lie in bed, or try to relax, they suddenly become aware of how tight their muscles feel.
They may start checking their neck, shoulders, or back to see whether the tension has improved.
If it hasn’t, frustration can quickly follow.
This is where attention becomes important.
When you repeatedly monitor a physical sensation, you can make it more prominent in your awareness.
The goal isn’t to ignore your muscles or force them to relax.
It’s to develop a less fearful relationship with familiar sensations while allowing your body to move and rest without constantly evaluating how it feels.
Can Pain Reprocessing Therapy Help With Muscle Tension?
Pain Reprocessing Therapy (PRT) is an approach designed to help people understand and change the way their brains process certain types of chronic pain.
It focuses on the relationship between the brain, nervous system, fear, and physical sensations.
For people whose chronic discomfort involves heightened sensitivity or protective muscle tension, some PRT principles may be useful.
These include:
Recognizing when fear is increasing muscle guarding.
Understanding the relationship between perceived danger and physical tension.
Reducing constant monitoring of uncomfortable areas.
Responding to familiar sensations with less alarm.
Exploring emotional stress that may contribute to ongoing tension.
Gradually rebuilding confidence in movement.
PRT is not an established treatment for muscle spasms themselves, and it should not replace evaluation or treatment of an underlying muscular, neurological, metabolic, or medication-related condition.
The goal is to consider whether nervous system sensitivity may be one contributing factor alongside other possible causes.
A Simple PRT-Informed Exercise for Muscle Tension
If your recurring muscle discomfort has been appropriately evaluated, try this exercise.
Step 1: Notice the tension.
Find a comfortable position and notice the area that feels tight.
You might say:
“My shoulders feel tight right now.”
You don’t need to force the muscles to relax.
Step 2: Notice your emotional response.
Ask yourself:
“Am I becoming frightened or frustrated because these muscles feel tight?”
Perhaps you’re worried that a spasm is about to happen. Maybe you’re anticipating another painful episode.
Recognize that response without judging yourself.
Step 3: Remind yourself that tension isn’t automatically danger.
You might say:
“I can notice this sensation without immediately assuming something is being damaged. I can take care of my body without fighting every sensation.”
This is not a substitute for evaluating new or unexplained symptoms. It’s a way to practice responding differently to familiar sensations.
Step 4: Allow comfortable movement.
If movement is safe and appropriate for you, gently move within a comfortable range.
Avoid forcing a stretch or trying to overpower a spasm.
The goal is to gradually rebuild confidence in your body’s ability to move without treating every sensation as a threat.
When Should Muscle Spasms Be Medically Evaluated?
Although muscle spasms are common, persistent or unexplained spasms deserve attention.
A healthcare professional may consider muscle strain, medication side effects, electrolyte abnormalities, nerve compression, neurological conditions, or other possible causes.
Seek evaluation if spasms are frequent, severe, worsening, or accompanied by weakness, persistent numbness, swelling, or significant changes in movement.
Sudden weakness, difficulty walking, or new bladder or bowel control problems require urgent medical attention.
You should also discuss recurring spasms with your healthcare professional if they began after starting or changing a medication. Don’t stop prescribed medication without discussing it with the prescriber.
The important thing is not to assume that every muscle spasm is either structural or neuroplastic. Sometimes more than one factor may be involved.
You Don’t Have to Spend Your Day Fighting Your Muscles
Living with recurring muscle spasms can be exhausting.
You may constantly stretch, massage, reposition, or monitor your muscles, hoping to prevent the next episode.
And when the spasms return, you may feel as though you’re starting over.
Understanding the nervous system’s role in muscle tension can provide another perspective.
If heightened sensitivity, fear, and protective muscle guarding are contributing to your chronic discomfort, learning to respond differently may become a useful part of your recovery.
You can work on reducing fear around familiar sensations, rebuilding confidence in movement, and developing a healthier relationship with your body.
That doesn’t mean ignoring symptoms or abandoning appropriate medical treatment.
It means recognizing that recovery may involve more than treating the muscle itself.
If you’re struggling with chronic pain and want to explore how Pain Reprocessing Therapy and TMS-informed approaches may help, I’d be happy to talk.
I’ve spent over 1,100 hours coaching people through chronic pain and helping them understand the relationship between the brain, nervous system, and physical symptoms.
Your muscles don’t have to be something you’re constantly fighting. There may be another way forward.
Learn more about working with me: