What are muscle knots and why do they appear?

Have you ever woken up in the middle of the night wincing due to an excruciating twinge of pain in your shoulder or neck muscles? On touch, does the muscle feel taut and tensed rather than soft and relaxed? You will experience a “muscle knot” or tight band in such scenario. Nearly everyone has suffered this problem at one point or another and the muscle knot doesn’t seem to go away no matter what you do. What’s more, this pain can linger on for days or even weeks. You’d probably be keen to know about muscle knot and why it occurs.

This knot is caused by pain sensations felt at sensitive points in the muscle fiber and adjoining sheath of tissue. As the pain continues, the muscle swells into a bump also referred to as a “muscle knot”. To put in simple words, muscle knots are the trigger points in your muscle, which can cause pain and limitation of muscle activity. The technical name for muscle knots is Myofascial Trigger Points, or MTPS. The size of muscle knot varies according to the size of the muscle affected.

Indicative symptoms to look for

Muscle knots hardly ever show up on scans. Pain is the marker leading to their diagnosis. Symptoms are as under:

  • Deep, throbbing, dull, aching pain in the muscle.
  • Pain persisting over a considerably long duration that usually worsens with time.
  • Difficulty in movement or restricted muscle movement.
  • Tenderness of muscle.

How are They Caused?

Trigger Points

Because muscle knots hardly show up on scans, it has been difficult for medical experts to determine their cause. Generally, it is believed that these muscle bumps are formed when your muscle fibers are contracted for a prolonged time or subjected to overload. Trigger points are extremely sensitive spots in myofascia (tissue covering of muscles) formed in association with nodules in hyper tensed muscle fibers. These triggers point maybe latent or active. The term “trigger point” was first introduced by Dr. Janet Travell to explain clinical findings related to muscle knots.

Trigger points when activated cause pain, burning sensation and weakness. The pain caused by their activation maybe localized or referred. That means that they may cause pain to erupt where they are present and in muscles in other areas as well.

Trigger points are of two types:

  1. Latent trigger points: these are generally less painful when at rest but can become tender when moving or touching them.
  2. Active trigger points: this type of knot is the worse of both since it is painful even when at rest. It tends to be formed by tense tissues and impacts diffuse and large areas of skin and tissues.

Trigger points besides causing you pain, may also restrict the range of motion of the affected muscles. It means that the mobility of your muscles is compromised. It is regained once the muscle bump relaxes. Muscles having trigger points become fatigued more easily than the others. Patients of chronic myofascial pain especially display trigger points as a prominent symptom.

Contraction of sarcomeres

Sarcomeres are the building blocks of muscle fibers. A single muscle fiber consists of more than 100,000 sarcomeres. Sarcomeres are responsible for contracting your muscles. Sometimes they become entangled and remain contracted for longer than usual. When this happens, the muscle fibers become taut like a rope, hence they are termed as a muscle knot. Blood flow becomes restricted to the fibers, cutting off supply of oxygen and nutrients and prompts the sensory endings to cause pain.

Lack of blood circulation

Blood circulation is cut off to muscle fibers as a consequence of activated trigger points. Blood supply is restricted to the muscle bump area (commonly in back, neck and shoulder area) and the muscle tissue is deprived of crucial nutrients and oxygen. Toxic materials and waste build up in the muscle causing spasms, pain and irritation.

Abnormal release of calcium

Abnormal release of calcium into the muscle tissues may also cause a muscle knot. Nerve endings in the muscles release a chemical “acetylcholine” that stimulates the release of calcium which, in turn, is required for muscle contraction. Under stress and trauma, there is an uplift in the release of acetylcholine that automatically leads to more release of calcium. The muscle is contracted for a prolonged period and hence its energy requirements increase. But restricted blood supply impairs the calcium pump and the muscle remains contracted as a muscle knot.

Muscular overload

Our muscles can only bear a certain amount of stress. When that threshold is crossed, muscle fibers become fatigued and taut, leading to the formation of muscle knots. Physical trauma to muscles can take many forms. It can be in the form of a direct injury to your body in an accident or it can be the accumulated effect of years of postural habits that strain some muscles more than the others.

  • Exertion overload

If you bend over to pick luggage that is too heavy for your strength, your back muscles will become painful due to over exertion. Muscle knots formed as a consequence of exertion overload commonly occur in unconditioned muscles. People who take part in weight lifting exercises also suffer from myofascial trigger points when they return to lifting weights after a long hiatus. Exertion overload is common among laborers, gardeners, porters, etc.

  • Muscle Trauma Overload

Physical trauma to a muscle, usually observed in road accident victims or after a fall, can activate trigger points and muscle bumps.

  • Postural Overload

Overstretching or over shortening a muscle for a prolonged time may also cause muscle knots. For instance, if you sit without proper back support at your office desk for long hours, you will develop muscle bumps in your back. Similarly, if you sleep at night without proper neck support, your neck muscles will be sore and tender in the morning.

  • Biomechanical Overload

Many muscles function together to produce body movements. They are divided into two groups, namely as synergists and antagonists. Biomechanical overload happens when one of the muscle groups becomes fatigued due to trigger point activity. Therefore, the whole burden of labor falls upon the other muscle due to the impairment of its partner muscle. Eventually, the other muscle also becomes stressed due to the work overload.

  • Overstimulation

If you are given a task to perform on a repetitive basis that may cause muscular stress, over time muscle knots are formed due to constant strenuous activities. Rounded and protruding shoulders are commonly observed in office workers with overstretched back muscles.

Emotional stress

Anything that increases muscular tension makes it more vulnerable to muscle bumps and knots. Emotional stress and anxiety can create considerable tension in the back and shoulder muscles, making these areas hot spots for trigger point stimulation. Patients of depression and anxiety often suffer from back pain caused by muscle spasm. Pain itself is a depressant and aggravates mental anxiety. Mental stress causes further issues that lead to trigger point activity, especially in the back:

  • Postural changes

Anxiety has a profound effect on human behavior and activity, including the posture they sit in. When we are stressed, we sit in a more slouching posture. Changes in posture summed up with muscle tension from mental stress lead to muscle knots.

  • Inactivity

People suffering from mental anxiety and depression are less active and mobile. Muscles, when used less, become more vulnerable to fatigue and are easily stressed.

  • Hypersensitivity

Under mental duress, one becomes hypersensitive and perception of pain is elevated. In an anxious frame of mind, you will perceive even a slight back pain as being much greater.

  • Chilling temperatures

If you sleep in an air conditioned room or under a ceiling fan and the room becomes too chilly, your muscles might spasm and contract due to the cold resulting in a muscle knot.

Old age

Muscle knots are frequent in aged and elderly people as their muscle fibers are weak and become easily stressed.

Nutritional deficiencies

Your body requires certain vitamins and minerals to function in a healthy manner.  Nutrient deficiencies, especially of vitamin B complex, vitamin C, folic acid and iron, may be a causative agent behind your muscle knots. These micronutrients play an important role in normal muscle activity.

  • Vitamin B1 deficiency

Deficiency of vitamin B1 or thiamin can cause nerve damage, resulting in trigger point activation.

  • Vitamin D deficiency

Vitamin D facilitates muscle activity by absorbing calcium. Low levels of vitamin D can cause osteomalacia which perpetuates muscle pain and knots.

  • Iron deficiency

Iron is required to transport oxygen to the body tissues, including muscles. If there is insufficient iron in your body, the delivery of oxygen to tissues will be stunted as well as the capacity of muscles to utilize oxygen for the production of energy.

Endocrine disorders

Endocrine disorders such as hypothyroidism can also be responsible for causing muscle bumps.


Women are more prone to have muscle knots than men, especially after menopause. Estrogen and progesterone hormone levels fluctuate as menopause nears.

  • Low estrogen levels

Estrogen inhibits release of stress hormone cortisol. During menopause, when estrogen levels are low, cortisol is released in copious amounts, increasing blood pressure and stress causing the muscles to contract more. Therefore, more muscle knots occur.

  • Low progesterone levels

Progesterone has a general calming effect on the body and decreases anxiety. During menopause, progesterone levels drop, muscles become tenser and muscle bumps are formed more frequently.

Bacterial infections

Infections of sinuses, dental abscesses and urinary tracts infections caused by bacteria may aggravate muscle stress.

Viral infections

Viral infections such as flu or herpes may lead to muscle spasm and pain.

Areas were muscle knots are localized

Muscle knots are usually formed in the neck, back and the shoulder regions.


You may have experienced a muscle knot in your neck after sleeping in an awkward posture, after working on a computer or during an episode of mental stress. Referred pain from trigger points in the neck is felt in the head and shoulders also.  Trigger points in the following muscle groups cause neck pain and stiffness:

  • Levator Scapulae:

Levator Scapulae is an elongated, thin muscle found on both sides of your neck. Contraction of this muscle elevates your shoulder blades and helps to rotate the head to the same side. Postural distortions and trauma activate trigger points in this muscle rendering the person unable to turn his head. Tension and stress to this muscle also causes shortness of breath.

  • Trapezius:

It is a large diamond shaped muscle present at the base of your neck. It moves the shoulders blades, head and neck. Poor posture, anxiety, sleeping positions and hypoglycemia (low blood sugar) activate its trigger points. Pain in this muscle brought about by trigger point activity is most markedly felt in the shoulder and along the back of the neck.


Muscle spasms and knots in back are very common, especially in people suffering from some kind of anxiety. The trigger points in back are found in the following muscles:

  • Rhomboids:

This muscle group is located in the middle of the neck. The pain in this region caused by trigger point activity is mostly localized.

  • Quadratus Lumborum:

This muscle is made of many small muscles. It has nearly four trigger points from where pain can be transmitted to lower back, hip and groin regions. Trigger points in this muscle may produce sciatica type pain.

  • Gluteus Medius:

If trigger points in your gluteus medius muscle are activated, you will experience pain during walking and will find it difficult sleeping on your side.

  • Illiopsoas:

This muscle group is formed by the Illiacus and Psoas muscles. It is found deep in the abdominal cavity but its trigger points refer pain to the lower back. If you have a hyper tensed Illiopsoas, you will find it painful to stand and to do a sit up.


The shoulder joint enjoys great mobility. In this regard, the rotator cuff muscles are very important. These muscles are small and are easily affected by strenuous activities. Trigger point activation in shoulder affects the movements of arms and causes frozen shoulder.

Take action now

Muscle knots are very painful and can keep you from performing daily activities, disrupt your work and sleep. To get rid of these, contact a physiotherapist or chiropractor. Massage and stretching exercises have also proved helpful. If you want to get back to being up and about and full of beans, get that muscle knot sorted out immediately!