What are the causes of shivering, internal trembling of the body even without temperature?

What are the causes of shivering, internal trembling of the body even without temperature?
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Shivering is a state of trembling or a feeling of internal trembling of the body. It is often associated with increased body temperature and fever. However, it can occur without fever.

A state of body shivering or a feeling of internal body trembling may be accompanied by the perception of an unpleasant cold. The shivering occurs involuntarily and cannot be controlled.

Why does the shivering occur and what are its causes, you ask?

There are many reasons.
It is important to note the associated symptoms and the possible triggering factor.

Shivering is not always associated with increased body temperature and fever. It can occur without temperature and without the presence of disease.

We all know it...

Body shivering, chills, feeling tired, and within a few hours a rise in body temperature to fever. A common seasonal flu or frequent cold starts similarly with more symptoms.

This is just one example of the many infectious diseases that accompany us throughout our lives.

Fever without temperature and without illness?
Of course, this condition is also well known.
Just think of situations...

Exhaustion, fatigue, exhaustion. And we already know that fatigue can affect people after mental and physical exertion.

So in this case, the cause is not an infectious or inflammatory disease. The body needs to rest and recharge, to deal with the increased stress and strain during the day.

Winter months, rainy days, staying in a cold environment. These and other causes of hypothermia lead to increased muscle activity to warm the body.

Do you want to know more about the causes of shivering?
What can be behind its occurrence?
How is it related to childhood or pregnancy?
Read on with us.

Shivering, chills and thermoregulation, how and why?

Thermoregulation is the process by which the body maintains its ideal body temperature. A constant body temperature is very important for the proper functioning of the body.

The centre of thermoregulation is the hypothalamus (in the brain). This is where the information that comes from the periphery, i.e. from the peripheral parts of the body, is evaluated (in this context, all parts of the body outside the brain).

There are many thermoreceptors in the skin.

Thermoreceptors control temperature. There are approximately 10 times more cold thermoreceptors in the skin than heat thermoreceptors.

When the ambient temperature is high, the body temperature starts to rise. At this point, the body starts the cooling process.

An example of this mechanism is the dilation of blood vessels (vasodilation) and increased sweating as well as a reduction in heat-producing metabolism.


In the cold, the body temperature drops. That's when the body starts the process of heat production.

The body raises its temperature by multiple mechanisms, such as:

  • constriction of blood vessels (vasoconstriction)
  • Increase in heat production - increases metabolism and therefore the demand for energy intake
  • body shivering, muscle work increases heat production
  • piloerection, i.e. contraction of the smallest muscles of the tiny hairs of the skin - goose bumps

So it's perfectly natural if you...

In cold environments, when we are not adequately protected from heat loss, we shiver and shiver.

Hypothermia can occur for many reasons, not just due to the weather. For more information, read the article.

Did you know:
The elderly and children are more susceptible to hypothermia.
Most of the time, it only manifests itself through a change in their mental state.


Shivering means increased muscle work.
And working muscles require more energy and oxygen.
This manifests itself in increased heart rate (increased pulse) and heart palpitations.

Poanesthetic tremor

A drop in body temperature also occurs during general anaesthesia. By the time the person wakes up after the procedure, they may feel uncomfortably cold and shivering.

Nowadays, despite the ability of anaesthetics to affect body temperature, this phenomenon is less common. The person's body temperature is monitored during the procedure and they are warmed up when it drops.

Shivering or chills when the body temperature is raised

With a common infectious disease such as flu, tonsillitis or other common illnesses, the body temperature rises.

Why is rising body temperature important?

Normal body temperature ranges from 35.8 to 37.3 °C.

Body temperature is affected by:

  • Metabolism
  • activity and muscle work
  • time of day
  • Age
  • mental activity
  • thyroid and adrenal hormones

If a foreign microorganism enters the body, however, the body reacts by raising the body temperature.

Do you want to know why?

The purpose of this increase in body temperature is to make living conditions more difficult for foreign organisms and to boost the body's defenses.

However, the effect of an increase in body temperature is only beneficial up to a certain point.
A fever, i.e. a body temperature above 38 °C, is no longer good.

Read the article:
The wrap effectively helps to reduce fever. Do you know how to do it correctly?

Body temperature and its values in the table

Value Naming Description
35,9-36,9 °C normothermia normal body temperature
37-38 °C subfebrile elevated body temperature
38,1-40 °C febrile fever
40-42 °C overheating hyperpyrexia

Common acute respiratory diseases include influenza, which is a viral disease. Another example is tonsillitis, which is caused by a virus or bacteria (often Streptococcus pyogenes).

Pneumonia is another example of a more serious illness.

Intestinal infections are also common, including salmonellosis, shigellosis, campylobacter infections and hepatitis A. Very often, these diseases are related to poor personal hygiene and the storage, transport or insufficient cooking of food before consumption.

Read also the article: What does food poisoning and dirty hands disease mean?

In addition, these diseases, in addition to an increase in body temperature and shivering, run together with other symptoms such as:

  • Fatigue and malaise or weakness.
  • feeling cold, chilly, cold extremities
  • headache
  • pain throughout the body, joint pain, muscle pain
  • lack of appetite and nausea
  • behavioural changes, irritability, depression, apathy in young children
  • paleness or red colour of the skin
  • increased sweating
  • sore throat

What about shivering in children?

In children, infectious diseases are mainly behind shivering. Seasonally, flu or other flu-like illnesses and colds occur. Especially in young children, laryngitis or epiglottitis is dangerous.

Read also.

Cold and inadequate clothing also play a role.

Interestingly, in young babies, shivering can be a sign of hunger and low blood sugar.

A symptom of the disease even without a rise in body temperature?

Shivering does not always occur only in association with a rise in body temperature. The diseases in which it can occur are numerous. Examples include...

Rheumatic diseases are characterized by two phases. At the time of relapse, i.e., the worsening of symptoms again, shivering may occur.

High blood pressure (hypertension) is a disease that takes place over a long period of time and adversely affects the entire organism. With occasional rises in blood pressure above a certain tolerable value, tremors may be associated with the other symptoms.

Oncological diseases are a large group of diseases that have a wide range of symptoms. Among the general manifestations there is also a trembling of the body.

An allergic reaction is a disproportionate response of the body to a substance - an allergen. A number of mechanisms are involved. It can also involve an unreasonable cold sensation followed by shivering.

Shivering and pregnancy

Pregnancy is characterized by several changes that take place at the level of hormones or metabolism. In the beginning, it is not noticeable externally, but the woman may feel various and vague manifestations.

Examples of such vague problems are:

  • an increase in body temperature
  • thickening of vaginal discharge
  • mood changes, moodiness, tearfulness, anxiety
  • tiredness and faster fatigue, drowsiness
  • breast tenderness and enlargement
  • headache, body pain
  • dizziness and light-headedness, lower blood pressure and predisposition to fainting and collapse
  • morning sickness
  • shivering, chills, frequent feeling of cold
  • more frequent urination
  • changes in appetite
  • and others

With the first signs of pregnancy and throughout the period, it is necessary to be more vigilant against infectious diseases and against fever.

For more information and appropriate drugs to reduce fever, see the article Flu in pregnancy.

Besides the fact that chills with shivering can mark the beginning of pregnancy, it is not good to underestimate them. Pre-eclampsia, eclampsia and the so-called HELLP syndrome are serious conditions.

It manifests itself, for example:

  • headaches
  • abdominal pain, especially in the area below the ribs on the right
  • abdominal cramps
  • fatigue and malaise
  • nausea, nausea or vomiting
  • general symptoms, i.e. flu-like symptoms
  • swelling
  • high blood pressure
  • proteinuria - protein in the urine
  • yellowing of the skin
  • muscle, body cramps
  • difficulty breathing

Read article How to recognize pre-eclampsia in pregnancy

Can it also arise from stress?

Internal restlessness, body tremors and shaking are also present during exhaustion and after increased mental stress.

Prolonged stress, work pressure, interpersonal conflicts and other extreme psychological stress will also manifest themselves externally.

The human psyche is closely linked to the body as a whole. Therefore, it is common to experience problems such as excessive sweating, hot flashes, dizziness and nausea, trembling of the body, limbs and others.

And also in tetany

Nowadays, a common occurrence, especially in young people, is tetany. Tetany is a condition of increased irritability of the central and peripheral nervous system.

The main factor is a deficiency of magnesium and abnormalities of other ions, such as calcium or calcium (Ca).

Starvation and reduction diets are also risky in this context.

Diseases may include kidney dysfunction, central nervous system disorders.

Drugs affecting metabolism, diuretics (drugs for induced urination), laxatives or corticosteroids may also cause it.

Hyperventilation often comes along with tetany.

Hyperventilation is manifested by:

  • rapid breathing, deepened or shallow breathing
  • labored breathing
  • a feeling of inadequate breathing or a feeling of lack of air
  • heart palpitations
  • tension, restlessness
  • body trembling, internal trembling
  • tingling of the body, face, limbs, fingers, lips
  • stiffness of the muscles to cramps in the limbs
  • nausea, feeling like vomiting
  • heaviness in the stomach
  • dizziness
  • and others

Tremor may occur in other cases as well:

How and why tremor occurs in humans

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