Muscle weakness develops when a person’s complete effort doesn’t produce a normal muscle contraction or movement. It is also known as reduced muscle strength, muscular weakness, and weak muscles. Short-term muscle weakness can happen to everyone at some point or other, whether a person is sick or simply need rest. For instance, a strenuous workout will exhaust your muscles until you have provided them some time to recover with rest.

Also Read: Muscle Injury: Causes, Symptoms And Treatment
Woman helping the patient with muscle weakness

What Is Muscle Weakness?

Muscle weakness is lack of muscle strength, the causative factors are many and can be due to conditions that have perceived muscle weakness-like muscular dystrophy and inflammatory myopathy, it is the main sign of a different type of skeletal muscle disease. Aside from this, muscle weakness can also be due to low levels of potassium and other electrolytes within muscle cells.

If a person happens to develop continuous muscle weakness with no known causes, then it may be a sign of an underlying health condition.

Voluntary muscle contractions are typically produced when the brain sends a signal via the spinal cord and nerves to a muscle. If the brain, nervous system, muscles, or the connections between them are damaged or affected by any health conditions, then muscles may not contract normally, and it can result in muscle weakness.

Possible Causes Of Muscle Weakness

Several health problems can cause muscle weakness, which includes:

A neuromuscular disorder like muscular dystrophies, multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS)

Autoimmune disease conditions such as Grave’s disease and Guillain -Barre syndrome

Thyroid disorders like hypothyroidism and hyperthyroidism

Electrolyte imbalances like hypokalaemia, hypomagnesemia, and hypercalcemia

Other health conditions that may cause muscle weakness:


Herniated disc

Chronic Fatigue Syndrome (CFS)

Hypotonia is usually present at birth, where muscles lack tone

Peripheral neuropathy



Prolonged immobilization

Alcoholic myopathy

Muscle weakness can also be caused by complications from certain viruses and infections, including:

Viruses and infections can also cause muscle weakness, including polio, West Nile virus, rheumatic fever, and botulism.

Additionally, prolonged usage of certain medications may also result in muscle weakness.

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If a person experiences muscle weakness for which there are no known causes, then seek immediate medical help. The health care provider will do a complete physical examination and enquire about other symptoms and family history. The doctor may also examine the patients’ reflexes, senses, muscle tone and if required may recommend certain tests like

CT scans or MRIs to assess the complete structures of the body.

Nerve tests to monitor, how well the nerves are working.

Electromyography (EMG) test the nerve activity in the muscles.

Blood works to determine any signs of infection.


The doctor would recommend an appropriate treatment plan upon evaluating the cause of muscle weakness, as well as the severity of symptoms.

Some of the treatment modes for health conditions that cause muscle weakness include:

Physical Therapy

The therapist would suggest exercises to enhance the quality of life, is a person suffering from conditions like MS or ALS. Resistive exercise can aid a person with MS in the strengthening muscles that have become weak from lack of use.

For ALS physical therapist may suggest stretching and range of motion exercises avert muscle stiffness and rigidity.

Occupational Therapy

An occupational therapist also recommends exercises to strengthen the upper body and assistive devices that may help a person to go about with daily routine.


Over the counter (OTC) pain relievers can help control pain associated with conditions like:

Peripheral neuropathy



Thyroid hormone replacement is used to treat hypothyroidism.

Dietary Modifications

Altering the diet may help correct electrolyte imbalances. Besides these, the doctor may also recommend patients to take supplements like calcium, magnesium or potassium depending upon needs.


Surgery may also be suggested to treat conditions, such as a herniated disc problem or thyroid disorder.