It is likely that at some point during the day, whether while resting or practicing some physical exercise, you have felt weakness in your legs. This symptom can also manifest with a feeling of heaviness, fatigue, tingling and difficulty in normal mobilization.
Leg weakness can occur for many reasons in particular, such as frequent physical exercise, prolonged standing, and even severe diseases such as multiple sclerosis or myasthenia gravis. However, before becoming alarmed you should know all the probable causes and what other symptoms may appear. In this FastlyHealarticle, we will explain in detail what the causes of leg weakness are and the best treatments for this symptom.
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Leg weakness a common symptom
Leg weakness is defined as a lack of muscle strength , a symptom that indicates that extra or additional effort is required to perform common, daily movements such as walking or standing. It is likely that many times it is accompanied by pain in the legs.
It should be clear that leg weakness is a symptom that can be caused by various health problems that, in order to diagnose them, a complete medical evaluation will be required as well as the evaluation of other symptoms that may be associated.
It is common for leg weakness to occur after performing some activity, standing for a long time or walking for a long time without rest, performing work activities and household activities … In these cases, it usually disappears spontaneously, now well , if the weakness persists and lasts over time, it may be related to some diseases or more serious health problems. Next, we explain what are the possible causes of weakness in the legs.
Leg weakness: common causes
Leg weakness and tiredness from over-activity
This is the most common cause of leg weakness and occurs when there is an excess of daily activity, either by increasing the intensity of the exercise or doing the activity repeatedly. This is medically called overuse leg weakness and conditions the appearance of leg injuries such as:
- Bursitis : inflammation of fluid-filled bags that are located in joint places or where there are friction points, it is common for bursitis to manifest itself in the knees, generating a feeling of weakness in the legs.
- Tendinitis: inflammatory process of the Achilles tendon that causes pain in the heel and extends to the leg causing a sensation of weakness and cramp.
Pregnancy can be the cause of weakness in the legs due to the pressure exerted by the fetus. It can in fact cause an increase in volume in the legs and feet causing limitations for daily activity.
Many times there may be weakness in the legs and in any other part of the body in a slight way due to the deficiency of iron and magnesium due to an incomplete or unbalanced daily diet.
Sciatic nerve compression
The sciatic nerve is responsible for the sensation of the thigh, leg, and foot. From the spinal cord it goes down through the hips, crosses each of the glutes and branches into both legs. Any compression of this nerve along its path can cause pain, tingling, numbness, and weakness in the legs, back, and buttocks. Properly, this is not a disease but a symptom caused by other injuries such as:
- Herniation in the spine: a common cause of weakness in the legs is that there is a hernia between the vertebrae of the spine, which is preceded by pressure on the sciatic nerve.
- Pelvic fracture: also a pelvic injury in contact with the sciatic nerve exerts pressure on it, triggering the typical symptoms, tingling, numbness and weakness.
- Spinal stenosis: narrowing of the foramina where the spinal nerves exit the spine. This creates pressure and consequently weakness.
- Tumor: the growth of a tumor mass near the path of the sciatic nerve brings compression and consequently weakness in the legs.
Vascular diseases affecting the legs
Vascular diseases can manifest with weakness in the legs due to arterial and venous diseases. Likewise, blood vessel conditions include diseases such as:
- Peripheral arterial disease: this condition is characterized by the narrowing or obstructive process of the artery, bringing with it an inadequate blood supply to the extremities and generating cramps, numbness and pain in the legs, especially after exercising or after walking in short or long distance. Fortunately, this condition improves with rest. It is so called since it affects exclusively the arteries and not the veins.
- Thrombophlebitis: it is generated by a blood clot that is located in a deep vein, representing a serious condition. It is the result of recent bone surgery, bed rest for a long period of time, prolonged immobilization by a cast or splint of an extremity. Symptoms such as:
Thrombophlebitis can be superficial when the clot is located in a vein below the surface of the skin or when it is located in a deep vein, called deep vein thrombosis . The latter would not only affect the leg but can leave other types of complications after the detachment and displacement of the clot, such as pulmonary embolism.
The diseases of the arteries can cause other injuries such as:
- Arterial obstruction related to the presence of a kind of waxy or “atherosclerotic” plaque within an artery, limiting blood flow. Consequently, this causes pain, cramping, heaviness and weakness in the legs.
- Buerger’s disease: This is a rare disease related to high cigarette smoking, where swelling occurs in the small and medium artery of both the legs and feet. This swelling in turn generates narrowing in the peripheral vessels causing lack of oxygen, that is, ischemia and in more serious cases, necrosis or death of the tissue. This obstructive process produces a feeling of coldness in the legs, weakness and pain when walking.
The venous diseases can cause:
- Phlebitis where there is swelling of a vein near the surface of the skin on the leg, the affected area hurts, becomes red, starts weakness and cramps. Immediate medical treatment is needed.
- Ischemic cerebrovascular disease in which there is a decrease in cerebral blood supply. It causes weakness, tingling, numbness and even loss of function in one or both legs.
Other diseases that can cause leg weakness
There are a series of much more complex diseases that are related to the presence of weakness in the legs:
This is an autoimmune disease that affects both the brain and the spinal cord. It is usually diagnosed between the ages of 20 and 40, being much more frequent in women than in men. It occurs when there is damage to the myelin sheath (a covering that protects neurons), slowing or stopping nerve impulses. The symptoms are innumerable and vary according to the location and magnitude of the attack, the most frequent are:
- Loss of balance
- Weakness in the legs
- Dificulty to walk.
- Difficulty in coordinating movements.
- Tremors in legs and arms
Amyotrophic Lateral Sclerosis
It is another rare disease but it can cause weakness in the legs. The ALS affects nerve cells in the brain, spinal cord and brainstem that are responsible for acting on the movement of voluntary muscles of the body. Its cause is still unknown, however, at least 1 in 10 cases is related to genetic or hereditary factors. In the case of amyotrophic lateral sclerosis, neurons wear out and fail to send the proper messages to the muscle, causing muscle weakness, muscle disability, and spasms in both the arms, legs, and body as the disease worsens.
A syndrome that represents a serious health problem, since it mistakenly affects the nervous system through the body’s immune system, that is, it is a serious autoimmune disease that brings inflammation of the nerves, triggering paralysis and muscle weakness. Guillain Barré syndrome is most common between the ages of 30 and 50.
The weakness increases as the days go by, starting in the legs and extending to the arms. According to the Journal of Clinical Research  , it is indicated that 28 patients were studied for 10 years at the Salvador Zubirán National Institute of Medical Sciences and Nutrition, of which 93% had a typical clinical presentation with ascending limb weakness .
Distrofia muscular de Becker
This is a rare inherited disease that affects the legs and pelvis, generating muscle weakness that slowly and progressively worsens. There is a greater risk of developing Becker muscular dystrophy if there is a direct relative who suffers from it, that is, from parents to children.
Symptoms can begin to appear between 5 and 15 years of age and is basically characterized by muscle weakness in the legs and pelvis, slowly and progressively worsening, including frequent falls and difficulty getting up from the floor.
Myasthenia gravis is an autoimmune disorder that directly involves muscles and nerves, directly and mistakenly affected by the body’s own immune system. This condition directly involves the voluntary muscles of the body, getting worse with daily activity and improving with rest.
Among all the symptoms that can occur after suffering from myasthenia gravis, there is muscle weakness in the legs causing difficulty in climbing stairs or getting up after sitting. This disorder has an incidence of 5 per 100,000 people according to the Rosario Neurology Center  .
General measures for leg weakness
In general, some general measures can be used to improve the feeling of weakness in the legs , however, a medical evaluation is necessary in any of the aforementioned cases to indicate the specific treatment:
- It is advisable to reduce daily activity to avoid exacerbation of weakness in the legs.
- Do light exercises to stimulate circulation in your legs. It is recommended to stand up and gently move your legs.
- Sit in high chairs to facilitate blood flow.
- Maintain proper leg postures to avoid overload.
- Avoid standing for long periods of time.
- Wear comfortable and comfortable shoes.
- Alternate hot and cold baths on your legs.
- Eat a balanced diet in terms of vitamins and minerals and use vitamin supplements if necessary.
- Avoid cigarette smoking.
- If you have a history of vascular disease, see your doctor for a regular medical evaluation.
- Physiotherapy will be indicated depending on the case and its severity.
- In many cases, the doctor will order orthopedic support such as wheelchairs.
- Avoid stress, do relaxation therapies.
This article is merely informative, at FastlyHeal .com we do not have the power to prescribe medical treatments or make any type of diagnosis. We invite you to see a doctor in the case of presenting any type of condition or discomfort.
If you want to read more articles similar to Leg weakness: causes and treatments , we recommend that you enter our Bones, Joints and Muscles category .
I am a Surgeon with a diploma in comprehensive ultrasound and surgical care residency, an area I am specializing in. During the exercise of my profession, I have realized the need for patients to know the diseases they suffer, and I can tell you that a large part of their complications is due to a lack of information. Being a health web writer allows me to transmit my experience, without borders, to all those readers eager for knowledge, educate them in the prevention of diseases and promote a healthy lifestyle.