Muscle atrophy is the loss of muscle mass. Low physical activity, nutritional deficiencies, genetic factors, and some medical conditions may contribute.
Muscle atrophy due to inactivity can occur if a person remains immobile while recovering from an illness or injury. However, this type of atrophy is reversible with regular exercise and physical therapy. People can treat muscle atrophy by making lifestyle changes, trying physical therapy, or undergoing surgery.
In this article, we look at some other causes, symptoms, and treatments of muscle atrophy.
Many factors can cause muscle atrophy, including the following.
Inactivity
The primary cause of muscle atrophy is inactivity. If a person does not use a particular muscle, the body eventually breaks it down to conserve energy.
Muscle atrophy due to inactivity can occur if someone remains immobile while recovering from an illness or injury. Regular exercise and physical therapy may reverse this form of muscle atrophy.
Inadequate nutrition
Inadequate nutrition can cause numerous health conditions, including muscle atrophy. Diets low in lean protein, fruits, and vegetables can impair muscle growth, or maintenance.
Malnutrition-related muscle atrophy may develop as a result of medical conditions that impair the body’s ability to absorb nutrients. These conditions include:
Cachexia is a complex metabolic condition that causes extreme weight loss and muscle atrophy. It can develop as a symptom of another underlying condition, such as cancer, HIV, or multiple sclerosis (MS).
People who have cachexia may experience a significant loss of appetite or unintentional weight loss despite consuming a large number of calories.
Age
As people age, their bodies produce fewer proteins that promote muscle growth. This reduction of available protein causes the muscle cells to shrink, resulting in a condition called sarcopenia.
Sarcopenia affects up to
In addition to reduced muscle mass, sarcopenia can cause the following symptoms:
- weakness or frailty
- balance issues
- difficulty moving
- lower endurance
Losing muscle mass may be an inevitable result of the natural aging process. However, it can increase the risk of injuries and negatively affect a person’s overall quality of life.
Genetics
Spinal muscular atrophy (SMA) is a group of
Muscular dystrophy is a group of progressive conditions that cause loss of muscle mass and weakness. It occurs when one of the genes involved in protein production mutates. A person can inherit genetic mutations, but many of these alterations occur spontaneously as the embryo develops.
Medical conditions
Diseases and chronic conditions that can contribute to muscle atrophy include:
- Amyotrophic lateral sclerosis (ALS): ALS includes several types that damage the motor nerve cells that control the muscles.
- MS: This chronic condition occurs when the body’s immune system attacks the central nervous system, causing harmful inflammation in the nerve fibers.
- Arthritis: Arthritis refers to inflammation of the joints that causes pain and stiffness. It can severely limit a person’s mobility, which could lead to muscle disuse and atrophy.
- Myositis: This refers to the inflammation of the muscles, causing muscle weakness and pain. People can develop myositis after a viral infection or as a side effect of an autoimmune condition.
- Polio: Polio is an infectious disease that attacks the nervous system. It causes flu-like symptoms and can result in permanent paralysis.
- Mitochondrial dysfunction: Mitochondria are a part of cells that generate most of the chemical energy to power them. Mitochondrial dysfunction affects muscle tissue regulation, among many other processes, and can lead to skeletal muscle atrophy.
Neurological problems
An injury or condition can damage the nerves that control the muscles, resulting in a condition called neurogenic muscle atrophy.
When this develops, the muscles stop contracting because they no longer receive signals from the nerve.
The symptoms of muscle atrophy vary widely depending on the cause and severity of muscle loss. In addition to reduced muscle mass, symptoms of muscle atrophy include:
- having one arm or leg that is noticeably smaller than the others
- experiencing weakness in one limb or generally
- having difficulty balancing
- remaining inactive for an extended period
Treatments for muscle atrophy vary depending on the degree of muscle loss and any underlying medical conditions. Treating the underlying condition causing the muscle atrophy may help slow the progression of the muscle loss.
As some causes of muscular atrophy are incurable, some treatments may aim to reduce symptoms.
Physical therapy
Physical therapy involves performing specific stretches and exercises to prevent immobility. Physical therapy is an effective first-line treatment for muscular atrophy. This approach offers the following benefits to people who have muscle atrophy:
- preventing immobility
- increasing muscle strength
- improving circulation
- reducing spasticity, which causes continuous muscle contraction
Functional electric stimulation
Functional electrical stimulation (FES) is another effective treatment for muscle atrophy. It involves the use of electrical impulses to stimulate muscle contraction in affected muscles.
During FES, a trained technician attaches electrodes to an atrophied limb. The electrodes transmit an electrical current, which triggers movement in the limb.
Focused ultrasound therapy
This technique delivers beams of ultrasound energy to specific areas in the body. The beams stimulate contractions in atrophied muscle tissue. Studies show that focused ultrasound can stimulate muscles and aid in recovery.
Surgery
Surgical procedures may improve muscle function in people with neurological conditions, injuries, or malnutrition-related muscle atrophy.
Targeted mitochondrial therapy
Targeted mitochondrial therapy can help regulate mitochondrial function and improve treatment efficiency in muscular atrophy. This involves transplanting active mitochondria, or carrier cells, to the site of treatment.
Muscle atrophy, or muscle wasting, involves a significant shortening of the muscle fibers and a loss of overall muscle mass.
Several factors can contribute to muscle atrophy, such as:
- remaining immobile for long periods due to illness or injury
- age
- malnutrition
- genetics
- neurological problems
- certain medical conditions, such as arthritis, myositis, amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS)
Treatment options will depend on each individual case but may include physical therapy, nutritional intervention, or surgery.
