Hypertrophy: the growth of muscle cells.


Hypertrophy is defined as an increase in the size of your body's cells, tissues, or organs. Muscle hypertrophy can result from exercise, especially strength training. Weight lifting and constant (and safe) loading of muscle tissue can increase muscle tissue. Hypertrophy should not be confused with hyperplasia, that is, an increase in the number of cells in the body. This is how hypertrophy occurs in the body.

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Muscle anatomy

All of the muscle tissue in your body is made up of cells called myocytes. There are three types of muscle tissue in your body. These include:

  • Cardiac muscle : The heart muscle is a type of muscle cell in the heart.
  • Smooth muscle : This type of muscle is found in the intestinal tract and elsewhere in the body (such as the lungs).
  • Skeletal muscle : Skeletal muscle is muscle tissue that attaches to bone and is used to move the limbs and torso.

Skeletal muscle cells are long, cylindrical, and contain many nuclei. The outer covering of muscle cells is called a sarcolemma and the gel in the inner cell is called a sarcoplasm . In sarcoplasm, myoglobin molecules accumulate oxygen and glycogen molecules accumulate glucose.

Oxygen and glucose provide energy to muscle cells.

Also in sarcoplasm, actin and myosin filaments form protein chains that can slide and slide past each other during muscle contractions .

How does hypertrophy occur?

Hypertrophy is an increase in the size of muscle cells. When muscle tissue is subjected to mechanical stress, myogenic stem cells are activated , resulting in the repair of damaged muscle tissue and an increase in muscle cell size.

These mechanisms include:

  • Cellular inflammation : During exercise, muscle cells use the energy of oxygen and glucose to contract. This leads to increased blood flow to the contracting muscle and temporary inflammation of the cells. The swelling of muscle cells triggers the release of anabolic hormones (such as growth hormone), which lead to the activation of myogenic stem cells .
  • Muscle Cell Damage : When you exercise, you do little damage to muscle cells, which activates myogenic stem cells.
  • Cellular Hypoxia: Hypoxia is a condition in which there is not enough oxygen in the tissues of the body. Resistance exercise can cause temporary hypoxia due to increased oxygen consumption and muscle contraction. Hypoxia indicates the release of hormones that help regulate lactate and growth hormone in muscle cells.
  • Growth Hormone : When you do strength training, growth hormone is released. This hormone acts in the repair of muscle cells and increases muscle strength. Growth hormone also reduces the effects of myostatin , a hormone that inhibits the growth of muscle cells. This disabling of myostatin leads to an increase in muscle cells (hypertrophy).

So how can muscle tissue be safely stressed to trigger the chain of events that leads to muscle hypertrophy? Exercise and movement.

Hypertrophy-inducing methods.

The most effective way to induce muscle hypertrophy is through exercise.

High intensity strength training exercise causes minor damage to skeletal muscle cells and this triggers the release of anabolic hormones that cause muscle hypertrophy.

Think of strength training as creating a little stress and injuring your muscles. Your body's repair of these muscles is tailored to create tissue that becomes slightly stronger, preparing your muscles to effectively handle future stresses they may experience.

Heart muscle

Aerobic exercise has a similar effect on heart muscle tissue. Tension on the heart muscle (within reasonable limits) helps heart tissue grow in response to this stress.

Regular aerobic exercise improves the efficiency of the heart muscle.

Muscle building with injuries.

Sometimes you will not be able to perform high intensity strength training, for example after an injury. But you may still want to create an environment in which muscle growth and hypertrophy can occur.

This is sometimes accomplished through blood flow restriction training . This method of physical therapy involves the use of special cuffs to restrict blood flow to the muscles. Low intensity, frequent repetition exercises are performed, and then the handcuffs are removed. This method has been shown to lead to muscle hypertrophy, even when high load training is not possible .

Be sure to speak with your doctor, physical therapist , or personal trainer before beginning any muscle growth or hypertrophy exercises.

Damaging muscle hypertrophy

Muscle growth is good. This means that you get stronger and exercise regularly. But hypertrophy can also be considered abnormal.

Sometimes your heart can become abnormally hypertrophied. This is called cardiac hypertrophy or left ventricular hypertrophy (LVH).

Causes of LVH can include:

These problems basically make your heart work hard to keep pumping blood throughout your body every day. This overwork puts harmful stress on the heart muscle tissue, resulting in hypertrophy .

Symptoms of cardiac hypertrophy can include:

  • Difficulty breathing
  • Fainting or dizziness
  • Fluttering sensation in the chest.
  • Chest pain

If you have any of these symptoms or suspect a heart problem, see your doctor immediately. They can evaluate your condition and make the correct diagnosis, which will select the right treatment for you.

Pathological conditions associated with skeletal muscle hypertrophy are very rare. One condition, called myostatin-related muscle hypertrophy, is a genetic disorder characterized by low body fat and muscle hypertrophy. This condition is rare and usually does not cause other problems or abnormalities.

Get the word of drug information

Muscle hypertrophy is the growth of individual muscle cells. This causes your muscles to grow more in response to exercise, especially during high intensity resistance training. In most cases, muscle hypertrophy is good; indicates that your muscles are growing or responding normally to resistance exercise. Hypertrophy can sometimes be harmful, especially in diseases of the heart muscle. Understanding how muscle hypertrophy works can help you choose the best way to increase muscle size and improve overall muscle performance.

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