Causes of muscle fatigue is a tired feeling that occurs in the muscles of the body due to lack of energy or muscle strength.
These conditions require the muscles to get a break.
A study showed that muscle fatigue is a term used to indicate a temporary decrease in the capacity of muscle organs to perform physical activities.
Muscle fatigue can also be interpreted as a decrease in maximal strength or muscle power capacity.
Causes Muscle fatigue can be known in EMG signals as increased amplitude and decreased characteristic spectral frequencies. Usually, the sensation of fatigue that occurs is a change in awareness in the control system homeostasis unconscious.
A study that used functional magnetic resonance imaging (fMRI) to determine the relationship between mental fatigue and oxygen levels in the blood showed a brain response depending on cognitive tasks.
Muscle fatigue can affect the motor system, perception or decreased mental function can also describe a gradual decrease in muscle strength capacity or the end point of sustainable activity, and can be measured as muscle reduction, electromyographic activity changes or contractility fatigue.
Causes of Muscle fatigue can be classified into 2, namely:
- Fatigue of the central system, namely fatigue that occurs in the central nervous system. This is due to the failure of the central nervous system to produce quantities and activate the motor cells involved in muscle contraction. With the reduced number and frequency of motor cells activating muscle contraction ability decreases.
- Fatigue purifier, namely fatigue that occurs outside the central nervous system. This is due to the inability of the muscles to perform contractions maximally as a result of several factors such as nervous ability disorders, the mechanical ability of muscle contraction, and the availability of energy to perform contractions.
How does muscle fatigue occur?
Manifestations of muscle fatigue as observed during a decrease in ability to produce strength after intense activity.
If the activity continues, it will result in sustained weakness that can last for days or even weeks.
Activity can bind heavy pressure on various organ systems, resulting in decreased function and performance in some tissues and body cells.
Under these circumstances, the utilization of adenosine triphosphate (ATP) will be accelerated dramatically in an effort to meet the energy needs of the major processes involved in excitation and contraction.
To maintain ATP levels, high-energy phosphate transfer, high glycolysis and oxidative phosphorylation will be required. With intense activity levels, ATP production cannot match the ATP utilization rate, and ATP reduction occurs accompanied by accumulation of various metabolism by hydrogen ions, inorganic phosphates, AMP, ADP, and IMP which are believed to disturb the Na + / K + balance, Ca2 + motor and interaction of actomyosin, thus causing fatigue in the muscles. This type of fatigue is often referred to as metabolism.
Cessation of activity and energy normalization are very useful in the recovery of muscle strength.
Doing activities with high intensity can also cause the depletion of intracellular substrates and glycogen.
Where glycogen is the basic fuel used to maintain both glycolysis and oxidative phosphorylation. When glycogen runs out due to an activity, muscle fatigue will occur.
Intense activity can also lead to non-metabolic fatigue and weakness as a consequence of disruptions to internal structures mediated by high-strength levels.
The most noticeable type of disturbance after eccentric muscle activity can be characterized by myofibrillar disorientation and damage to the cytoskeletal skeleton.
Activities that use high levels of strength can increase muscle damage that gets worse.
Conducting activities that require extra energy results in the need for higher frequency of muscle fibers and motor units.
Another opinion states that chemically the occurrence of muscle fatigue due to reduced energy reserves that increase the metabolic system as the cause of loss of muscle efficiency.
Causes of muscle fatigue?
The causes of muscle fatigue can be caused by many factors, ranging from an accumulation of metabolites in muscle fibers to inadequate motor-order generation in the motor cortex to the absence of a global mechanism responsible for muscle fatigue.
Muscle fatigue can result from overwork, lack of sleep, worry, boredom, anxiety, depression, or lack of exercise.
Symptoms like this may be caused by illness, medication, or medical treatment such as chemotherapy.
Muscle fatigue is not a disease, it is a symptom that can be caused by various problems, such as health problems and others. These symptoms will usually disappear by itself for several days.
Although rare, causes of muscle fatigue are generally caused by several factors, such as:
- Doing intensive activities. Doing activities that are too intensive/heavy can cause decreased performance of muscles or muscle fatigue. Doing heavy activity over a long period of time can affect the body’s motor system which is generally defined as a decrease in a person’s ability to exert force.
- The buildup of lactic acid. The high level of muscle fatigue is closely related to the amount of muscle ability to form lactic acid. The buildup of lactic acid in the muscles can inhibit muscle function.
- Disposal of ATP and PC storage. ATP is an energy source directly used for muscle contraction, and PC is used for ATP Resynthesis as soon as possible. When ATP and PC are used for continuous contractions, fatigue may occur. This is due to the discharge of intracellular phosphagens. In addition, due to the buildup of lactic acid in bone, the concentration of H + ions in intracellular increases.
- Glycogen emptying of the muscles. Glycogen reserves can occur vacuum as glucose in the blood decreases. As a result, local muscle fatigue can occur, dehydration and lack of electrolytes in the body, and can cause body temperature to increase.
- Minerals disorders in the body. Problems with minerals (electrolytes) are found naturally in the body, such as low levels of potassium or sodium.
- Some types of infections such as urinary tract infections or respiratory infections can also cause muscle fatigue effects.
- Problems with the thyroid gland. The thyroid gland is a body organ that regulates the way the body uses energy. Low thyroid levels (hypothyroidism) can cause fatigue, weakness, lethargy, weight loss, depression, memory problems, constipation, dry skin, cold resistance, rough and thinning hair, brittle nails, or yellowish skin.
- Guillain-Barré Syndrome. Namely, a rare nerve disorder that causes weakness in the limbs, arms, and other muscles and can develop in paralysis.
- Myasthenia gravis. That is a kind of chronic disorder that is rare and can cause rapid muscle weakness and fatigue.
Causes muscle fatigue may gradually become more severe, requiring medical treatment. Sudden muscle fatigue can lead to loss of body area function and can cause serious problems in the brain (such as stroke or transient ischemic attack) or spinal cord or with certain nerves in the body.