 | Fatigue physical: Encyclopedia - Fatigue physical
Fatigue (physical)
Fatigue is a state, following a period of mental or physical activity, characterized by a lessened capacity for work and reduced efficiency of accomplishment, usually accompanied by a feeling of weariness, sleepiness, or irritability. It may also follow when, from any cause, energy expenditure outstrips restorative processes and may be confined to a single organ.
Fatigue can also be quite dangerous when performing certain duties that require constant concentration, such as driving a vehicle. When someone is sufficiently fatigued, they may experience microsleeps that can cause them to lose concentration; however, objective cognitive testing should be done to differentiate the neurocognitive deficits of brain disease from those attributable to tiredness.
The sense of fatigue is believed to originate in the reticular activating system of the lower brain.
Fatigue physical - Types
There are seen to be two main types of fatigue; Central and Peripheral.
- Central Fatigue is composed of voluntary or involuntary failure of neural drive affecting either the number of MN recruited, or their firing frequency. Causes include nervous damage and inhibition of voluntary effort coming from hard physical work, illness, worry pain etc.
- Peripheral Fatigue affects the neuromuscular junction or muscle fibres (Motor units) and all steps in propagation of an action potential can be affected.
Combat stress reaction (Battle fatigue), Malaise, Asthenia, Paresis, Debility, Muscle weakness, Muscle fatigue
Fatigue physical - Causes
It is typically the result of working, mental stress, jet lag or active recreation, but also from boredom or disease or simply lack of sleep. It may also have chemical causes, such as poisoning or mineral or vitamin deficiencies.
When chronic (meaning of six months or more duration) it is a symptom of nearly 30 different diseases. Post exertional fatigue, also known as exercise intolerance, is however far more rare, and is primarily found in organic brain diseases, mitochondrial disease, and neuromuscular disease.
- Chronic fatigue syndrome (CFS)
- Depression
- Diabetes
- Hyperparathyroidism
- Hypothyroidism
- Myasthenia gravis
- Addison's disease
- Pregnancy
- Parkinson's disease
See also
- Combat stress reaction (Battle fatigue)
- Malaise
- Asthenia
- Paresis
- Debility
- Muscle weakness
- Muscle fatigue
Lithium - side effect is fatigue (taken for Bipolar Disorder)
Other related archivesAddison's disease, Asthenia, Chronic fatigue syndrome (CFS), Combat stress reaction, Debility, Depression, Diabetes, Hyperparathyroidism, Hypothyroidism, Malaise, Muscle fatigue, Muscle weakness, Myasthenia gravis, Paresis, Parkinson's disease, Pregnancy, action potential, boredom, disease, exercise intolerance, jet lag, microsleeps, mineral, mitochondrial disease, muscle fibres, poisoning, recreation, reticular activating system, stress, vehicle, vitamin, working
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