Fatigue

Fatigue
Fatigue is a state of awareness describing a range of afflictions, usually associated with physical and/or mental weakness, though varying from a general state of lethargy to a specific work-induced burning sensation within one's muscles. Fatigue is a non-specific symptom, which means that it has many possible causes. Fatigue is considered a symptom, as opposed to a medical sign, because it is reported by the patient instead of being observed by others. 
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