Classification Fatigue (medical)

physical fatigue

physical fatigue, or muscle fatigue, temporary physical inability of muscle perform optimally. onset of muscle fatigue during physical activity gradual, , depends upon individual s level of physical fitness, , upon other factors, such sleep deprivation , overall health. can reversed rest. physical fatigue can caused lack of energy in muscle, decrease of efficiency of neuromuscular junction or reduction of drive originating central nervous system. central component of fatigue triggered increase of level of serotonin in central nervous system. during motor activity, serotonin released in synapses contact motoneurons promotes muscle contraction. during high level of motor activity, amount of serotonin released increases , spillover occurs. serotonin binds extrasynaptic receptors located on axon initial segment of motoneurons result nerve impulse initiation , thereby muscle contraction inhibited.

muscle strength testing can used determine presence of neuromuscular disease, cannot determine cause. additional testing, such electromyography, can provide diagnostic information, information gained muscle strength testing alone not enough diagnose neuromuscular disorders.

people multiple sclerosis experience form of overwhelming lassitude or tiredness can occur @ time of day, duration, , not recur in recognizable pattern given patient, referred neurological fatigue .

mental fatigue

mental fatigue temporary inability maintain optimal cognitive performance. onset of mental fatigue during cognitive activity gradual, , depends upon individual s cognitive ability, , upon other factors, such sleep deprivation , overall health. mental fatigue has been shown decrease physical performance. can manifest somnolence, lethargy, or directed attention fatigue. decreased attention known ego depletion , occurs when limited self-regulatory capacity depleted. may described more or less decreased level of consciousness. in case, can dangerous when performing tasks require constant concentration, such operating large vehicles. instance, person sufficiently somnolent may experience microsleep. however, objective cognitive testing can used differentiate neurocognitive deficits of brain disease attributable tiredness.

the perception of mental fatigue believed modulated brain s reticular activating system (ras).