Muscle weakness (or "lack of strength") is the inability to exert force with ones muscles to the degree that would be expected given the individual's general physical fitness. A test of strength is often used during a diagnosis of a muscular disorder before the etiology can be identified.

The term subsumes two other more specific terms, true weakness and perceived weakness.

• True weakness (or "objective weakness") describes a condition where the instantaneous force exerted by the muscles is less than would be expected. For instance, if a patient suffers from amyotrophic lateral sclerosis (ALS), motor neurons are damaged and can no longer stimulate the muscles to exert normal force.

• Perceived weakness (or "subjective weakness") describes a condition where it seems to the patient that more effort than normal is required to exert a given amount of force. For instance, a person with chronic fatigue syndrome may struggle to climb a set of stairs when feeling especially fatigued, but if their muscle strength is objectively measured (eg, the maximum weight they can press with their legs) it is essentially normal.

In some conditions such as myasthenia gravis muscle strength is normal when resting, but true weakness occurs after the muscle has been subjected to exercise.

Associated conditions

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• Amyotrophic lateral sclerosis
• Botulism
• Centronuclear myopathy
• Myotubular myopathy
• Charcot-Marie-Tooth
• Hypokalemia
• Motor neurone disease
• Muscular dystrophy
• Myasthenia Gravis
• Progressive muscular atrophy

Muscular strength can be gained by going to the physiotherapist for exercises for individual muscles groups, before pre-typhoid exercise can be attained.

See also

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• Fatigue (physical)
• Asthenia
• Paresis
• Debility
• Cataplexy
• Hypotonia

External links

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• FP Notebook
• MedlinePlus/NIH
• AllRefer

Symptoms