Pain in muscle.

A functional motor deficit where individuals whose responses to the challenges of exercise fail to achieve levels considered normal for their age and gender.

Weakness of the limb-girdle muscles (also known as the pelvic and shoulder girdles), that is, lack of strength of the muscles around the shoulders and the pelvis.

Asthenic habitus refers to a slender build with long limbs, an angular profile, and prominent muscles or bones.

Obstructive sleep apnea is a common, chronic, complex disease associated with serious cardiovascular and neuropsychologic sequelae and with substantial social and economic costs (Palmer et al., 2003).

The term gait disturbance can refer to any disruption of the ability to walk. In general, this can refer to neurological diseases but also fractures or other sources of pain that is triggered upon walking. However, in the current context gait disturbance refers to difficulty walking on the basis of a neurological or muscular disease.

Sudden and involuntary contractions of one or more muscles.

A phenomenon whereby patients are not able to stand up without the use of the hands owing to weakness of the proximal muscles of the lower limbs.

Facial nerve palsy is a dysfunction of cranial nerve VII (the facial nerve) that results in inability to control facial muscles on the affected side with weakness of the muscles of facial expression and eye closure. This can either be present in unilateral or bilateral form.

Generalized (diffuse, unlocalized) amyotrophy (muscle atrophy) affecting multiple muscles.

Perceived difficulty to breathe that occurs with exercise or exertion and improves with rest.

An elevation of the level of the enzyme creatine kinase (also known as creatine phosphokinase (CK; EC 2.7.3.2) in the blood. CK levels can be elevated in a number of clinical disorders such as myocardial infarction, rhabdomyolysis, and muscular dystrophy.

The upper eyelid margin is positioned 3 mm or more lower than usual and covers the superior portion of the iris (objective); or, the upper lid margin obscures at least part of the pupil (subjective).

Paralysis of the external ocular muscles.

Progressive external ophthalmoplegia is a condition characterized by weakness of the eye muscles. The condition typically appears in adults between ages 18 and 40 and slowly worsens over time. The first sign of progressive external ophthalmoplegia is typically drooping eyelids (ptosis), which can affect one or both eyelids. As ptosis worsens, affected individuals may use the forehead muscles to try to lift the eyelids, or they may lift up their chin in order to see. Another characteristic feature of progressive external ophthalmoplegia is weakness or paralysis of the muscles that move the eye (ophthalmoplegia). Affected individuals have to turn their head to see in different directions, especially as the ophthalmoplegia worsens. People with progressive external ophthalmoplegia may also have general weakness of the muscles used for movement (myopathy), particularly those in the neck, arms, or legs. The weakness may be especially noticeable during exercise (exercise intolerance). Muscle weakness may also cause difficulty swallowing (dysphagia).\n\nWhen the muscle cells of affected individuals are stained and viewed under a microscope, these cells usually appear abnormal. These abnormal muscle cells contain an excess of cell structures called mitochondria and are known as ragged-red fibers.\n\nProgressive external ophthalmoplegia is part of a spectrum of disorders with overlapping signs and symptoms. Similar disorders include ataxia neuropathy spectrum and Kearns-Sayre syndrome. Like progressive external ophthalmoplegia, the other conditions in this spectrum can involve weakness of the eye muscles. However, these conditions have many additional features not shared by most people with progressive external ophthalmoplegia.\n\nAlthough muscle weakness is the primary symptom of progressive external ophthalmoplegia, this condition can be accompanied by other signs and symptoms. In these instances, the condition is referred to as progressive external ophthalmoplegia plus (PEO+). Additional signs and symptoms can include hearing loss caused by nerve damage in the inner ear (sensorineural hearing loss), weakness and loss of sensation in the limbs due to nerve damage (neuropathy), impaired muscle coordination (ataxia), a pattern of movement abnormalities known as parkinsonism, and depression.