Жаттығуға төзімсіздік және оның түрлері

Exercise intolerance is a condition of inability or decreased ability to perform physical exercise at the normally expected level or duration for people of that age, size, sex, and muscle mass.

Post exertional malaise (PEM) and exercise intolerance are common symptoms of post acute infection syndromes. Post exertional malaise is a worsening of symptoms after minimal physical or mental activity, and is a cardinal symptom of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Both PEM and exercise intolerance are common in long COVID. Orthostatic intolerance (OI) occurs in ME/CFS. OI includes exercise intolerance as one of the main symptoms. It also includes fatigue, nausea, headaches, cognitive problems and visual disturbances as other less major symptoms.

Exercise intolerance is present in those with PCS however their intolerance to exercise may reduce over time. Individuals with postconcussion syndrome may also experience a level of exercise intolerance, however there is little known comparatively about exercise intolerance in PCS patients.

Spinal muscular atrophy: symptoms include exercise intolerance, cognitive impairment and fatigue. Rhabdomyolysis: a condition in which muscle degrades, releasing intracellular muscle content into the blood as reflected by elevated blood levels of creatine kinase. Exercise tolerance is significantly compromised.

Exercise tolerance reflects the combined capacity of components in the oxygen cascade to supply adequate oxygen for ATP resynthesis by oxidative phosphorylation. In individuals with diseases such as cancer, certain therapies can affect one or more components of this cascade and therefore reduce the body's ability to utilise or deliver oxygen, leading to temporary exercise intolerance. Abnormal thyroid function can cause hyperthyroid myopathy and hypothyroid myopathy by affecting myocardial oxygen function. Both include symptoms of muscle fatigue and muscle pain, with dyspnea (shortness of breath) presenting in hyperthyroid myopathy. Thyroxine (T4) deficiency leads to a reduced mitochondrial oxidative capacity, abnormal glycogenolysis and an insulin resistant state of the cell. Hypothyroid myopathy includes Kocher Debre Semelaigne syndrome (childhood onset) and Hoffmann syndrome (adult onset).

Cytochrome b mutations can frequently cause isolated exercise intolerance and myopathy and in some cases multisystem disorders. The mitochondrial respiratory chain complex III catalyses electron transfer to cytochrome c. Complex III is embedded in the inner membrane of the mitochondria and consists of 11 subunits. Cytochrome b is encoded by the mitochondrial DNA which differs from all other subunits which are encoded in the nucleus. Cytochrome b plays a major part in the correct fabrication and function of complex III. This mutation occurred in an 18 year old man who had experienced exercise intolerance for most of his adolescence. Symptoms included extreme fatigue, nausea, a decline in physical activity ability and myalgia.

Individuals with elevated levels of cerebrospinal fluid can experience increased head pain, throbbing, pulsatile tinnitus, nausea and vomiting, faintness and weakness and even loss of consciousness after exercise or exertion.

A person who is not physically fit due to a sedentary lifestyle may find that vigorous exercise is unpleasant.