Exercise Intolerance Is Not a Diagnosis — It’s a Symptom
A comprehensive list of possible illnesses or disorders that can be associated with exercise intolerance, grouped by category: Exercise intolerance refers to an abnormal or reduced response to physical activity — often presenting as excessive fatigue, breathlessness, weakness, or muscle pain — that exceeds what would be expected for an individual's age, fitness level, or health status. It is not a diagnosis in itself , but a clinical sign pointing to a wide range of possible underlying conditions. These can span cardiovascular, respiratory, neuromuscular, metabolic, genetic, infectious, or systemic causes. Focus: The list below groups these potential causes by underlying pathophysiology or origin (e.g., genetic, viral, bacterial, etc.), and highlights whether the central nervous system (CNS) is involved. Note: Psychological or functional causes, including Somatic Symptom Disorder (SSD), have been intentionally excluded due to the lack of objective evidence. Cardiovascular ...