Physical activity is any bodily movement produced by skeletal muscles that requires energy expenditure above resting levels. Physical fitness refers to the ability to perform physical activities without undue fatigue and is achieved through a combination of proper nutrition, regular moderate-to-vigorous physical activity, and adequate rest.

Obesity is a chronic, relapsing, multifactorial disease characterized by excessive accumulation of body fat that adversely affects health. It is associated with increased morbidity and mortality through its effects on the cardiovascular, endocrine, respiratory, musculoskeletal, and gastrointestinal systems

Disorders of sexual development (DSDs), formerly known as intersex conditions, are a group of congenital conditions in which the development of chromosomal, gonadal, or anatomical sex is atypical. They are classified according to genetic characteristics and gonadal development and may result from virilization of individuals with a 46,XX karyotype, undervirilization of individuals with a 46,XY karyotype, or disorders of gonadal development such as mosaicism, streak ovary, ovotestis, or dysgenetic testes.

Pheochromocytoma is a rare neuroendocrine tumour arising from catecholamine-producing chromaffin cells of the adrenal medulla. Approximately 15–20% of these tumours originate outside the adrenal glands (extra-adrenal), where they are commonly referred to as paragangliomas.

Diabetic insipidus (DI) is a disorder of water balance characterized by the inability to concentrate urine, resulting in the excretion of large volumes of dilute urine. It is caused by non-osmotic renal loss of water and may lead to dehydration, hypernatremia, and disturbances in fluid and electrolyte balance if untreated. Diabetes insipidus is distinct from diabetes mellitus, as it is not related to abnormalities in blood glucose metabolism but rather to deficiencies in antidiuretic hormone (ADH) secretion or action.