There are four reasons for the weakness and fatigue of the elderly: first, malnutrition absorption and digestion, the elderly do not eat enough, insufficient calorie intake, vitamin and trace element deficiency, the body protein is in negative nitrogen balance, the body albumin and total protein level is too low, so there will be weakness and fatigue and other malnutrition. Second, the elderly are weak, weakness, heart supply is not the main pathogenic factors, such as coronary atherosclerotic heart disease, angina pectoris, pulmonary heart disease and other conditions, resulting in myocardial insufficiency, chronic heart failure, heart failure and induced weakness, weakness of the body. Third, cerebrovascular diseases, elderly people with weakness with dizziness, often have cerebral infarction, cerebral hemorrhage sequelae, triggering weakness and muscle atrophy. Fourth, the elderly have endocrine diseases, periodic hypokalemia, will also have weakness and weakness.