1, avoid strenuous exercise. Strong muscle exercise obviously affects the body’s metabolism, causing changes in the concentration of certain components in the blood, such as lactic acid, CK, AST, LD, ALP and other elevated, so it is generally advocated not to do strenuous exercise within 24 hours before blood sampling. Take blood early in the morning, inpatients can take blood before waking up, and those who rush to the outpatient clinic should take blood after at least 15 minutes of rest. 2. Pay attention to a reasonable diet. Except for emergency or other special reasons, it is generally advocated to take blood after 3 days of normal diet, and overeating and deliberate diet control should be avoided. Blood should be collected in the early morning of the next day after 10-14 hours of fasting. Postprandial or extended fasting time (starvation) can cause changes in the chemical composition of blood. Postprandial glucose, potassium, alkaline phosphatase and triglycerides usually increase, and inorganic phosphorus decreases; when starving, glucose and protein decrease, and bilirubin increases; in addition, the quantity and quality of the diet also have an effect on the test results, such as high protein diet can make serum urea nitrogen, blood ammonia and uric acid increase; high fat diet causes celiac disease, resulting in serum lipemia (cloudy); drinking too much or too little water can make serum dilution or concentration; drinks containing Caffeinated beverages can cause the release of catecholamines, etc. 3, the impact of alcohol consumption. Immediately after drinking alcohol, serum lactic acid and uric acid rise; continuous drinking causes AST and ALT to rise, while GGT rises most significantly. Long-term drinkers tend to have hypertriglyceridemia, and GGT will also be abnormal for a long time. 4, emotional impact. Avoid tension and emotional excitement, which can otherwise affect neuro-endocrine function test items. Shortness of breath can raise serum lactate, etc. 5, drug influence. Many drugs into the body can make certain laboratory test results higher or lower, such as caffeine can make blood sugar and cholesterol higher; coronary heart can make triglycerides and lactate dehydrogenase lower; vitamin C can make lactate dehydrogenase lower; oral contraceptives can make transaminases higher, etc.. Therefore, patients should stop taking drugs that interfere with the test as much as possible before the test. 6, the impact of the position when taking blood. Position (standing, sitting, lying) changes can cause significant changes in some laboratory indicators, so it is recommended that the blood should be taken after 5 minutes in the sitting position.