Weakness and weakness of legs and feeling especially tired may be caused by physiological or pathological reasons, such as exertion, hypoglycemia, anemia, hypokalemic periodic paralysis, lumbar spine disease, etc. It is necessary to clarify the causes and then treat them through rest, medication, surgery and other treatments. 1. Physiological reasons: after a lot of activities during the daytime, the body’s energy consumption is too large, and you may feel that your legs are sore and weak, and you feel especially tired. This condition generally does not require special treatment and can be relieved after rest. 2. Pathological causes (1) Hypoglycemia: patients may have symptoms such as cold sweat and weakness of legs, which can be relieved by eating foods with high sugar content, such as candies and drinks. If the symptoms are serious, it is necessary to consult a doctor in time. (2) Anemia: Due to the decrease of oxygen content in the blood, you may also feel weak and tired. The cause of anemia needs to be clarified and treated according to the cause. For example, iron deficiency anemia needs to be supplemented appropriately. (3) Hypokalemic periodic paralysis: Due to the obvious decrease of potassium ions in the body, patients may feel weak and tired. Prompt medical consultation is needed to give potassium supplementation treatment and closely monitor the blood potassium level. (4) Lumbar spine disease: due to the compression of nerve roots, patients will feel weak and tired. Conservative treatment or surgery is needed for the primary disease. If there is persistent weakness and tiredness in the legs, patients should consult the doctor in time to clarify the cause of the disease and then follow the doctor’s instructions for treatment.