Sinking legs when walking: First of all, it may be caused by overexertion, such as heavy physical labor for a long time, it may cause the symptoms of lower limb pain and weakness. In addition, it may be caused by viral infection, such as patients suffering from viral cold, in addition to the symptoms of the common cold, during the cold may also appear weakness of the limbs, body aches and pains. Patients suffering from hypothyroidism and other diseases are also prone to symptoms of weakness due to a reduced basal metabolic rate, and may experience sluggishness in the legs when walking. In addition, patients suffering from lower limb vascular diseases, such as varicose veins and phlebitis of the lower limbs, may also have symptoms of sluggishness when walking due to poor venous return of the lower limbs. Therefore, in this case, first of all, we should pay attention to rest and ensure sufficient sleep. In addition, it is necessary to strengthen nutrition appropriately to increase resistance. If accompanied by other symptoms, further examination is also needed to clarify the diagnosis and provide targeted treatment according to the cause.