Ice is very important for sports injuries and is one of the essential treatment modalities. In clinical work, it is found that patients generally do not know what is the scientific method of icing, so here to tell you. First of all, the principles of icing are: reducing and slowing down the release of histamine, reducing tissue sensitivity to pain; reducing microcirculation and surrounding tissue exudation and swelling; reducing the action of vascular endothelial cells and thrombosis; reducing the release of oxygen free radicals, etc. There are also many studies that show that microcirculatory disorders and the tissue damage response secondary to them are not evident within the first 24 hours after trauma. Therefore, icing should be applied as early as possible and should be continued for a period of time. In this way, early and reasonable icing can achieve the purpose of reducing the degree of tissue trauma and accelerating tissue repair. So what should be done with ice? 1.Part: the part where the pain or swelling occurs 2.Materials: ice and water mixture is the best (I love to describe it to the patient like the “ice drink” sold in KFC), followed by, for example, ice sticks, chemical ice bags, cold water, etc. 3, time: generally 20-30 minutes each time. (This is generally the time required for the ice to melt off) 4, frequency: every 3-4 hours is a common method. 5, the course of treatment: generally used within 48-36 hours after the injury. (This is the general traumatic inflammatory effect of the basic elimination of time).