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: reduce and slow down the release of histamine, reduce tissue sensitivity to pain; reduce microcirculation and surrounding tissue exudation and swelling; reduce the role of vascular endothelial cells and thrombus formation; reduce the release of oxygen free radicals, etc. There are also many studies showing that the microcirculatory disorder and the tissue damage response secondary to it are not obvious within the first 24 hours after trauma. Therefore, ice should be applied as early as possible and should be continued for some time. In this way, early and reasonable icing can achieve the purpose of reducing the degree of tissue trauma and accelerating tissue repair. So how to do ice? I’d like to introduce to you: 1.Part: the part where the pain or swelling occurs; 2.Material: 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, popsicles, 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, course of treatment: generally used within 48-36 hours after the injury. (This is the time it takes for the general traumatic inflammatory effect to be largely eliminated)