to rehabilitation or performance because of its known adverse effects to performance such as decreased myotatic reflex and force production, as well as a decrease in balance immediately following ice pack therapy for 20 minutes. However, if ice pack therapy is applied for less than 10 minutes, performance can occur without detrimental effects. If the ice pack is removed at this time, athletes are sent back to training or competition directly with no decrease in performance. Ice has also been shown to possibly slow and impair muscle protein synthesis and repair in recreational athletes. This is especially true for cold water immersion, but equivalent controlled studies have not been done to see if the same effects hold true for ice packs. Regardless, ice has been shown in studies to inhibit the uptake of dietary protein post-muscle conditioning exercise. Cryotherapy following total knee replacement Total knee arthroplasty (TKA) is a common intervention for patients with end-stage osteoarthritis of the knee. Post-surgical management includes cryotherapy. Cryotherapy may slightly reduce the amount of blood loss and pain. It was generally safe and not associated with any serious adverse events. It may improve the range of movement at the knee in the first one to two weeks after surgery. Potential benefits of cryotherapy on blood loss, postoperative pain, and range of motion may be too small to justify its use, and the quality of the evidence was very low or low for all main outcomes. Well designed randomized trials are required to improve the quality of the evidence. In conclusion, the effectiveness of cryotherapy is unclear. Cold spray anesthetics In addition to their use in cryosurgery, several types of cold aerosol sprays are used for short-term pain relief. Unlike other cold modalities, it doesn’t produce similar physiological effects due to the fact it decreases skin temperature, not muscle temperature. It reflexively inhibits underling muscle by using evaporation to cool the area. Ordinary spray cans containing tetrafluoroethane, dimethyl ether, or similar substances, are used to numb the skin prior to or possibly in place of local anesthetic injections, and prior to other needles, small incisions, sutures, and so on. Other products containing chloroethane are used to ease sports injuries, similar to ice pack therapy. Whole body cryotherapy An increasing amount of research is done on the effects of whole-body cryotherapy (WBC) on exercise, beauty, and health. Research is often inconsistent because the usage of the