Cryotherapy is the targeted use of cold to effect a therapeutic effect. The local application of freezing techniques is differentiated from the generalized cold treatment of the whole body.
In the case of complaints of inflammation or injury (for example during sports: strains, bruises, sprains of the back), cold therapy is a sensible way of quickly relieving pain. Applications can be e.g. with ice, gel compresses and cold compresses.
Source: Wikipedia