Cold therapy, using ice packs, gel packs or chemical instant cold packs, can help to reduce inflammation and swelling from injury or exercise.
Cold causes a narrowing (vasoconstriction) of the blood vessels which supply blood to an injured area, which helps prevent swelling. Cold application is most effective in treating injuries when it is used before there is swelling.
Gel cold packs contain a silicate gel which can be cooled or frozen, and which conform to the body.