Ice therapy is most effective if it is applied as soon as possible after the injury occurs, usually within 24 to 48 hours. The cold makes the veins in the tissues contract, reducing circulation. Once the cold is removed, the veins overcompensate and dilate and blood rushes into the area. The infusion of blood in the area brings with it the necessary nutrients to help the injured back muscles, ligaments and tendons to heal.
While any form of applying cold to the injured area – such as a bag of ice wrapped in a towel or a commercial ice pack – should be helpful, combining interferential current therapy with ice application is a nice alternative for pain relief.