Ice therapy can be used on acute injuries, meaning a recent injury that has caused swelling, pain and/or redness. Acute injuries usually will result from a sudden fall or trauma such as an ankle sprain. The ice helps to constrict the blood vessels around the injury, which cuts down the blood supply, helping to reduce the swelling and pain. It may be used on chronic injuries that cause swelling to occur in or around a joint as well.
Heat therapy can be used on more chronic injuries or injuries where no swelling is present. Examples of when to use heat would be with sore or tight muscles. Heat can help relax muscle spasms by bringing blood ow to the area. Either treatment can be applied for 15-20 minutes at a time, but be sure to remove after 20 minutes.