The heat and ice debate can be confusing. Heat feels good and generally ice does not. Inflammation is what helps decide which to use.
Inflammation is a reaction of the body to injury, characterized by pain, redness, swelling, heat, and sometimes loss of function. Ice constricts the blood vessels around inflammation to decrease blood flow to that area helping to reduce pain, swelling, and redness, and heat. Following an injury, inflammation usually lasts between 24-72 hours. When you use the back of your hand to touch the area of inflammation and you no longer feel heat (note: do not test the area for heat following an application of ice), the inflammatory process is over and it is okay to use an application of heat. Heat opens the blood vessels, increasing blood flow to the area. This increase in blood flow helps the body remove the products of inflammation, loosen up tight muscles, and promote a feeling of general relaxation.
Ice packs, frozen bag of peas, or frozen gel pack are forms of ice applications. Magic Bag, microwavable gel or heat packs, or heating pads can be used to apply heat. A good rule of thumb is applying heat or ice up to 20 minutes and no longer, unless directed by a health professional.
Ice and heat are very helpful in managing the effects of an injury, decreasing the amount of recovery time.