cing after injury is a standard practice in sports medicine because it helps to decrease swelling and lessens the extent of an ankle injury. A general rule for the first 24 to 48 hours after injury is to keep ice on it for 30 minutes and then off for 30 minutes. After that, icing is typically only used before, after, and during rehabilitation exercises as well as after any activity. Heat is rarely used on ankle injuries unless you are trying to reduce joint stiffness before activity.