One of the most common questions I am asked by patients is whether they should use ice or heat on an injury. Both heat and ice improve healing by manipulating blood flow, reducing inflammation, and reducing pain. Knowing which one to use when, though, will keep you from possibly doing further damage.
Ice should be used on acute injuries (injuries that have occurred within the last 72 hours.) Its aim is to limit the body’s response to the injury. It does this by reducing further bleeding into the injured tissues, preventing or reducing swelling, and reducing muscle spasm and pain. Ice should also be used for chronic conditions (arthritis, tendonitis, overuse injuries in athletes), but after activity.
How to Apply Ice
There are several methods for icing an injury. The first uses an ice pack. Place a thin layer of cloth over the injury, to avoid frostbite. Place the ice pack over the cloth. Do not leave the ice on for more than 20 minutes, or you can do more harm than good. Another method of icing is ice massage. Freeze a paper or Styrofoam cup full of water, and then tear off the top rim to expose the ice. Move the ice continuously over the injury for 15 minutes. Ideally, ice on an acute injury should be applied every 2-3 hours.
Heat should be used for chronic injuries to relax and loosen the tissues and stimulate blood flow to the area. Heat should be used before activities, not after. Do not use heat after an acute injury. It will increase inflammation and make the problem worse.
How to Apply Heat
Moist hot towels are the most effective form of heat treatment. They are more effective because the moisture keeps the area from drying out and becoming brittle. Place a washcloth under hot tap water, or heat it up slightly in the microwave, and then apply it directly to the injured area. Heating pads will also work, as well as hot water bottles and soaking in a hot bath. Do not apply for more than 20 minutes at a time. Never fall asleep on a heating pad, and do not apply body weight to the heating pad (do not sit or lie on it.
48-72 hours after an injury, you can also use combination therapy to get the most benefit from both heat and ice. To do this, alternate hot and cold packs for 10 minutes each. By alternating, you keep the swelling under check with the ice, and keep blood and its nutrients circulating through the area with the heat. Be sure to always end with ice, so that the heat does not contribute to further swelling.