The question often comes up as to when it is best to use cold or hot treatment in injuries. When to use ice or heat depends on how long ago the injury occurred.
After you strain a ligament or muscle, it is generally best to use cold (ice or a cold pack) immediately and then for the next day and 1/2. It’s usually wise not to use heat, such as a heating pad, until swelling and bruising has stopped.
Cold is usually used first because it reduces swelling and inflammation. Use Ice for the first 48 hours after an injury. Apply for 20 minutes, remove for 20 minutes, then repeat. Do not apply directly to the skin — put a thin towel over the skin for protection. This helps control bleeding by constricting blood vessels. Cold acts as a local anesthetic and so relieves pain. Usually the bruising associated with acute inflammation stops within 1 to 3 days. To relieve muscle spasms, minor sprains and strains, it’s usually best to apply cold for 20 minutes intervals at a time every 4 to 6 hours for the first day and a half. Commercial cold packs may be safer than using ice. Prolonged exposure to cold, especially ice, can result in frostbite to tissues. Later in the process, you may relieve pain by applying heat, rather than cold, to your injury.
Use heat 20 minutes at a time at least 24 hours after a minor injury or 48 hours after a more serious one. Place a heat pack directly on the injured area — do not add pressure. Do not apply to broken skin.
Cold reduces inflammation. Apply cold to acute injuries, such as a newly sprained ankle or a pulled muscle.
Heat improves circulation. It’s best for chronic pain, such as from tight muscles or a sore back.
Alternate Heat and Cold if you have soft tissue damage and/or stretched ligaments, such as an ankle sprain. Heat aids in restoring range of motion. Apply cold for 20 minutes per hour as desired for the first 24 hours. The next day, apply warmth for 20 minutes per hour as desired.
Caution: Don’t apply cold for more that 24 to 36 hours or warmth for more than 72 hours, see a doctor.