Ask the Therapist: Heat or Ice?
By JD Fields, DPT
AZOPT Goodyear Physical Therapist

Heat or ice?  It’s one of the most common questions we receive.  While it is difficult to generalize all pain and injuries, there are a few simple rules that you can follow to help in your recovery.

Ice is most appropriate for initial (or acute) stages of an injury.  Ice helps control pain levels and constricts the blood flow to areas around the injury.  This decreases the amount of particles that promote inflammation at the site of the issue.   Inflammation is an important part of the healing process initially, but can be more damaging if it continues to linger.  During the first 21 days after an injury, icing is usually appropriate to promote healing.  Try icing for 10 to 20 minutes (or until the area is numb). You can ice multiple times during the day, especially early on in the healing process.  If you have any issues with cold sensitivity or have decreased sensation in the painful/swollen area, ice may not be a good choice due to possible side effects.  If you notice any irritation to the skin that lasts for longer than expected or increases your pain, stop using cold immediately.   Ice during later stages of healing may actually hinder the healing process because it constricts the blood flow to tissues in need.   Instead of icing, appropriate exercise and movement are ways to control swelling once this initial stage has ended.

Heat becomes more appropriate once the acute stage of the injury has passed (sub-acute or chronic).  Heat is used to help promote increased blood flow and decrease pain levels to areas with pain or irritation.  Despite not reaching very deep, heat has mechanisms that can reduce painful stimulus, and heat allows for relaxation that can further assist with pain and improved motion.  Try heat for 10 to 20 minutes depending on your comfort level.  The same precautions for ice apply to heat as well.  If you have any sensation issues or notice any redness or large amounts of swelling in the area, heat should not be used.  Heat during the initial stage of an injury, like in the case of a strained muscle, can cause increased swelling which can create further damage to the healing of tissues.

In cases of longstanding pain, such as low back or neck pain, we can disregard everything that was previously stated.  These chronic types of pain are not related to a specific injury or event.  They seem to start out of thin air.  In these cases, there is no real structural damage or inflammation at the site of pain.  Therefore, it is safe and appropriate to try heat and/or ice to see which provides the most relief.

At the right time, heat and ice will both allow for pain relief.  Also, in the right situation they can help injured tissues heal allowing you to recover quickly to your normal self.