Whether and when to use ice or heat depends on many variables. It depends on whether you have an injury less or more than 48 hours old. It depends on the joint(s) in question – is it for your back or your knee? It depends on how you typically like or respond to either application. Do you have chronic pain, arthritic pain, or a recently pulled muscle? Mostly it depends on what has worked better for you in the past, especially if we’re talking upper back pain, neck pain or chronic low back pain. It can even depend on the season of year.
Having said that, the Official Rules are: Within the first 48 hours of injury, if there is no bleeding, RICE = Rest, Ice, Compression and Elevation of the body part. After 48 hours, apply heat.
In reality you can choose either after 48 hours.
But what if there is inflammation? Anyway, what is inflammation? I like what WebMD has to say about inflammation:
When inflammation occurs, chemicals from the body’s white blood cells released into the blood or affected tissues to protect your body from foreign substances. This release of chemicals increases the blood flow to the area of injury or infection, and may result in redness and warmth. Some of the chemicals cause a leak of fluid into the tissues, resulting in swelling.
A couple of other things to keep in mind. Arthritic joints tend to prefer heat, especially in the winter. Hands too. I mostly suggest heat for neck pain and lower back pain. But some people prefer cold packs. Go with that.
Chinese medicine most always recommends heat.
In general, knees tend to do better with ice, especially after surgery or a TKR (total knee replacement). But if your joints are aging or arthritic, your knees might like a bit of soothing warmth better, especially in the winter.
In practice, I’ve found that shoulders do well with heat and ice. If the shoulder or arm pain is coming from your neck, you likely have cervical radiculopathy or cervical radiculitis. In this case, heat might be the preferred modality.
I usually ask people for their preferences. Do you usually use ice or heat on your low back pain? What works better for you? Then we take it from there.
You can also alternate ice and heat for short intervals. It’s called contrast therapy.
Except for the 48-hour rule, there’s room to experiment. So we’re back to where we started: the answer is . . . it depends.