Heat vs Ice Info
Reviewed by Dr Kieran Hirpara, Specialist Orthopaedic Surgeon Last reviewed
After an injury or operation, "should I use heat or ice?" is one of the most common questions we get asked. The short answer is ice for swelling, heat for stiffness, but the timing matters more than the choice.
Ice — for the first few days
Ice is most useful in the first 48 to 72 hours after a fresh injury or after surgery. It works by narrowing the blood vessels under the skin, which slows the inflammatory response and reduces swelling and pain.
How to use it well:
- 15 to 20 minutes at a time, no longer
- Always wrap the ice pack in a tea towel; never put ice directly on skin
- In the first week after surgery, icing every hour or so is fine if it helps; after the first few days, three or four times a day is usually enough
- Stop if the skin goes numb, white, or bright red
A bag of frozen peas wrapped in a towel works as well as any purpose-bought ice pack. Cheap and reusable.
Heat — once the swelling has settled
Heat helps stiff, aching muscles and joints, but it makes acute swelling worse. Switch from ice to heat once the early swelling has settled: for many operations that happens during the first week or two, and your therapist will guide the change. While the limb is still swollen, stay with ice. The exception is surgery done to release a stiff joint (capsular release, arthrolysis): there, heat before stretching is encouraged from the start.
How to use it well:
- A wheat bag heated in the microwave, a hot water bottle, or a warm shower all work well
- 20 minutes at a time
- Don't sleep with a hot pack on; burns happen when the skin is pressed against a heat source for hours
Heat is especially helpful before exercises or physiotherapy sessions: it loosens stiff tissue so you can stretch further with less discomfort.
When neither helps
If your pain is getting worse rather than better, or if the limb is red, hot, increasingly swollen, or starting to look different from the other side, that's not a heat-or-ice question: call your treating clinician.
Quick rule of thumb
| Stage | What it feels like | Use |
|---|---|---|
| First 2-3 days | Throbbing, tight, swollen | Ice |
| Week 1-2 | Settling but stiff | Either, follow your therapist's lead |
| Week 2 onwards | Stiff but not swollen | Heat before exercises, ice after if sore |
| Anytime | Sharp pain that wasn't there before | Phone, not packs |
