As a general rule, use ice for pain in the first couple of days after a new injury, and heat for stiffness, muscle tightness and aches that have been around longer. Both mainly relieve symptoms. Neither heals the injury, so use whichever makes you more comfortable while you keep moving.
When ice makes sense
- A fresh sprain, strain or knock, especially with swelling
- Pain flaring up after activity
- When numbing the area helps you sleep or move
How: wrap an ice pack or bag of frozen peas in a thin, damp cloth and apply for 10 to 15 minutes. Wait at least an hour before repeating.
When heat makes sense
- Stiff joints or tight muscles, such as a stiff low back or neck
- Aches that have lasted more than a few days, with no fresh swelling
- Before stretching or gentle exercise, to help you loosen up
How: use a warm (not hot) pack or wheat bag with a layer of cloth for 15 to 20 minutes, or take a warm shower or bath.
When to avoid each
- Avoid heat on a new injury that is swollen, hot or bruising, and on any area that is red or infected
- Avoid ice if you have poor circulation or a cold sensitivity condition such as Raynaud’s
- Avoid both on skin with reduced feeling, over open wounds, and never fall asleep on a hot or cold pack
- If you have diabetes or nerve damage, ask your health professional first
What matters more than heat or ice
Protect a new injury from further damage for the first few days, then start moving it gently and build activity back up as pain allows. Long periods of complete rest tend to slow recovery. A physiotherapist or chiropractor can tell you how much to do and when.
When to get it looked at
- You cannot bear weight or use the limb
- There is obvious deformity, or numbness or tingling that does not pass
- Severe swelling or bruising appears quickly
- Pain is not improving after a few days
- A calf is hot, swollen and painful, or you have a fever: see a doctor promptly
Related: when should I see a physiotherapist for a sprained ankle? and can I keep training while injured? More detail is on our physiotherapy page.
Not sure what your injury needs?