Heat and Ice

Physiotherapists are often asked whether ice or heat is the best choice of treatment.


Ice therapy decreases local inflammation, swelling and bleeding to the area. It also relieves pain. These properties make it very useful for treating acute strains, contusions and swelling.


Heat is also a useful pain reliever. It works by increasing local blood flow. This makes it unsuitable in the first 48 hours of an acute in- jury when bleeding and swelling may be occurring. Heat reduces muscle spasm and chronic pain and is best left for subacute and chronic injuries.

Your physiotherapist will direct you on the application of either ICE or HEAT.

Ice Therapy

What does ice actually do?

Ice is a clinically proven aid for most musculoskeletal injuries, during initial care and later rehabilitation. Ice will promote stronger healing, ease pain and improve recovery time.

Will ice help the pain?

Yes, ice provides strong pain relief. Ice reduces nerve transmission from painful areas. With 4-5 minutes of ice there is sensory fibre analgesia comparable to local anaesthesia.

How do you apply ice?

For the average adult, apply the ice pack to the injured area for 10-20 minutes MAXIMUM with a MINIMUM 20-30 min rest between applications. Early application is important. Depending on the severity of the injury this process can be repeated over a 24-48 hour period or until directed by your physiotherapist.

Ice Sources:

Best is crushed ice, otherwise commercial ice packs. Frozen peas are the least effective.

NOTE: Always place a light wet towel between the skin and the ice pack to avoid the possibility of an ice burn. Never allow your skin to go white from ice application.

How does cold therapy improve recovery time?

The body reacts to injury by initiating an inflammatory response. This increases the permeability of blood vessels, activates local pain receptors and attracts immune chemicals creating swelling. This excess of fluids separates healthy cells in the vicinity from their oxygen source. As a result many healthy cells die from secondary tissue dam- age called “hypoxic injury”. The appropriate application of an ice pack will reduce the destruction of the healthy cells in the injured area.

Ice precautions:

Do not use on infants. Young children should be supervised. Any cold product may cause ice burning if improperly used. Do not use ice before sporting activities as it can lower the areas proprioception. People with circulatory disorders should not use ice/cold therapy.

Heat Therapy

What does heat actually do?

Heat will increase blood flow to an area, soothe and relax muscles in spasm and enhance healing.

Will heat help the pain?

Yes, heat provides mild pain relief by acting as a counter irritant “filling” the nerves with the sensation of heat instead of pain, thereby reducing the amount of pain perceived.

What are some common uses of heat?

  • Relieving pain and stiffness in joints and muscles
  • Relieving stress and tension therapeutically
  • Relieving arthritic pain and stiffness
  • Alleviating stomach cramps and period pain

How does heat improve recovery time?

Heat encourages blood flow to an area, bringing blood, oxygen and nutrients while decreasing inflammation and taking away toxins. All of which considerably speed recovery time.

Heat Precautions

NEVER apply heat to bruises or muscle and joint sprains and strains in the first 48 hours. Heat may increase any local bleeding. If in doubt consult your physiotherapist. Persons with diabetes, circulatory problems, nerve damage, paralysis or sensitive skin should not use heat except if directed by a health practitioner. When pregnant do not apply heat to the abdomen. Do not apply heat where a clot or thrombosis is suspected