Heat and cold therapy are often recommended to help relieve an aching pain that results from muscle or joint damage. Basic heat therapy, or thermotherapy involves using of a hot water bottle, steam, pads that can be heated in a microwave, or a warm bath. For cold therapy, or cryotherapy, a water bottle filled with cold water, a pad cooled in the freezer, or direct cold water can be used. In some cases, your treating physiotherapist may decide to apply alternating heat and cold to better manage the injury.
Applying heat to an inflamed area will dilate the blood vessels, promote blood flow, and help relax the sore and tightened muscles. Improved circulation can help eliminate the build-up of lactic acid waste that occurs after some types of exercise. Heat therapy is usually more effective than cold at treating chronic muscle pain or sore joints caused by arthritis. Heat is normally applied to the area for 20 minutes, up to three times a day, unless otherwise indicated.
Types of heat therapy include
Heat is useful for relieving
Heat should not be used if
Cold treatment reduces blood flow to an injured area. This slows the rate of inflammation and reduces the risk of swelling and tissue damage. It also numbs sore tissues, acting as a local anaesthetic, and slows down the pain messages being transmitted to the brain. It is most effective within 48 hours of an injury, especially where heat is being generated.
Some ways of using cold therapy include
Cold treatment can help in cases of
Cold is not suitable if
When cold is applied to the body, the blood vessels contract, vasoconstriction occurs. This means that circulation is reduced, and pain decreases. Removing the cold causes vasodilation, as the veins expand to overcompensate. As the blood vessels expand, circulation improves, and the incoming flow of blood brings nutrients to help the injured tissues heal.
Alternating heat and cold can be useful for:
Your therapist will select heat or cold (or an alternating combination) based on your specific condition and its stage, and monitor the application to keep it safe and comfortable — this is often paired with other treatments in the same session.
As a general rule, cold suits fresh injuries and active swelling, while heat suits chronic stiffness and muscle tightness — but ask your therapist for guidance specific to your condition.
Yes, your therapist can advise on safe home use, including duration and precautions, to support your in-clinic treatment.
Yes — alternating heat and cold (contrast therapy) is sometimes used specifically to promote circulation, and your therapist will advise if this suits your condition.
Extra caution is needed, since reduced sensation can increase the risk of burns or skin damage; your therapist will take this into account and adjust the approach accordingly.
Duration is based on your specific condition, the stage of healing, and your skin’s response, and is monitored throughout to keep it both safe and effective.
