A common question that we are often asked in clinic is whether ice or heat is apppropriate to use on an injury and if so, which. In this blog we will outline the rational behind choosing ice or heat and give some common clinical examples.

When ice is placed on an area it causes constriction or narrowing of blood vessels. This in turn, leads to a reduction in swelling and inflammation because a constricted blood vessel allows less leaking of fluid and inflammatory chemicals through the wall of the blood vessel into the surrounding tissues. In an acute injury (e.g. ankle sprain/ ligament injury to knee), where there is a risk of swelling, the injured part will benefit from ice. You can use a packet of frozen peas wrapped in a damp tea towel or an ice pack for ten minutes at a time. Ten minutes is sufficient to allow the tissues to reduce in temperature and the blood vessels to constrict. Be careful with ice, too long can cause frostbite!

Heat has the opposite effect to ice. Heat causes blood vessels to dilate or get larger, allowing more blood flow into the area and even more importantly, muscle relaxation. Heat is useful for more chronic conditions that are due to overuse, such as a muscular ache around the top of the back and shoulders from prolonged sitting at a computer in a poor position. In fact heat is often helpful for back pain, particularly when there is muscle spasm present. When muscle spasm is present as a symptom of back pain, the continuous contraction of the muscle in spasm starts to generate pain in its own right. Reducing that spasm (e.g with heat) can help with the pain. You could use a towel or facecloth soaked in warm water or a hot water bottle/ hot pack (warm, not hot.) Never put heat on an acute injury (such as an ankle sprain) as it will make the swelling worse. Think of what happens to your feet on a warm day- they swell and are more difficulty to get into your shoes.

Applying ice or heat is a first aid measure and a step towards recovery. However it is important to receive appropriate advice and treatment for your injury in order that you make a full recovery. Contact IONA Physiotherapy if you have had an injury, we would be delighted to help.

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