One of the most common questions we get asked as Physiotherapists is "Should I Ice or Heat?"
To explain this it helps by understanding the body’s natural repair processes. Once an injury occurs, the repair process has three phases. The first phase clears the damaged cells, the second brings in the cells to form the repair structure, and the third does the finish work to give the cells the final structure and strength. In the case of a muscle tear, the damaged muscle tissue has to be removed, new cells moved in, and then transformed into muscle tissue. Excessive swelling and inflammation from damaged tissue inhibits and slows this process. In the face of an acute injury, like a muscle tear or ligament sprain, ice works to keep the swelling down, which allows the injured parts to stay physically close in the repair process, promoting better healing? Heat, on the other hand, encourages blood flow and increases swelling in the acute phase. So, immediately following injury, heat actually harms the healing process.
It is usually advised to ice for two to three days post injury but this could extend for longer periods depending on the degree of inflammation. A reasonable cycle for icing an injury is 15-20 minutes every couple of hours.
Heat does have a place in chronic injury and after the acute phase of injury – it can relieve pain and relax muscles providing there is no inflammatory process occurring.
A simple couple of great acronyms to remember with acute injuries are:
RICE (Rest, Ice, Compression, Elevation) to reduce blood flow and inflammation to the injured area and do not HARM (Heat, Alcohol, Run, Massage) which will increase bleeding in the tissues.