Should I apply hot or cold therapy? There is often confusion following an injury concerning whether to apply cold therapy or whether to warm the area. The answer depends on the type of injury you have sustained.
In general, you can’t go wrong with cold therapy as long as you are aware of contraindications and do not apply it directly to the skin. However, applying heat therapy at the wrong time may be harmful. The choice between heat and ice for sports injuries depends on the type and timing of the injury:
When to apply ice/cold therapy
Ice is generally recommended for acute injuries, which are those that have occurred within the last 48 hours. Cold therapy helps reduce swelling, inflammation, and pain. Ice is effective in the initial stages of a sports injury. For example, sprains, strains, bruises, or acute inflammation.
When to apply heat
Heat is better for chronic conditions. It helps relax and loosen soft tissues and stimulates blood flow to the area. Use heat for muscle pain or stiffness, chronic muscle injuries, and stress-related injuries. Never apply heat immediately after an injury as it can increase swelling and inflammation. It’s important to note that everyone’s body reacts differently, and what works for one person may not work for another.
Hot or cold therapy for acute injuries
Acute injuries are those which result from traumatic incidents, for example, a fall, twisting movement, or direct blow. Acute injuries are immediately painful. When an acute injury first occurs it is important you limit bleeding, inflammation, swelling, and pain as much as possible. Apply ice as soon as possible after injury. This has the following effects:
- Cool the tissues
- Reduces metabolic rate
- Slows nerve conduction velocity
- Causes vasoconstriction of the surrounding blood vessels
Ice should remain in contact for up to 20 minutes at a time depending on the size of the area being treated and the depth of the injured tissues. For example, a finger may only need 5 to 8 minutes, where a large footballers hamstring needs the full 20 mins. Apply cold regularly, every 1-3 hours for the first couple of days.
Hot and cold alternating
Later, once internal bleeding has stopped and there are no signs of inflammation, you may wish to alternate cold and heat treatments. One protocol is to apply cold for 10 minutes, followed immediately by 10 minutes of heat. Doing this causes increases in blood flow to the area as the vasoconstriction caused by cooling reverses when heat is applied. This results in an influx of blood to the damaged tissues. Ensure all bleeding has stopped before applying this technique. Blood is vitally important in providing all of the energy and nutrients that the body needs for repair.
Hot or cold therapy for chronic injuries
Chronic injuries usually do not present as sudden onset. They tend to gradually build up over a period of days, weeks, or longer. The cause is often a combination of overuse and biomechanical abnormality. A chronic injury also occurs following an acute injury that fails to heal due to a lack of, or inappropriate treatment.
Apply heat for 15-20 minutes in the form of hot water bottles, a warm damp towel, heat rub or commercially available heat pads. If using something such as a hot water bottle, ensure a suitable layer of protection is placed over the skin to prevent burns.
In general, heat should be used to treat chronic injuries, to help relax tight, aching muscles and joints, increase the elasticity of ligaments and tendons and increase the blood flow to the area. Heat therapy can also be used prior to exercise in chronic injuries to warm the muscles and increase flexibility.