An article by exercise physiologist, Jennifer Smallridge
When it comes to soft tissue injuries (muscles, tendons and ligaments) or general aches and pains, you may have reached for the frozen peas or the heat pack, depending on where you are, what you’ve heard and what your body has responded to previously.
But which one is best?
Anything that provides passive cooling (ice packs, ice baths, frozen peas, frozen water bottles) creates vasoconstriction. This means that the blood vessels become more narrow, slowing down the flow of blood to the injured area.
If you have a significant joint sprain (eg: rolled ankle), muscle strain (eg: torn hamstring) or are likely to bruise after a big impact, cold therapy can be great to reduce swelling and inflammation. Take care not to apply ice directly to the skin as this can damage the upper layers. A general rule for application is 20 minutes, every two hours, starting straight after the injury and ceasing after a few days. Ice is best used with rest, compression and elevation - creating the acronym RICE.
It is worth noting that if your sprain or strain is minor, and swelling isn’t looking evident, then it is best to let the body’s own inbuilt inflammatory process do its job and heal.
It is likely that you have some form of heat therapy tool in your home - be it a hot water bottle or wheat bag for the microwave. A hot shower or bath also counts as heat therapy. But when should you use it?
Firstly, as mentioned above, if there is a lot of acute (new) swelling and inflammation in the area - do not apply heat as this can prolong the pain and enlargement.
But if you have persistent pain, or an ongoing joint niggle, or an occasional ache, heat therapies are wonderful for opening up the blood vessels and promoting blood flow to the affected area. If you did first utilise cold therapy, then heat is a very appropriate pain management tool 72 hours after the injury.
Heat therapy does not mean that you should feel a burning sensation - rather, it should be pleasant and comfortable. Heat is also effective for people with muscle tension and stiffness, particularly before physical activity (much like a warm up works for the whole body, but passive heating can target particular areas). Some people also experiment with alternating heat and cold therapy, although research in this area is limited.
Ice is indicated for acute injuries within the first 72 hours, if the swelling caused by the injury is deemed significant and likely to impede the healing process. Consult with a doctor if you are unsure, or if you suspect a fracture.
Heat is best for injuries after the first 72 hours, as well as ongoing aches and pains to promote blood flow and keep you active.