Decreasing or increasing blood flow
Cold therapy helps with the reduction of inflammation and swelling and tends to cause vasoconstriction—decrease of blood flow—to the area where it is applied. The application of cold sedates irritated nerves, causing a decrease of pain.
Heat is good to use when the injury is characterized by stiffness more than it is characterized by pain. Heat can increases blood flow to a treated area so the cells can begin or continue the healing process. It relaxes muscles by increasing their elasticity and aids the process of breaking up scar tissue/adhesions. It is good to use heat when you have tight muscles and before exercise or strenuous activity.
When you do use heat in the treatment of an injury, it is a good idea to end your therapy session with ice. Heat will increase swelling, ice will decrease swelling!
Application
You can certainly ice with an ice pack, but you can just as easily pull a bag of frozen peas out of the freezer, or use ice cubes wrapped in a towel. ALWAYS use a layer material (t-shirt thickness) between your skin and the cold pack.
Common ways to apply heat are the use of a hot pack or heating pad, or soaking a towel in hot water, wringing it out and wrapping it within a dry towel and then placing or wrapping it on the area, filling a water bottle with hot water, wrapping it in a moist towel and applying it to the area, soaking in a hot tub or allowing a warm shower to spray on an injured area.
How long should I use ice or heat therapy?
Cold therapy can be used as often as possible within the hours after an “acute” injury to reduce inflammation. Just be sure to allow your skin to return to its normal temperature before applying more cold. A common-sense rule of thumb for the application of ice would be 20 minutes on the hour (20 minutes on and 40 minutes off). After the initial day or so has past, continue icing the area at least three times a day. There will be a decrease in the swelling and pain within that first 72 hours after an injury.
The use of ice or heat is also dependent upon the area of thickness. The thicker the muscle and underlying tissue, the longer ice or heat needs to be applied to reach its desired effect (a muscle on the arm can be iced or heated for 15 minutes where as a muscle at the hip should be iced or heated for 20-25 minutes).
The frequency of this type of home therapy can be dependent upon the severity of an injury and the amount of swelling (a mildly strained muscle may only need to be iced and heated for a day, whereas a muscle injured due to a car accident may need to be iced and heated for 3-4 days).
Cautions
In all instances, be aware of these precautions before using either ice or heat. If you have any challenges with neuropathy and don’t feel hot or cold because of your condition, always seek medical advice first.
Ice may be used more freely than heat. Heat has a greater risk of causing pain or burning if used incorrectly. Never put ice or intense heat directly on your skin. Always have a protective barrier between your skin, usually a hand towel or cloth.
If the inflammation, swelling and pain persist, please contact our office, or your chiropractor or primary healthcare physician immediately.
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