"My back sore! Should I put an ice pack on top or a heating pad?"
It really depends on the nature of the injury causing the pain. Sometimes ice is the best therapy. Other times heat may work better. There is even a thing called contrast therapy where you can blend the benefits of both ice and heat in the same session.
Ice or Heat?
The time to use ice is when you are feeling pain due to inflammation. It may be a sudden inflammatory response from an injury, like a sprained ankle, or it could be the chronic joint inflammation from a disease like arthritis.
Now when most people hear the word "inflammation," the first thing that comes to mind is swelling. Swelling is a part of the inflammation process, but there are other components besides just swelling. These other aspects of inflammation include: heat, redness (due to increased blood flow), and of course, tenderness and pain.
Most of the pain caused by this inflammation response occurs deep in the traumatized tissues of the body. The goal when using ice, or cryotherapy, is to help reduce the whole inflammation process by cooling the area. The specific effects acheived when using ice include:
- Decrease of cellular metabolism
- Decrease of the nerve conduction of pain signals
- Production of enkephalins (your body's own painkilers)
- Thickening of joint fluids and decrease of joint ranges of motion
- Constriction of blood vessels
- Increase of soft tissue stiffness
So in a nutshell, ice slows down the cells' ability to produce pain-causing biochemicals, numbs the sensitivity of the nerves that are sending pain signals to the brain, and accelerates the body production of natural painkillers. On the down side, ice makes the joints and muscles a bit more stiff.
Heat, on the other hand, can be a bit deceptive because it feels soothing while it is on, but the heat therapy may actually be worsening the condition by prolonging the inflammatory process. Heat can be effective in relaxing tight muscle spasms, but only when inflammation and pain is minimal. Here are the specific effects of heat (compare them to ice):
Increase of cellular metabolism
Increase of the nerve conduction of pain signals
Production of enkephalins
Thinning of joint fluids and increase of joint ranges of motion
Dilation of blood vessels
Decrease of soft tissue stiffness
So to break it down, heat actually triggers the cells in the injured area to produce more pain-causing biochemicals and makes the nervous system more sensitive to pain signals. However, heat does increase blood flow which loosens up the joints and softens tight muscles.
The bottom line is to use ice when you want to get rid of pain. Use heat when you want to relax the muscles and joints of the body. When using either ice or heat, the therapy session should never go past 20 minutes.
There are times when you may be willing to take the downsides of both ice and heat at the same time in order to capture the benefits of both. This is when you would use contrast therapy. Start with 15 minutes of ice. After that, immediately apply heat for 15 minutes. After the heat, go back to the ice right away for another 15 minutes. If you respond well to this 45 minute contrast therapy you should feel less localized pain and decreased muscle spasms around the injured area.
So next time you have some pain in the neck, shoulders, lower back-- wherever-- consider ice and heat before reaching for the pills in the medicine cabinet. Sure, popping a tablet is fast and easy, but in my opinion, ice and heat therapies are actually safer and more effective methods of killing pain.
