The Cold Hard Truth About Ice and Cryotherapy

When someone hurts themselves, one of the most common first things they reach for is a bag of ice, a cold compress, or a bag of peas. In fancy terms, they apply a treatment of cryotherapy. 

Why do injured areas get inflamed and stiff?

Ice feels good when you apply it to an injury that is going through an acute inflammatory process. The body is sending a lot of blood and nutrients to the area to respond to the stress that the injury imparted on the area. Once there, the blood and nutrients get to work rapidly to start the repair process, abate any localized bleeding that might be occurring, and generate swelling around the joint, which acts to form an internal splint in order to reduce the range of motion that a joint goes through. 

Do you find that if you have injured a joint, and it gets swollen, that you can’t do these two things:

  • Put weight through it or apply a load through the joint?  There is extra fluid inside the joint. When used, the increased volume of fluid inside the joint that the joint capsule (the skin around the joint) has to contain creates pressure.  When the joint has a load going through it, the pressures inside the joint, and the nerves in the joint capsule and joint nociceptors (pain sensors) get stimulated and then there is a pain signal that goes to the brain.  So, what do you do?  Unload or not use the joint due to pain.
  • Use a joint using its full range of motion?  With all kinds of blood and nutrients that are going to the area that is injured, the body forms a soft splint in the area which will restrict the joints ability to move freely through their full range of motion.

How does icing an area work?

I guess the next question is, what exactly does applying cryotherapy to an inflammed area do?  It causes an intense constriction of the blood vessels coming to (arteries) and leaving (veins) an area.  When you apply it long enough (as you will read below) then you will confuse the brain into thinking that this is the new “norm”.  However, when the ice is removed there is a progressive flushing of the area by blood coming into it. Have you ever noticed that the area you are icing gets really red after you take off the ice?  That is your body’s way of flushing all of the metabolic byproducts from the injury and the inflammatory process out of the area.

It is totally understandable that people reach for the ice.  But are they using it to its full advantage?  Most people aren’t, because they don’t understand how to use ice properly, how often to do it, and for how long but I'll explain it for you below.

How to ice properly.

There are two main ways to apply ice to an area or perform what we call cryotherapy, the static application and the dynamic application.

The static application is what most people do.  Put ice on there, and let it sit there.  The dynamic way is that you move the ice around and perform an “ice massage”.  

There are a couple of ways to ensure that you are doing this properly to get the most bang for your buck:

With the static method, here are a couple of tips to remember: 

  • Protect the skin:  Most people know this but if you have static (non-moving) cryotherapy, then you should have a thin base layer that protects the ice from being applied directly to the skin which can cause frostbite where the ice is applied.

  • Increase the contact area: Using ice that is crushed up (so there aren’t too many hard corners pressing into a sore area), or better yet frozen gel packs, that can better conform to the shape of the body part that you are icing increases the contact area.

  • Drive it in: Putting a tensor bandage over top of the ice with some compression will help the ice penetrate deeper, especially to a joint which is harder to reach by cryotherapy.  Just think of it…the frost only penetrates so far down underground in the winter, doesn’t it?  

    • Consider using oscillating cryocompression, which is where you have frozen gel packs applied to the area, and there is a compression brace that goes over the ice and a machine applies compression in a squeeze and release fashion.  This will help flush out any metabolic byproducts from the inflammatory process.

    • Reactivate exclusively carries the PowerPlay cryocompression units for our clients to rent, or can be incorporated into our clients physiotherapy rehabilitation programs.
  • Respect the four stages of ice. I tell my patients this all the time:

    • It has to feel cold (you are putting ice on or near to your skin after all),

    • Then finally, it has to feel like the ice has melted (or ice pack thawed right out) and the area feels like it is back to normal.  However, when you touch the area that the ice was on, it is surprisingly cold!   

    • It has to feel numb which is from the nerves conducting electrical activity much more slowly due to the ice,

    • It has to hurt a bit which is from an intense constriction of the blood vessels in the area to slow down the flow of blood to the area


  • Apply it long enough:  If you respect the four stages, it will take between 17 and 20 minutes to go through the four stages if you are using the static method.  

With the second method of “ice massage”, you aren’t really massaging yourself per se. You aren’t taking ice and applying pressure to knead out those sore muscles. Rather, you are taking ice and applying it directly to the skin and continuously moving it over the sore and swollen area.  This works quite well for areas that are smaller and more focal, such as a sore smaller joint like your big toe or your thumb, a sore tendon insertion, one part of a larger joint like the inside of your knee.  Here is how it works:

  • You can either freeze water in a dixie cup and then tear off the top rim to expose some ice, or just take an ice cube and wrap a tissue around it.
  • Put a towel under the area you are going to be icing, because there will be drips.
  • Then move the ice over the area continuously for 7-9 minutes.  The same four stages will be experienced as mentioned above.
  • Here is a video of how to do it properly.

How often should you ice an injured or inflamed area?

It has been demonstrated that the effects of icing last in and around the 2 hour mark.  So, it would be safe to say that you can repeat the cycle of icing every two hours.  

Icing is really only effective in the acute or flared up stage, which usually is the first two weeks after an acute injury, or an acute flare if you have a chronic recurrent inflammatory disorder like osteoarthropathy (you can call it osteoarthritis if it is flared up).

The “ice”-ing on the cake.

I couldn’t resist.  In conclusion, cryotherapy (or icing an inflamed or injured area) in the right window of opportunity, for the right length of time, with enough compression (and maybe consider a cryocompression unit like the PowerPlay that we rent out and use in our physiotherapy studio) will have the best chance of providing you with the relief that you need.

That being said, once you are done managing the acute flare up of an inflamed area, then you need to look at the underlying cause of the inflammation, or treat the injury properly through a combination of soft tissue modalities (acupuncture, shockwave therapy, massage therapy) and then get on to rehabilitating the injury or chronic condition and stabilizing the affected area through a progressive customized exercise protocol that a physiotherapist can provide you.

Get back to enjoying the life you want to live.  Let us reactivate you so that you can live life to its fullest.