I've received a few questions about icing, especially on the heels of some recent information which has come out debunking the benefits of using ice after a long or hard workout, and even after an acute injury.
The current argument goes something like this: when an injury occurs, your body creates inflammation as a healing response. So if inflammation is the body's natural way to heal an injury, why would you want to block this inflammatory process with ice? Let me share some thoughts on this, for your clarification.
Ice does not completely reduce swelling from inflammation, but it can prevent excessive swelling from happening for a long period after the initial injury occurs. Some swelling does assist important healing aspects such as white blood cells and other chemicals involved in the healing process to migrate into damaged tissues through increased vascular permeability. Swelling also physically protects an injured area through decreasing it's potential range of motion. There is, however, no physiological reason to allow swelling to freely progress for hours or days after an injury occurs, especially if you have access to ice or cold water.
Prevention of excessive swelling is important because fluid that has escaped into the tissues from excessive swelling can, among other things, create a low oxygen environment that can lead to additional tissue damage and delayed healing. In addition, swelling can cause distention in joint capsules and other tissues, and excitation of nervous system components (those darn mechanoreceptors), which can lead to more pain. Ice reduces this by shrinking blood vessels surrounding an injury.
- The cold temperature of ice can slow down nerve conduction speed and shut down the activation of your proprioceptors (muscle spindles), making it an effective pain reliever and muscle relaxant. If a muscle is in less pain and is more relaxed, mobilization and movement become easier, and a return to movement and, ultimately, training can occur much more quickly, which can limit any loss of fitness and keep you happier!
- Ice also reduces metabolic activity in the tissues that you ice, making them better able to resist the damaging effects of the impending loss of oxygen from inflammatory swelling pressure. In other words, lower tissue temperatures from icing means less oxygen is required by your muscles to sustain their integrity.
- And lastly, at least for now, ice causes vasoconstriction, or shrinking of blood vessels. Unless you are in extreme circumstances where you must shuttle blood to your brain to survive, your body will avoid tissue death by not allowing the body part you are icing to cool excessively. Through a process called "reactive vasodilation" (aka Hunting reflex or Lewis reflex), your vessels, while being exposed to cold, create a negative pressure in the capillaries. This negative pressure causes a pumping of inflammatory byproducts out of an injured spot, while allowing additional healing components such as white blood cells to cascade into the area. When combined with pressure and elevation, this pumping action of ice can be an effective rehab tool. Ever wonder why, when you jump into cold water and "ice", your skin turns red? This is why! Reactive vasodilation.
All in all, icing and cold have very therapeutic effects and can be a very important part of optimizing recovery and healing. Limit your exposure to five to 10 minutes, in most instances.
Next up, and explanation of what I am about to do here at home-- jump into a COLD SHOWER. Why on earth would I do this, you might ask? Well, all the typical jokes aside :), enough of my athletes have asked, so a post about the benefits of that coming up!