The use of the RICE protocol is almost entirely based on subjective evidence and an understanding of the biology of muscle and ligament injury. Injury to a muscle or ligament is not limited to the initial mechanical damage. That is, a muscle pull involves more than just tearing to the tissue. Acute damage to a muscle or ligament initiates a cascade of events that can last for several minutes, even hours. Once injured, various enzymes and other co-factors are activated and released by the damaged cells. The enzymes quickly begin to degrade proteins and membranes in the injured area causing tissue necrosis. The result is what many refer to as “secondary injury” which causes further damage to the injured area. The co-factors released into the injury area initiate an inflammatory response. Both injury and inflammation cause increased blood flow and movement of fluid into the injured area. The result is pain and swelling. If not arrested, secondary damage, inflammation and swelling can aggravate the injury and delay to recovery process. Thus treatments for acute injury are directed towards preventing secondary injury and inflammation as well as reducing pain and swelling
Well designed clinical studies on the effectiveness of RICE are very limited. This is a difficult area to study given that RICE is the prevailing method of treatment. Many researchers are unwilling to compare RICE treatment to a control condition (no treatment). However, there is solid biological evidence of how each component affects the injury and recovery process. First, Rest, or immobilization, limits further damage to the area by preventing unwanted movements. Movement of an injured joint or muscle can cause additional tearing of the injured tissue and increase the pain sensation. Second, Ice is known to accomplish two goals. Cold application decreases cellular respiration. This, in turn, limits the activation of degredative enzymes and release of pro-inflammatory factors. Both effects reduce the extent of secondary injury. Ice also causes constriction of blood vessels which reduces blood flow and prevents swelling. Third, Compression seems to speed the rate of cooling of the injured area. It also mechanically reduces the blood flow into the injured area. Compression can also act to brace and limit unwanted movements. Finally Elevation decreases hydrostatic pressure to the injured limb reducing the accumulation of fluid and preventing further swelling
From a clinical standpoint, a handful of well-designed research studies do allow trainers to arrive at some overall conclusions regarding ice treatment and injuries:
These studies also allow trainers to make a few recommendations the application of RICE to muscle and joint injuries:
Elevate the injured area.
Despite limited clinical evidence concerning ice and injury, one can confidently conclude that rest, ice, compression and elevation (RICE) to injured areas can reduce pain and swelling and speed recovery to participation. As with all injuries, it is most important, however, to seek a medical evaluation as soon as possible.