by Paul Clement
If you’ve ever sprained or strained an ankle or knee, or suffered from a muscle or joint bleed, you’ve probably heard that a couple of days of rest, ice, compression and elevation—RICE—is the surest route to recovery. But this simple at-home treatment has increasingly been called into question, especially the “rest” and “ice” parts. Many physicians and researchers now believe that rest and ice may actually delay or prevent proper healing.
RICE guidelines have been recommended by coaches and healthcare providers for over four decades—ever since the term was coined by Dr. Gabe Mirkin in his 1978 publication Sports Medicine Book. The intent of RICE was to speed the recovery process by reducing inflammation, swelling and pain. However, subsequent research demonstrated that icing actually prolongs the healing process. Dr. Mirkin recanted his original position in 2015, and today, he advises against icing an injury.
How can icing delay or prevent proper healing? When you’re injured, the body responds with three phases of recovery: 1) inflammation, 2) repair, and 3) remodeling. Each phase must successfully occur in order for the next phase to proceed and be successfully completed. That means inflammation must occur before the repair process can begin. If you reduce inflammation, then you delay the healing process.
Why is inflammation good? Immediately after an injury, blood vessels in the damaged tissue constrict (called vasoconstriction) to reduce blood flow; simultaneously, the blood clotting process (called hemostasis) occurs to reduce blood loss. Immediately after vasoconstriction, a type of immune cell in the damaged tissue, called mast cells, release inflammatory chemicals, such as histamines, which cause the blood vessels to expand (vasodilation) and become more permeable. This initiates the inflammatory process and allows other immune cells, called neutrophils, which are attracted to the site of the injury, to leave the blood vessels and enter the space between the cells, where they destroy damaged cells and mediate the inflammatory process. This sets the stage for another type of immune cell—macrophages—to come in and remove dead cells and release growth factors which are necessary for healing. When this process is complete, the neutrophils self-destruct, ending the inflammatory phase of the healing process.
The inflammatory process is extremely complex and researchers are still learning about it at the molecular level. We know that the inflammatory process is not always good: in some auto-immune diseases such as rheumatoid arthritis, neutrophils that enter a joint during inflammation do not self-destruct, ending inflammation, but hang around and attack the cartilage lining the joints, destroying the joints.
Icing an injury delays healing by slowing inflammation. It slows the activity of clotting factors, slowing the formation of a clot. It prevents vasodilation, which slows the movement of immune cells into the damaged tissue, and the movement of waste out of the damaged tissue. It prevents the release of growth factors necessary for healing. And it increases the permeability of the lymphatic system, allowing fluids to flow in the wrong direction: from the lymph vessels into the injured area, increasing the amount of local swelling.
Icing can help reduce pain, but many physicians now recommend using acetaminophen (Tylenol) to reduce pain, and not ice. Finally, do not use anti-inflammatory drugs, such as ibuprofen (Motrin), to reduce pain: these drugs also reduce inflammation and slow healing—in addition to interfering with the clotting process, which may prolong bleeding.
Next week: Why movement helps in the healing process.