The Roles of Ice vs Heat in Post Injury Management
There is a lot of confusion surrounding the topic of whether to use ice or heat following a musculoskeletal injury. Many of our clients come to us having heard multiple differing opinions regarding this topic. Most healthcare practitioners (myself included) learned the R.I.C.E (Rest Ice Compression Elevation) principle in our schooling when it came to the management of acute tissue injury. The RICE principle was coined by Dr Gabe Mirkin back in 1978 (sidenote: Dr Mirkin himself admits today that he was wrong about the role of ice following acute injury) (1). The science behind this principle is that the local blood vessels will become constricted in response to the ice resulting in decreased local swelling and the pain will be numbed by the effect of the ice on the skin.
While ice does result in decreased local swelling and pain, recent research has shown that, by doing so ice is also delaying the healing process by inhibiting the body’s inflammatory response (2). It turns out, the body actually knows what it’s doing when it turns on the inflammatory process in response to tissue injury. The swelling process occurs as a way to quickly provide the damaged tissue with an influx of inflammatory cells which will begin the healing process. Inflammatory cells known as macrophages release a hormone called Insulin-like Growth Factor (IGF-1). IGF-1 is a hormone that aids healing in muscles and surrounding damaged tissues. When you apply ice to reduce swelling you are actually delaying healing by preventing release of IGF-1 (3). Anything, for that matter, that reduces inflammation will delay healing. For this reason, we also try to encourage people to avoid popping the ibuprofen in addition to avoiding cold therapy post injury.
What role can heat play in the post tissue injury environment? In response to heat, the local vessels will dilate resulting in increased delivery of blood to the injured area. This will insure that the delivery of inflammatory cells is not delayed unlike with ice. Research supports that heat can play a role in tissue healing and injury recovery in all stages of healing. A study published earlier this month in the Journal of Applied Physiology found that daily heat therapy (over a period of 10 days) on human muscle subject to immobilization prevented immobilization-induced loss of myofiber (single muscle cell) respiratory capacity as well as immobilization-induced loss of proteins associated with all 5 mitochondrial respiratory complexes (3). In other words, daily heat therapy applied for 10 days to immobilized muscle resulted in decreased atrophy (muscle loss) in human skeletal muscle. Other studies have also found that heat applied to muscles following intense exercise resulting in muscle break down resulted in preservation of muscle as well as decreased muscle soreness (4).
What role can heat play when managing chronic pain? We most often see clients once they are in the chronic stage of injury. Chronic pain occurs when an older injury (3 + months) never properly healed and as a result restrictions from that injury continue to cause pain and dysfunction to the individual. Many of the hands on treatment methods we utilize are based on the theory that we are re-inducing the inflammatory response to the injured area with the hope of setting up a better environment for healing and to allow for a more complete healing process to occur. For that reason, we always recommend heat following treatment. Whether the heat be applied through a warm bath, a sauna or a moist hot pad the goal is to stimulate increased blood flow to the treatment area.
I would also like to clarify that the application of heat or ice to an injury is a palliative method of treatment. Meaning that the application of ice or heat will only help to assist or inhibit a process that is stimulated by some kind of outside source wether that be through traumatic injury, intense exercise, or medically induced tissue trauma.
I hate to end this post without giving ice a little bit of credit when it comes to post injury management. Ice can play a role with conditions in which the inflammatory response is overactive such as with arthritis. Individuals dealing with arthritis pain and swelling would definitely benefit from utilizing cold therapy to reduce pain and swelling helping to flush waste products and reduce tissue breakdown. The use of cold therapy is also emerging as a beneficial treatment for unconscious individuals suffering from potential neurological damage. Therapeutic hypothermia is a type of cold therapy that has been shown to have neuroprotective effects which could potentially benefit people post acute Spinal Cord Injury (SCI) or Traumatic Brain Injury (TBI) and has most commonly been used in people who did not regain consciousness after cardiac arrest due to lack of blood flow to the brain tissue (5).
In conclusion, when it comes to using ice or heat for post injury management we most always recommend heat based on the latest research reviewed in this blog. There has been no significant research in the past 10 years that supports the use of ice for acute injury recovery or for decreasing the effects of strenuous exercise on muscle tissue. Despite the lack of research doctors, personal trainers, physical therapists, chiropractors and other medical professionals continue to recommend ice post injury and post recovery. The medical professionals have a duty to educate themselves on the latest research and to stay up to date on the latest recommendations when it comes to the most optimal treatment to provide to an individual suffering from tissue injury.
Knee Surg Sports Traumatol Arthrosc. 2015 Sep;23(9):2475-83. doi: 10.1007/s00167-014-2911-y. Epub 2014 Feb 23.
Journal of Applied Physiology. 2019 May 2; doi: https://doi.org/10.1152/japplphysiol.01098.2018
J Clin Med Res. 2013 Dec; 5(6): 416-425. doi: 10.4021/jocmr1521w
Int J Mol Sci. 2015 Aug; 16(8): 16848–16879. Published online 2015 Jul 24. doi: 10.3390/ijms160816848