Ice vs. Heat Therapy

If you’ve ever had an injury, you would probably hear two distinct insights on injury management: ice and heat. Some people would encourage you to ice your injury, while the other half would tell you to warm it. Be honest—what do you actually do? Many people get it wrong. So, let us debunk some myths about the uses of ice and heat.

Firstly, it is crucial to understand the mechanism behind injury and its pain. When the body detects tissue injury by bacteria, mechanical trauma, heat or other causes, it activates an inflammatory response which involves inflammatory mediators, e.g. hormones histamine and bradykinin, to dilate blood vessels, resulting in higher blood flow to the injured region. This blood contains white blood cells to fight off pathogens that may infect the body. The reason why inflammation is painful is due to the hormones irritating nerves, hence pain signals are transmitted to the brain. This serves as protection as you tend to protect painful areas (InformedHealth.org, 2010). Along with more blood flow, blood vessels increase their permeability as well, allowing more blood components (e.g. fluid, white blood cells and proteins) to escape from the vessels and into the tissue, which causes swelling (Rogers, n.d.). When you have an injury, usually the site will be inflamed, painful, red, warm and swollen.

Ice is needed here for several purposes. Wheeler (n.d.) states that ice constricts blood vessels, which reduces inflammation and swelling. When inflammation is reduced, so is pain. Ice is hence suitable for pain management of injuries, especially in the first 24 to 48 hours post-injury. To apply ice, use a cold compress (or ice pack) or frozen vegetables if you do not have one. Place a thin towel or tissue on your skin so that the cold compress does not directly touch the skin to avoid any cold allergies and frostbite. The ideal duration for icing is 15-20 minutes. Wheeler further states that greater than 20 minutes of icing may result in reactive vasodilation, where the blood vessels dilate instead of constricting to ensure sufficient blood flow to a tissue. Research has shown that 30 to 40 minute-periods between icing sessions are ideal to prevent this from occurring. Essentially, you may ice for 15-20 minutes every hour.

Icing is suitable for injuries such as sprains (joint or ligament), muscle/tendon strains, bruises and any overuse injuries (e.g. tendinitis). The conventional RICE method (rest, ice, compression, elevation) is also effective to aid pain management for these injuries. Recently, alterations/additions to this method, e.g. PRICE (protection, rest, ice, compression, elevation) and POLICE (protection, optimal loading, ice, compression, elevation) are also beneficial.

On the contrary, there is an argument that icing does not help with injuries, specifically tissue recovery (Stone, 2015). Swelling was stated by Dr. Stone (2015) to be helpful as it is the initial healing response of the body right after an injury. However, it is actually not always advantageous. As stated in the same source, swelling “destructs and distends tissues, and distorts the anatomy.” Apparently, the enzymes in the fluid break down the tissue while stimulating it concurrently. Additionally, the first thing you would want to do post-injury is decrease its pain first, then repair the damaged tissues after that. Ice is most efficacious in decreasing pain, plus it also reduces swelling before it gets too large that the tissue is broken down instead.

Despite the strengths of ice therapy, heat also has its own benefits. Heat does the opposite of ice; it dilates blood vessels and thus increases blood flow. Since blood flow is heightened, tissue repair is promoted. Heat also increases flexibility and loosens up tight muscles, getting them ready for exercise. Injuries that is compatible with heat application include pulled/tight muscles, osteoarthritis, tendinosis (Here’s how to choose between using ice or heat pain, 2020), some cases of low back pain (Freiwald et al., 2021) and other pains, e.g. headaches and menstrual pains. The soreness you feel around 24 hours post-exercise, called delayed on-set muscle soreness (DOMS), is also better managed using heat. Applying heat to an injury is similar to applying ice — heat pad (or anything that is warm) is put on the injured area, with the skin layered with a tissue/towel to avoid any thermal burns, for 15-20 minutes (Wessler, 2021).

Nonetheless, there is a better alternative than solely using ice or heat: mix the two. In sports physiotherapy, therapists usually do a ice and heat contrast therapy, which combines both the functions of ice and heat so athletes benefit from both the treatments. Ice and heat are given alternately, repeatedly for a number of rounds. Besides this contrast therapy, it is advised to apply heat before an exercise to loosen up muscles and joints and increase flexibility (for physiological readiness to exercise) and apply ice after to the injured area to reduce any pain, swelling and inflammation.

In summary, ice and heat are applied for different reasons and different injuries—it all depends on what you are experiencing. Ice is generally better for new injuries and heat better for older injuries. Contrast therapy is an even better option for treatment, and it is advised to heat before exercising and ice after. Going back to the title’s question, there is really no simple black-or-white answer—everything depends on the situation.

References

Freiwald, J., Magni, A., Fanlo-Mazas, P., Paulino, E., Sequeira de Medeiros, L., Moretti, B., Schleip, R., & Solarino, G. (2021). A Role for Superficial Heat Therapy in the Management of Non-Specific, Mild-to-Moderate Low Back Pain in Current Clinical Practice: A Narrative Review. Life, 11(8), 780. https://doi.org/10.3390/life11080780

Here’s how to choose between using ice or heat pain. (2020, December 8). Cleveland Clinic. https://health.clevelandclinic.org/should-you-use-ice-or-heat-for-pain-infographic/

InformedHealth.org. (2010, November 23). Institute for Quality and Efficiency in Health Care. https://www.informedhealth.org/what-is-an-inflammation.html

Malanga, G. A., Yan, N., & Stark, J. (2015, January). Mechanisms and efficacy of heat and cold therapies for musculoskeletal injury. Postgraduate medicine, 127(1), 57–65. https://doi.org/10.1080/00325481.2015.992719

Rogers, K. (n.d.). How is inflammation involved in swelling? Encyclopedia Britannica. https://www.britannica.com/story/how-is-inflammation-involved-in-swelling

Stone, K. R. (2015, October 14). Why R.I.C.E. is not always nice, and some thought about swelling. The Stone Clinic. https://www.stoneclinic.com/blog/why-rice-not-always-nice-and-some-thoughts-about-swelling

Wang, Y., Lu, H., Li, S., Zhang, Y., Yan, F., Huang, Y., Chen, X., Yang, A., Han, L., & Ma, Y. (2022). Effect of cold and heat therapies on pain relief in patients with delayed onset muscle soreness: A network meta-analysis. Journal of rehabilitation medicine, 54, jrm00258. https://doi.org/10.2340/jrm.v53.331

Wessler, K. (2021, November 29). When to use ice or heat on an injury. OSF HealthCare. https://www.osfhealthcare.org/blog/when-to-use-ice-or-heat-on-an-injury/

Wheeler, K. (n.d.). Ice vs. heat: What should I use, when? OrthoCarolina. https://www.orthocarolina.com/media/ice-vs-heat-what-should-i-use-when