Should I ice my injury or apply heat?

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This is a question we get asked quite regularly by people with an acute or recent injury. A quick Google search of “should I ice or heat” can come up with some confusing results; do one for first 24-72hours before doing the other, don’t put ice on for longer than 10 to 30 minutes, ice is better against swelling, heat is better for stiffness and muscle pain, and now there’s information suggesting ice is delaying healing?

It’s no wonder this question is being regularly asked! The variety of results seems rather confusing!

The aim of this blog is to provide some updated information about the effects of ice or heat, or if either of them provide any benefit at all.

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Rest. Ice. Compression. Elevation.

R.I.C.E. is a fairly common acronym most people who have taken a first aid course would be aware of. We can thank Dr Gabe Mirkin for coming up with this term in a book he wrote in 1978. The intended purpose of applying ice to an injury site was to decrease the blood flow and minimise the swelling occurring and therefore reducing the overall unwanted inflammation within a joint or muscle. This can be done through a number of modalities such as using ice packs, frozen bags of peas, or even the controversial ice aerosol or ‘magic’ spray that you might occasionally see whipped out at your local footy game.

However, inflammation is not the evil thing we believe it to be - our bodies need inflammation to occur in order for our tissues to heal. Without inflammation our body wouldn’t be able to transport the cells responsible for tissue repair to an injury site, and also remove unwanted debris such as damaged tissue and bacteria in the case of a wound.

Dr Mirkin himself has even spoken out about his original works and stated that ice may ‘delay healing, instead of helping’ (Mirkin, 2017). This theory is based on the fact that if we restrict inflammation and thus the body’s natural healing process, this could potentially delay recovery - however there has not been any robust evidence yet conducted that proves that ice does more harm than good at present.

It is also worth mentioning that ice provides a rather poor anti-inflammatory effect, and although it may slow down the rate of blood flow to the skin and peripheral tissues by a small amount, the ability to cause an effect on inflammation is negligible (Sarver, 2017 & Siqueira, 2018)

It would be similar to attempting to put out a roaring campfire with a handful of ice cubes.

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“I feel better after icing, isn’t that helpful?”

Ice can certainly assist in providing pain relief (Garra,2010), but probably not for the reason you think - remember that its effect on slowing down inflammation is relatively poor. Applying something external, onto an area of your body that is feeling sore or painful simply provides a different input or stimulus that your body and your nervous system has to then process and make sense of.

These external inputs aren’t just temperature related such as the case of ice / heat, a different external stimulus could even be touch and pressure related like scratching an itch or getting a massage.

In the case of something icy-cold, multiple sensor and pain receptors on your body become affected by the change in temperature and the cold sensation provides a numbing-like sensory input which can affect the pain or discomfort you feel – although only temporarily!

If you want to know more about the meaning of pain I’d suggest checking out our blog on ‘what is pain’.

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Heat packs, rubs and patches.

“I think I ‘pulled’ a muscle a few days ago, there’s no pain but now it feels tight and stiff – should I put heat on it?”

You can if you’d like to, but it’s not really that important or necessary! Similarly to how ice provided a numbing effect to alter the sensation of pain, heat can provide a warming or relaxing affect that again simply provides your body with a different sensation that helps you feel more relaxed, less stressed, and less “tight” – think about how some people enjoy warm baths or taking a hot shower during the middle of winter.

If you are putting heat packs on your body in order to affect underlying deep muscle tissue, and structurally alter the length of them, sorry to say, but you’re probably not going to be able to achieve that result (Myrer, 1997). Even less can be said for warming creams, gels and adhesive patches – unless you enjoy the smell of them! Remember that it’s actually quite difficult to alter these systemic processes your body has, and by rubbing a cream onto your body, it’s unlikely you are penetrating through the layers of skin, fatty tissue, connective tissue and muscles and heating up and ‘loosening a tight muscle’ (Draper, 1998).

This would be like lighting a candle in your freezer in order to soften up your ice-cream, sounds rather ineffective right?

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Summary

So as the literature would suggest, although these various modalities are not going to have a significant impact on inflammation or muscular tension / stiffness, they are probably not inherently bad for you either.

Are they necessary to do? Well much like our blog on ‘To stretch or not to stretch’ - it seems that the impact of these are largely dependent upon the individual, and their preferences. If you enjoy the feeling that either of these things provide, then go for it! If you can’t be bothered with making trays of ice or putting the wheat bag into the microwave, great news, you’re not missing out on much either.

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References

Draper DO, Harris ST, Schulthies S, Durrant E, Knight KL, Ricard M. Hot-Pack and 1-MHz Ultrasound Treatments Have an Additive Effect onMuscle Temperature Increase. J Athl Train. 1998;33(1):21-24.

Mirkin, G., Why ice delays healing. September 16, 2015.Accessed June 1, 2021. https://www.drmirkin.com/fitness/why-ice-delays-recovery.html

Garra G, Singer AJ, Leno R, et al. Heat or cold packs for neck and back strain: a randomised controlled trial of efficacy. AcadEmerg Med. 2010;17(5):484-489. doi:10.1111/j.1553-2712.2010.00735.x

Myrer JW, Measom G, Durrant E, Fellingham GW. Cold- and hot-pack contrast therapy: subcutaneous and intramuscular temperature change. J Athl Train. 1997;32(3):238-241.

Sarver, D.C., Sugg, K.B., Disser, N.P. et al. Local cryotherapy minimally impacts the metabolome and transcriptome of human skeletal muscle. Sci Rep 7, 2423 (2017). https://doi.org/10.1038/s41598-017-02754-5

Siqueira AF, Vieira A, Bottaro M, et al. Multiple Cold-WaterImmersions Attenuate Muscle Damage but not Alter Systemic Inflammation andMuscle Function Recovery: A Parallel Randomized Controlled Trial. SciRep. 2018;8(1):10961. Published 2018 Jul 19. doi:10.1038/s41598-018-28942-5

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