Heat or Ice? Understanding Injury Management

Should I Apply Heat Or Ice On My Injury?

I get this question at least once a week. Its a relatively simple answer if you follow the rule ice for the first 48 - 72 hrs following injury and heat after that, but to fully understand when to use heat or ice and to get better results from your treatment it requires a bit of explanation. Because there's quite a bit to talk about I’m going to do this over a few of blog posts. Read part 2 of this post here.

How Heat and Ice Affect Our Body?

Heat and Ice both have physiological effects on the tissues that they come in contact with. Applying heat cause blood vessels to dilate (vasodilation) which increases the local blood flow and applying ice does the opposite (vasoconstriction), which will slow the blood flow down to that area. In addition to this they both have analgesic effects. Heat tends to have a soothing feeling while ice numbs the pain.

Stages Of An Injury?

To work out whether to use heat or ice we first need to understand what is happening to our body during an injury. The initial stages following an injury are usually when rapid vasodilation takes place and inflammation sets in. There might also be damage to blood vessels resulting in bruising. The things that you will notice are that there is evident pain and swelling, as well as redness, heat and loss of function - the 'cardinal signs of inflammation'.

Think of last time you had (or witnessed) a badly sprained ankle and you'll get the picture. If you don't get the picture, then here's a picture for you!

Ankle swell and internal bleeding

This is the situation when ice is appropriate. The ice will counteract the vasodilation and slow the inflammatory process, which means that you will have less swelling and less pain. Now if you were to apply heat then you would actually create more inflammation. The good news here is that your body usually tells you if you're doing the wrong thing in the way of giving you

The inflammatory phase of an injury usually last 48 - 72 hrs. Once the inflammation has stopped then we want to use heat to cause vasodilation to improve the blood flow to the Injured area. Why do we now suddenly want to encourage the blood flow when we were only just trying to stop it? Our blood is comprised of many things, some of which promote healing - oxygen, nutrients, white blood cells. The better the blood flow, the faster the healing. Look at your mouth & tongue for instance. It's red because it's got such a great blood supply, which also makes it one of the fastest healing parts of your body. Fact!

How To Apply Heat or Ice

Now as for the next question, how long to leave the heat or ice on for?  It is generally accepted to apply heat/ice for around 15 to 20 mins once an hr, then reapplying. This will give enough time for the areas underneath the skin to respond to the temperature change, but not so long that you will injure your skin. Keep this up for as long as possible to maximise the benefit (within reason). There are also some useful products on the market, which will allow you to apply the heat/ice for long periods of time without having to hold it in place. I'll talk more about products and the best ways to apply heat/ice another time.

Make sure when you're icing that the ice pack is wrapped in a tea towel so that you don't give yourself an ice burn. When using heat don't apply anything too hot. You should be able to feel the heat penetrating your skin but it shouldn't be uncomfortable or burning. Listen to your body - if something feels too hot then it probably is!

So now you know the basics of when and why you apply heat or ice.  Stay tuned for my next blog post which will focus on exceptions to the 48-72 hr rule and some more advanced ways using heat and ice to treat your injuries. Want to know more about Ice Vs Heat? Read part 2 of this post here.

Rhys Donovan Biomechanics Healthcare Cronulla. Osteopathy, Massage, Acupuncture, Exercise Physiology.


By Rhys Donovan

Owner and Osteopath of Biomechanics Healthcare

Disclaimer: This information is intended as a guide only and not to be taken as proper advice for anyone's specific condition. Always seek professional advice first before attempting to treat your injuries/condition.

Got a question? Send us an email and we'll get back to you A.S.A.P. For urgent inquiries please call our clinic 9527 3322.


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