SaveYourself.ca • Sensible advice for aches, pains & injuries
updated 1/27/12
Not sure when to use ice or heat? Get a quick overview in The Great Ice vs. Heat Confusion Debacle, or a detailed look at why you should (almost) never ice low back pain. And here’s an intriguing update: Voltaren® Gel, an anti-inflammatory medication that you rub on, was FDA-approved in the US in 2007, and is the only other way to do what icing does. Learn more about Voltaren® Gel.
Icing — “cryotherapy” for therapy geeks — is an essential injury management skill. Everyone should understand icing the same way everyone knows how to put on a Band-Aid. It is a cheap, effective, drugless method for relieving the pain of injuries. Safe application of ice to your skin can relieve symptoms from sprains, strains, bruises, and tendinitis — virtually any situation in which superficial tissues are inflamed by trauma. Icing could also assist recovery from repetitive strain injuries like tendinitis or iliotibial band syndrome, although that is less clear.
But there also hazards and complications that anyone with chronic pain absolutely needs to know. This article is full of tips and insights about icing that will take you way beyond the basics!
My strained thigh muscle felt like a broken bone at first, but I'm using your icing method and it’s responding brilliantly.
— Paul Farley, West Sussex, England
Ice is for injuries. It is only useful where tissue is damaged and/or “inflamed.” (As you’ll learn below, some things that we think of as “inflamed” aren’t actually inflamed.)
Icing is primarily an analgesic — a pain-reliever — and not an actual treatment. That is, it doesn’t “fix” anything. Use it like you use ibuprofen. It may help to resolve chronic problems (much more about this below), but it’s mostly intended to numb painfully inflamed or other hurting tissues.
The most commonly iced acute injuries are fresh injuries — ligament sprains, muscle strains, and severe bruises. (When the skin is broken, things get little trickier.) And what’s a “fresh” injury? Any time tissue has been physically damaged, it will be inflamed for a few days, give or take, depending on the seriousness of the injury. If superficial tissue is sensitive to touch, if the skin is hot and red, if there is swelling, these are all signs that your injury is still fresh, and should definitely not be heated. Heat will increase the circulation and significantly facilitate the immune system activity.
Ice is also often helpful with chronic overuse or tissue fatigue injuries like carpal tunnel syndrome, tennis elbow, supraspinatus tendinitis, iliotibial band syndrome, patellofemoral pain syndrome, shin splints, and plantar fasciitis. There are others, of course, but these are the most common.
Ice may also be useful for garden-variety “wear and tear” arthritis, and sometimes the nasty inflammatory arthritides (rheumatoid, ankylosing spondylitis).
Ice can mildly aggravate the pain of muscle spasm and trigger points (muscle knots). Trigger point pain is extremely common, and is routinely mistaken for an “iceable” injury, especially in the low back. Here’s the short explanation:
Back pain is rarely an injury — that is, the pain is rarely caused by inflammation which might be helped by ice. Even in cases where inflammation is present, it is usually deep in the back under a thick layer of insulating muscle and the ice cannot “reach” it. However, back pain almost always involves muscular trigger points (muscle knots), which are more likely to be aggravated by ice and helped by heat! For this reason, the majority of people with back pain prefer heat, and a few have negative reactions to ice. For similar reasons, neck pain usually should also not be iced. Although experiments have shown that both ice and heat are modestly helpful for low back and neck pain, there are good reasons to err on the side of heat. Ice should only be used on the back by patients who clearly prefer it (for whatever reason), or when there is definitely a fresh injury.
The stakes are not high. Studies have shown that people usually get mild benefit from ice — about the same as heat in fact.1 But there are good reasons to err on the side of heat nevertheless. If you have low back or neck pain, this topic is covered in much more detail in (Almost) Never Use Ice on Low Back Pain!.
But the low back is only the most obvious example, because it is both much tougher and immune to injury than people think, and also much more prone to painful trigger point activity than most people realize. In fact, the vast majority of garden variety aches and pains are dominated not by arthritis and injury as people tend to assume, but “just” by muscle pain — which tends to be irritated by ice, and generally would rather have a hot pack and a massage.
When tissue is damaged, the body responds with a complex array of chemical and neurological changes collectively known as inflammation. For instance, the capillaries widen in a big way to bring extra oxygen and nutrients to the area. They also “loosen,” becoming more permeable, to give immune system cells easy access to the injury.2 Most of the pain and discomfort of inflammation is due to the immune system reaction.
If the skin is broken, there is a risk of infection, and the immune system reaction is essential — a pure physiological goodness. Inflammation in that context is a machine finely-tuned by evolution to optimize recovery, just as a fever is an effective physiological process for fighting infection (indeed, they are closely related processes). Strictly speaking, if you to want to heal well, don’t interfere with inflammation! For broken-skin wounds, use ice only a little to “take the edge off.” And course it’s best to use it in a sterile way, so that you don’t add to the infection risk!
If the skin isn’t broken, things are really quite different! In this context, inflammation is an absurd overreaction that causes collateral damage and excessive pain for no good reason at all — a glitch in biology In this context, inflammation is an absurd overreaction that causes collateral damage and excessive pain for no good reason at all — a glitch in biology., with a recently discovered and clear evolutionary explanation.3 There is simple no need for the immune cells to get all fired up for a sterile, internal injury where there is no possibility of infection. Nevertheless, they do get fired up. But the important point here is that the inflammation here is truly worse than it needs to be — and it’s quite reasonable to try to suppress it with ice (and anti-inflammatory medications like ibuprofen). Bet you didn’t know that. Very few people do — this is based on surprisingly new science!
The immune system reaction is not the only reason injuries hurt. Damage cells put out many kinds of distress signals. As with most biological processes, our comfort is not really a priority. In fact, quite the opposite — inflammation has partly evolved to be painful. Cavemen didn’t have ibuprofen and ice, nor did they have the benefit of understanding inflammatory chemistry. In the big picture, it was good of our species that inflammation was super painful: the victim was encouraged to stay relatively still while inflammation was left to run its course like a fever!
But for modern humans, inflammation is … well, it’s overkill. We can afford to “turn it down.” We can ignore the warning of the inflammation, to a point. Ice can only turn it down so much anyway, so there’s not risk of missing the pain alarm entirely!
Cold slows metabolic activity, numbs nerve endings, constricts capillaries. It limits and controls inflammation. It makes it hurt less. It helps us get through the day. And that’s an especially good thing for sterile injuries, where the inflammation is largely pointless.
There’s yet another kind of “inflammation”…
Do you have chronic pain? Chronic inflammation? Shin splints for two years? Plantar fasciitis for five? Then you are probably thinking, “Inflammation is not @#!!$% a valuable warning signal!” It’s more like an annoying car alarm.
Right you are. Sort of.
What’s going on in a repetitive strain injury like runner’s knee or tennis elbow or Achilles tendinitis is not really inflammation, per se, except perhaps in the earliest stages,4 but erratically painful degeneration56 — tissue rot, which has more in common with arthritis than inflammation. The chemistry of these situations is very different than classic inflammation, and in particular involves relatively little immune system activity. The most obvious implication of this is that medicines intended to suppress immune system activity — the anti-inflammatories — are obviously not going to work well. And they don’t.
So what of ice, then? The most basic of all anti-inflammatory treatments? Ice can relieve many kinds of pain temporarily by numbing nerve endings, of course. But does it do anything else?
If ice can help a repetitive strain injury in any way beyond brief numbing, no one has ever actually proven it, or shown how it might work. There’s little doubt that it’s relieving in the short term, and there is some reasonable speculation that it could stimulate miscellaneous minor tissue healing processes. Virtually any stimulatory input to the body, up to a point, can provoke a healthy response, because of the use-it-or-lose-it principle. Stress a tissue, and it will probably get tougher in some way. In broad strokes, that is probably the only plausible therapeutic mechanism of icing. Ice may simply be one of the easiest delivery systems for a bit of non-toxic stimulation — a way to stimulating tissue without overloading it, while simultaneously give some temporary pain relief from numbing.
The great advantages of ice as a treatment are not its impressive biological effects, but its thrift, ease, and safety: treatment options simply don’t get any more innocuous while still having some plausible mechanism of benefit.The great advantages of ice as a treatment are not its impressive biological effects, but its thrift, ease, and safety: treatment options simply don’t get any more innocuous while still having some plausible mechanism of benefit. Therefore ice remains firmly on my “worth a shot” list for RSIs. Keep your expectations low, but there are virtually no risks, other than ice burn (which takes at least a couple minutes of raw ice application, probably twice that). However, it certainly isn’t “anti-inflammatory”!
An excellent method of therapeutic icing is to use bare or “raw” ice — that is, ice applied directly to the skin, with no layer of plastic or fabric between you and your ice.
Raw ice delivers more of an icy punch! This is due to the spreading of melt water into every crevice, which conducts heat more efficiently away from the skin both directly into the ice, and via evaporation.
In comparison, gel packs and bean bags are comparitively wimpy cryotherapies (although they have their place, as you’ll see). They tend to warm up too quickly (especially where the skin is hottest and needs the most icing), and they sometimes cannot shape themselves well (or gently) to the contours of the injured body part. There are times when they are handy or easier when the stakes are low, but for serious icing of acute injuries or a stubborn tendinitis, you really need an ice cup.
A styrofoam cup is an elegant delivery system for raw ice …
The humble styrofoam cup is the cheapest and most effective injury management tool in my office and in my own home. It’s not the cup itself that’s so useful, of course, but its contents — ice! Don’t wait until you’re hurt to do this — have them ready and waiting.
In a pinch, with no cups around, just use an ice cube held in a dishtowel — less convenient, especially for larger areas, but nearly as effective. Over the years I’ve found that, despite the best intentions, 9 times out of 10 that I need an ice cup, I haven’t actually got one ready in the freezer, and I end up using ice cubes at first!
One of the downsides of the styrofoam cup option is that it’s a bit wasteful. Wouldn’t it be better to have a re-usable plastic cup designed for the same purpose? There are several brands of ice cups, like the CRYOCUP™ and the Pro-Tec Ice-Up Portable Ice Massager. I’ve never used one personally, but they seem like a great idea, especially for anyone who lives on the edge and brings home new sports and adventure injuries on a regular basis.
In fact, there are even insulated icing tools designed to be taken to the field or the mountains or wherever you think you might need ice.
And although it’s not at nice as ice, an alternative worth mentioning is a simple chemical ice pack — the kind you crush to activate. Despite their inferiority (they aren’t as cold as ice and won’t last as long), I have succumbed to their convenience, and these are what I’ve actually been taking on expeditions for a while now.
Slide the ice over the inflamed area in a slow but steady pattern. It’s important to keep moving, as long as you don’t try to ice such a large area that tissue gets a chance to warm up before you return to the starting point.
Continue ice massaging for 1–3 minutes, or until it is numb, whichever comes first — no more. “When you’re numb, you’re done,” is the rule of thumb for safety (see next section). Areas with thick tissue, like the top of the thigh, will take longer to get numb. Thin areas, like the side of the knee, will usually go numb quickly.
What does numb feel like? Just close your eyes and lightly touch the skin. If you can’t feel it at all, or if you can feel only pressure, that’s numb enough. Stop icing and let the tissue warm up.
You may have heard that bare ice is too cold to use directly on the skin in this way. That’s untrue for short periods. Although a cold-sensitive person may find raw ice too uncomfortable, tissue damage can only occur after sustained icing — well after you have gone completely numb, at least 3 minutes. Stopping roughly when you get numb pretty much guarantees that you won’t hurt yourself.
An ice treatment will feel like it is burning or stinging at first, and that’s okay. Icing this way can feel a bit nasty, especially at first in certain locations, but stick with it: the powerful anti-inflammatory effect is worthwhile. In many situations, this is a much better solution than an anti-inflammatory medication.
When you’re numb, you’re done.Once your tissues warm up again, you can repeat the treatment. In fact, you can apply the ice as often as you like, as long as your tissues have a chance to mostly warm up between treatments. In the case of tenditis, you can continue doing a lot of icing — many applications per day — as long as you still have symptoms, and even when you are feeling better.
In the case of injuries, icing is mostly just useful while the injury is still hot, red, swollen or painful — this phase may last for a few hours or several days. When these signs begin to fade, you may be certain that you would have been stuck with them for a lot longer if you had not been icing.
People often tell me that they have “tried icing” for an overuse injury like iliotibial band syndrome. A little quizzing usually reveals that this means that they have occasionally applied ice once or twice in a day, only when the need felt greatest. That is not really enough to know whether or not icing is going to help you.
Power icing is the name I’ve given to icing in megadoses — 20–50 applications of ice per day for 3–20 days at a time. As long each dose is no more than three minutes, and if you allow sufficient opportunity for tissue to warm up between applications, this is not risky — the worst case scenario is that you’ll waste your time.
I prescribe power icing only for serious chronic overuse injuries, especially the common tenditises (mostly tennis elbow), plantar fasciitis, some cases of carpal tunnel syndrome, iliotibial band syndrome, patellofemoral pain syndrome, and some kinds of shin splints.
Unfortunately, I have no scientific evidence that this works! It seems to make a certain amount of sense — more of a good thing? — and I have had some success with it with my own clients, a few slightly amazing recoveries with just a few days of power icing. Generally speaking, there is no excuse for prescribing self-treatments that lack even a clear rationale, let alone research evidence that they work. However, this one can be justified simply because it is low cost and low risk — so it is worth a shot!
I also prescribe power icing simply to make sure that people giving “normal” (lower dosage) icing a fair shot. Sometimes I will sneakily prescribe 50 applications of ice per day, knowing full well that the “type A” client isn’t actually going to fit in more than about one third that much — and that’s actually good enough for me.
The inevitable question with power icing is “how much?,” a conversation I find myself having with clients even after the numbers have been laid out. One way of clarifying is simply to say that it should be so much icing that you start to get sick of it. If you’re not thinking, “Wow, geez, this is really a lot of icing!” then you should probably do more.
If it doesn’t seem to be working within 3-5 days, it’s probably not going to do the trick for you. But I strongly recommend that you give it at least three days, so that you can be certain that you really have “tried icing!”
You can definitely enhance the effect of icing by using an ice gel afterwards. This is different than the gel-packs — it’s a goopy blue paste in a jar that feels very cold when you rub it into your skin. A variety of brands are available at any larger drugstore. There is one downside to this technique: if your goal is to do many sessions of icing, your skin tissue takes much longer to warm up between sessions when you’ve applied an ice gel.
Gels packs and other non-raw icing are preferable when you are trying to “reach” deeper tissues.
Obviously, cryotherapy takes longer to effect deeper tissues than it does to effect shallow ones. Moments after you apply raw ice, your dermis and epidermis are definitely colder — but tissues under that may be unchanged. How deep can ice reach? How long does it take? Unfortunately, it’s just not clear. It may not reach very far, and it may not happen very quickly, and it undoubtedly depends on a number of different variables.
One thing is for sure, though: if you want to chill deeper, thicker tissues, you need gentler, slower cooling. Ice packs to the rescue! Raw ice is probably too cold to leave on for long enough to chill any tissue deeper than about a centimetre. Roughly. So you need to use a gel pack instead.
You can also use fabric or towels to further ease the intensity of a gel pack, so that it can be used safely for even longer periods.
If you’ve read this far, you now know much more about icing than most people, and indeed most health care professionals. Congratulations!
Comments: What’s better for neck and back pain — ice or heat? This experiment, conducted at a university-based emergency department, compared the effectiveness of these two common treatments. Everyone studied received 400mg of ibuprofen orally and then thirty patients were given a half hour of either a heating pad or a cold pack.
SaveYourself.ca. 4902 words. BACK TO TEXT BACK TO TEXT Comments: A well-written and important bird’s eye view of the subject of tendinopathy, presenting an updated way of thinking about the problem. Highly recommended, required reading for professionals. BACK TO TEXT Comments: From the abstract: “If physicians acknowledge that overuse tendinopathies are due to tendinosis, as distinct from tendinitis, they must modify patient management …” BACK TO TEXT