The battle between ice and heat as treatment methods for pain and injury has long been controversial. There are benefits to both recovery methods, and you might just leave it up to a personal preference of whether you enjoy sensations that are warm and cozy or chilling and numbing.
To be clear, using either is going to be better than doing nothing at all, especially within that immediate post-stress window, where you should be working to reduce the onset of inflammation, pain, bruising, and other symptoms. Applying one method (or even alternating between the two) ASAP can prevent the injury from exacerbating, and can speed up your recovery.
Heat is an effective treatment for pain, causing increases in blood flow, metabolism, and elasticity of connective tissues. It can also help reduce joint stiffness. There is limited evidence to support this in reference to injury, but we have seen that heat helps with short-term reductions in pain and disability in people experiencing acute lower-back pain (plus subjectively better pain relief from delayed onset muscle soreness [DOMS] than its cold counterpart).
Should You Use Heat or Ice for Injuries?
If you choose to use ice and cold therapy to treat pain and reduce stiffness, application for 20 minutes is a nice sweet spot.
“There are no real guidelines other than 30 minutes maximum when using ice, based on research,” physical therapist and personal trainer, Leada Malek, PT, DPT, CSCS, SCS, says.
Stopping a bit short of that time limit, however — especially when using cold therapy — protects the skin and lowers the risk of irritation.
Overall, when it comes to pain and impact on healing, heat and ice are pretty close, according to the evidence. However, the order in which you use them does make a difference here. Here's how to treat your injuries efficiently and avoid damaging the affected area any further.
Always Use Cold Therapy First
Cold therapy wins when it comes to treating an injury immediately upon onset, as it most efficiently targets and reduces swelling and is the preferred method for easing pain by numbing the area.
“Heat therapy is a great form of treatment for muscular injuries; however, it is important to note that it shouldn’t be used immediately after an acute injury, such as a strained hamstring, broken bone, dislocated shoulder, or any other sudden injury associated with trauma,” Ryan Daly, a sports performance coach for professional athletes says.
Acute injuries cause bleeding in your tissue (a.k.a. swelling) and heat therapy will only make this worse, as it’ll heat up the blood and make it flow faster.
“You don’t want too much swelling immediately after an injury, as it will slow the healing process," Daly says. "Instead, follow the ‘RICE: rest, ice, compression, and elevation’ protocol to best reduce swelling."
It’s imperative to reduce swelling when you first get injured to accelerate recovery time and mitigate and prevent any further pain. One of the best forms of cold water therapy is running a cold or ice bath. Daly recommends using Plunge for immediate access to cold therapy and a prepared ice bath at home.
Set Cold Therapy Goals
Set a goal of doing cold therapy for at least the first week following an injury to best reduce swelling.
“If you are using just ice as cold therapy, it is recommended that you repeat the process, with 20 minutes on and 20 minutes off, for the first few days,” Daly explains. “If you're doing cold water therapy, such as a dip in a Cold Plunge, I recommend doing up to 10 minutes — if you can make it that long — with the first three days focusing on only cold therapy, rest, compression, and elevation, to reduce the swelling most efficiently."
But beware, however, that longer is not always better. While ice may help reduce swelling, Malek cautions that it can also interrupt the inflammatory process if done excessively. So, be sure to measure your time spent performing cold therapy and to not exceed 20-30 minutes maximum, as well as to stop the therapy after a few days have passed to avoid hindering recovery.
When Should You Use Heat Therapy to Soothe Muscles?
Heat therapy is best used when treating injuries after 72 hours have passed. If it's a relatively minor injury such as a strain (ie. not a tear or broken bone), then start utilizing heat therapy to treat pain and get the blood flowing in the muscles.
“Be sure to check the skin and take precautions by adding layers between the heat and skin, especially if sensation is impacted,” Malek suggests.
This ensures that the affected areas and surrounding soft tissues remain safe and secure. After three days, apply heat to reduce pain and help loosen muscles, but don’t apply heat for more than 20 minutes at a time, Daly says, to avoid developing a skin rash or getting burned.
After three days have elapsed and you've used heat to address your pain, you can also increase the use of light stretching and foam rolling as two additional recovery procedures.
“I recommend getting a heating pad and applying it to the injured muscles for about 15-20 minutes before foam rolling, to then follow it up with some light stretching,” Malek says.
The Verdict on Heat and Ice Therapy
Though time may vary based on the individual and injury, a general rule is to continue to treat an injury for three to five days following its onset.
“If you can act on it by adding compression, protecting it, and moving the injury as early as you can, you capitalize on the healing process,” Malek says. “Once you feel less swelling and are ready to get it moving, using heat for up to 10 minutes can help get things looser and prepared for movement and rehab."
The goal should be to get moving again in a way that is reasonably tolerable and primed for rehab exercise.
Safety Tips for Using Cold or Heat Therapy
Always check your skin right after applying heat or ice to make sure that there’s no irritation or adverse reaction before continuing use. (And of course, if there is, stop ASAP.)
You want to avoid excessively heating a freshly-pulled muscle because of the influx of inflammation to the area, and definitely avoid any open wounds. For a mild strain that just feels somewhat tight or painful, heat can be a good option for pain relief, but it may be fine with just some light movement, as well.
Remember to use compression and gentle movement for the best results. And while ice is beneficial to an extent, you want to avoid icing too much throughout the early stages of healing.
Sometimes Cold and Heat Therapy Aren’t Necessary
Sometimes you won't require either therapy. Instead, you may simply need a good recovery routine in place to warm up your muscles before training, to increase blood flow and muscular temperature, and to thus make your muscles more flexible and less prone to injury.
“Take note that not all sources of pain and muscle stiffness signify injury requiring cold therapy or ice, and a simple routine consisting of stretching and foam rolling — as well as recovery fuel, hydration, and sleep — should be enough,” Daly says.
You can certainly still use heat and cold therapy as part of prevention, though. Try cold therapy after exercising if you are in any pain — regardless of whether you have a real “injury” — and definitely if you notice swelling, too.
Finally, cold therapy should never be used before activity. While heat therapy can effectively be used before working out (along with foam rolling and stretching), using cold therapy prior to training can lead to further damage and injury. Remember that muscles need to be warmed up before exercising, and cold therapy does the opposite. Instead, simply try dynamic stretching for a few minutes before starting your workout.