When to Use Heat—and When to Use Ice—for Sore Muscles, Back Pain, and More

Chances are if you’ve been injured, struggle with low back pain, or have sore muscles from exercising, someone has advised you to throw on an ice pack or a heating pad to help decrease pain, inflammation, or stiffness.

Heat and ice work in very different ways to help ease discomfort and promote recovery. Ice or cold therapies numb the area and constrict the blood vessels, causing less circulation to the area and generally decreasing any swelling. Heat, on the other hand, increases the blood flow and loosens up the surrounding joints and muscles.

Not every ache and pain should be treated exactly the same way, so the guidance for when to use which modality—hot vs. cold—isn’t always the same either. 

So how do you know when to use heat and when to use ice for sore muscles, back pain, or other common aches and stiffness? We spoke with an orthopedic surgeon and a physical therapist to break down when, where, and how long to use each modality.

Using Heat and Ice Safely

First and foremost, when using either ice or heat for warm up or recovery, there are a few precautions to keep in mind. You never want either source to have direct contact with your skin because too much ice can cause frostbite or too much heat can cause a burn. 

Icing best practices: With ice you want to make sure to have something like a  towel or a pillowcase wrapped around the ice pack (frozen peas work great, too). Some of the higher-tech cold delivery products you may see at a physical therapist or doctor visit can actually regulate the temperature to make sure you aren’t getting a cold burn, but most don’t have those available for home application. 

Heat best practices: With heat you’ll want to make sure it’s warm, but never scorching hot. If it’s hotter than warm, it’s recommended to have multiple layers between the heat source and your body—something like a towel, a shirt and a sweatshirt would be appropriate.

How Long to Apply Heat and Ice

The general rule of thumb for both ice and heat is 20 minutes on, and 20 minutes off. There are some exceptions like the lower level heat portable heating pads that are made to use all day. 

It’s important to consult your doctor before using heat or ice if you have cardiac issues or hypertension as both ice and heat have an impact on your blood vessels. This is especially important with some of the full body modalities like cryotherapy or infrared sauna that change the temperature of your entire body.

It’s a must to consult your doctor if you have any sensory deficits as well. “Nerve damage, stroke, spinal cord, or brain where the sensory nerves can be impacted can be unsafe,” says Kris Ferrara, DPT, a physical therapist at Moss Rehab in Philadelphia. “If you don’t feel temperatures or sensations in a normal way (or don’t feel them at all) it can be quite dangerous and something to consult your doctor about."

Post-surgery, ice is ideal to reduce severe inflammation.

When you first get out of surgery and everything is extremely swollen, ice is often the appropriate modality to reduce the swelling enough to where you can move the limb or injured body part.

“I tell my patients after surgery to ice as often as they can, when they have the most swelling and inflammation,” says Thomas Hickernell, MD, an orthopedic surgeon at Greenwich Hospital in Greenwich, Conn.

This period is usually around 48 hours, but again, always follow the instructions of your physician. The goal, however, is to get moving and healing as soon as you’re able to, which requires proper blood flow, so after that initial 48-hour period of severe inflammation, you’ll usually be told to ease back on the ice.

Acute injury doesn’t always require ice like we used to think.

Remember following the R.I.C.E. (Rest, Ice, Compression, and Elevation) advice for recovery? That guidance is no longer followed when it comes to any injury, and over the years the acronyms have evolved. 

Most recently, it’s best to follow P.E.A.C.E. and L.O.V.E.: Protection, Elevation, Avoid Anti-Inflammatory Drugs, Compression, and Education; and Load, Optimism, Vascularization, and Exercise.

Why the shift? Doctors started to see that rest and ice were actually prohibitive in the healing process, which again requires lots of blood circulation to the wounded area. “Now we’re saying to let the body run through the inflammation process,” says Ferarra.

Ice may feel good for patients in the short term, but according to a 2021 article in the World Journal of Clinical Cases, “[w]hen the edema (swelling) level is not severe (e.g muscle tear), cold therapy may not be helpful, but rather act as a barrier to recovery.”

You won’t hear heat as a recommendation at this stage either. “There is already inflammation during the healing process and we don’t want the heat to increase it more,” Ferrara explains.

For less serious aches and pains, go with personal preference.

Feeling achy in your lower back or dealing with soreness from a pulled muscle? Once you’re past the initial phase of healing an injury (if there was one), the choice to soothe with heat or ice comes down to what you prefer in the moment and for your particular circumstances. Evidence from clinical trials is sparse on which modality actually decreases pain or inflammation in the long term, and as better technology comes out, more studies are certainly needed.

Dr. Hickernell always recommends listening to what feels best for your body, as long as you are being safe temperature-wise. 

Heat before, ice after.

A commonly recommended strategy is to use heat before activity to loosen and warm up. “Heat makes people relax and feel more loose,” Ferrara says. “Before a workout, throw some heat on it—it will help you move more easily.” Of course, make sure to do a warm-up prior to your workout to get the blood flowing to that area through movement. 

Then use ice where needed after activity, “to decrease the follow-up swelling,” Dr. Hickernell adds. The most important thing is listening to your body. If something is causing more pain, always consult your doctor on the best way to proceed.