While soaking in a hot tub or lying on a heating pad simply feels good, especially if your muscles ache after a hard run, this warming can do more than offer relaxation. In fact, science backs up the use of heat therapy in an athlete’s routine.
“Heat has its uses and its benefits,” Leo Arguelles, P.T., D.P.T., assistant clinical professor in the Department of Physical Therapy at the University of Illinois Chicago and spokesperson for the American Physical Therapy Association, tells Runner’s World.
For one, using heat therapy can alleviate the severity of delayed onset muscle soreness (a.k.a. DOMS, the soreness that occurs hours after an especially tough workout). It can also help runners manage certain injuries and find relief from stiff muscles and joints. The benefits of heat therapy are relevant to all runners, no matter their mileage or speed.
Here, we explain all you need to know about heat therapy, including what it is and its benefits, plus how to use it for maximum effectiveness. We also explain when heat therapy isn’t the right remedy.
What is heat therapy and how can you create it for yourself?
Just as the name implies, heat therapy is using warm or hot temperatures to treat injuries, or sore muscles and joints.
There are two categories of heat therapy: wet heat therapy and dry heat therapy, says Arguelles. The former involves moisture, including hot tubs, hot showers, and steam baths. The latter includes non-wet tools, such as hot packs, heating pads, heated massage guns, and hot water bottles. In general, wet heat therapy targets large surface areas of the body–like your entire lower half, for example–whereas dry heat therapy hones in on smaller areas, such as the knee joint.
You can experience heat therapy at home by simply soaking in a hot bath or shower. Alternatively, you can place a heating pad or hot water bottle on your hip, calf, or other part of the body. You can also access some types of wet heat therapy, including hot tubs and steam baths, at gyms and spas.
Physical therapists and other fitness professionals frequently offer heat therapy as part of their treatment, Brett Toresdahl, M.D., primary sports medicine physician at the Hospital for Special Surgery (HSS) and research director for HSS Primary Sports Medicine Service, tells Runner’s World. “A physical therapist often has equipment that can apply heat to a larger area and maintain a more constant temperature than what someone can do on their own,” he explains.
What are the benefits of heat therapy?
First things first: Heat therapy isn’t a cure-all for your aches and pain, but it does offer benefits beyond just feeling good.
There is some evidence that heat therapy can alleviate the effects of DOMS, says Arguelles. Indeed, a 2021 meta-analysis published in the journal Physical Therapy in Sport, which included 32 randomized controlled trials and more than 1,000 patients, found that using heat therapy within one hour of exercise can lessen the pain of DOMS and that using a heat pack in particular can promote recovery from DOMS. The researchers also concluded that cold water therapy can provide similar effects, stating that we need more research to determine is one method is more effective than the other.
While heat probably won’t eliminate DOMS completely, “it helps take a little bit of that edge off,” says Arguelles. This can help runners feel more comfortable and motivated to resume their usual running routine, he explains.
Heat therapy can also provide temporary relief for stiff muscles and joints, says Toresdahl, allowing you to move and run more comfortably. That means you could use heat therapy to help you warm up and get loose before you start a run. (However, it’s probably even smarter to do dynamic stretches and exercises before a workout versus heat therapy, as these types of active movements will more effectively prime your body to run, says Arguelles.)
Additionally, runners can use heat therapy to treat certain injuries, such as a strained calf or hamstring, or manage chronic orthopedic conditions, like early osteoarthritis of the knee, Toresdahl adds. In the case of injury, heat therapy can promote blood flow and nutrient circulation to accelerate healing and also tamp down pain by relaxing tight muscles, according to the Mayo Clinic.
A 2021 study published in the journal Clinical Nursing Research involving 117 patients, demonstrated that localized heat therapy was effective in improving pain and joint function in people with knee osteoarthritis. (The study also found a cold rub gel to be similarly effective.)
If you’re using heat therapy to treat an injury, keep in mind that heat therapy alone likely won’t resolve your issues, says Toresdahl. “However,” he adds, “if it is not too much of a hassle to do, heat may help an injured muscle or joint feel better so that it is easier to gradually return to exercise or perform a rehab program.”
When and how should you use heat therapy?
There’s no one-size-fits-all guidance for the frequency and duration of heat therapy sessions. “Some may find that five to 10 minutes of heat on a recently strained hamstring is all that is needed to get it feeling good and ready for a little strength training or a rehab session,” says Toresdahl. “Others find a regular routine of 20 to 30 minutes of heat in the evening helps alleviate joint soreness that builds up throughout the day.”
Generally speaking though, if you’re using heat to treat soreness and stiffness following a workout, or to treat an injury, aim for 15 to 20 minutes of heat application (via a heating pad, hot tub, or hot shower), says Arguelles. If you’re using heat therapy to warm up a joint or muscle, you can probably get away with just five to 10 minutes of application.
Try to schedule a heat therapy session within the first 24 hours after a tough workout to offer up the soreness-easing benefits, Arguelles says.
What are the downsides of heat therapy?
Heat therapy isn’t recommended for all scenarios. For example, if you have “swelling and sometimes warmth of a joint or tendon,” says Toresdahl, such as a recent ankle sprain, heat may not be helpful.
When you do have swelling, applying heat may only increase the inflammation and exacerbate any pain you’re already feeling, says Arguelles. Instead, ice the area to help reduce the swelling. Once the swelling and inflammation has subsided, use may use heat to help warm and loosen that area prior to exercise.
Likewise, an open wound does not typically respond well to heat.
Also, use caution with heat therapy if you’re:
- Living with a condition in which it is difficult to detect temperature, such as diabetes or peripheral vascular disease
What else should you know before trying heat therapy?
“As with any treatment, it’s possible to overdo heat therapy,” says Toresdahl. “Applying something that is too hot for too long can cause a minor burn injury to the skin.”
When using heat therapy, check your skin after five minutes for excessive redness or any breakdown in the skin, says Arguelles. If you notice either sign, or if the heat simply feels painful against your skin, then turn down the heat, place an extra barrier between your skin and the heat source (for example, wrap a towel around a hot water bottle), or stop the heat therapy session entirely, he says.
If you’re using a hot pack or hot water bottle wrapped in a towel, note that it may not feel very warm at first. Wait a few minutes for the heat to seep through before dialing up the temperature, Arguelles cautions. Additionally, when using a hot pack, avoid strapping it onto your body as that can decrease circulation, he warns. Simply rest the pack on top of the area you’re targeting.
If you’re dealing with a new injury, your best bet is to see a physical therapist to get a tailored program to address the injury. They may prescribe a combination of heat therapy and icing as well as strength, mobility, and form correction work, says Arguelles.
The bottom line on heat therapy
Keep your expectations about heat therapy in check. Yes, heat therapy has science-backed benefits, but it should be used in tandem with other recovery activities—like stretching and mobility work—as well as a consistent exercise routine to ensure you’re not overstressing your muscles and joints.
Jenny is a Boulder, Colorado-based health and fitness journalist. She’s been freelancing for Runner’s World since 2015 and especially loves to write human interest profiles, in-depth service pieces and stories that explore the intersection of exercise and mental health. Her work has also been published by SELF, Men’s Journal, and Condé Nast Traveler, among other outlets. When she’s not running or writing, Jenny enjoys coaching youth swimming, rereading Harry Potter, and buying too many houseplants.