Most people are familiar with using hot and cold treatments for pain, but did you know that not all heat is created equal? There are two different types of heat therapy: moist and dry. Both are meant to penetrate below the skin to relieve pain and soreness, but it’s important to know the benefits of each before choosing one to include in your physiotherapy treatment plan.
What is moist heat?
Moist heat therapy includes a wet heat source used to soothe and relax sore muscles, joints and ligaments. This could include hot water bottles, steam towels, hot baths, or moist heating packs. Hot baths can be especially helpful because the enveloping heat will target both the injured muscles and the ones that may have tensed up to compensate for your injury.
What are the benefits?
In comparison to dry heat (electric heating pads and heat wraps), moist heat can penetrate the skin faster and deeper, getting right to the muscle—the root of your pain. A study comparing the two types of heat therapy showed a greater pain reduction with moist heat in less time than dry heat. There’s also a reduced chance of skin irritation since the moisture helps to increase tissue elasticity.
Dry heat can provide a more consistent level of heat for a longer period of time. As a result, some see it as more convenient and easier to use.
How is it applied?
Any heating pads, whether they have water or gel inside, need a layer in between the source and your body to avoid burning the skin. You may see your physiotherapist using a hydrocollator, which heats pads in a thermostatically controlled water bath. The pads are put in covers before being placed on the injured area. Any source of moist heat should be monitored throughout to ensure the skin does not overheat.
You shouldn’t use heat therapy when the injured area is bruised, swollen or the skin is broken or hot to the touch.