Once or twice a week you go in for physical therapy for lower back pain. The therapist puts a heat pack on your back for a few minutes before the therapy and a cold pack on a few minutes after. Besides just feeling good, what are the hot and cold treatments doing? Here is how those procedures help your body and what you need to know to use them yourself at home.

How Heat Therapy Works

When heat is applied to the skin, the muscle tissue in the blood vessels reacts by expanding, which opens up the vessels. More blood flows into the area, bringing oxygen and nutrients. Waste materials are also moved quicker out of the heated area. Other muscles in the heated area react by expanding constricted muscle fibers. These reactions of your body to heat benefit you by:

• decreasing muscle spasms
• improving flexibility and range of motion
• getting rid of muscle stiffness
• reducing pain  
• increasing healing of damaged muscle tissue

Applying Heat Therapy

The heat can be moist, like a hot water bath, or dry, like a heating pad. Dry heat can dry the skin if used too long. The heat should be a constant temperature. Fluctuations cause the muscles to work to expand and contract with the changes. Sources for heat therapy include:

• electric heating pad
• microwavable heating pad
• hot water bottle
• heated gel pack
• heated whirlpool

Using Heat Therapy at Home

You can use heat therapy on stiff joints and joint pain, muscle spasms and sore muscles. Tips for using heat at home include:

• Wrap the heat source in a towel before applying to the skin.
• Apply heat only for a few minutes at a time.
• Don't use heat on swollen areas.
• Don't use heat on an open wound or incision.

How Cold Therapy Works

Blood vessels contract when the area is cooled down. This reduces the blood flow and makes muscle fibers shrink. This benefits you by:

• reducing inflammation in the area
• reducing muscle spasms
• reducing pain caused by the swelling

Applying Cold Therapy

Cold therapy is most often used in the first few hours after an injury to control inflammation. When used in combination with heat therapy, such as after your low back pain treatments, it relaxes your heated, active muscles. Sources for heat therapy include:

• ice pack
• cold gel pack
• cool water pad

Using Cold Therapy at Home

You can apply cold to sprains, strains, bruises, and overused muscles immediately after the injury to reduce swelling and pain. Tips for using cold at home include:

• Wrap the cold source in a towel before applying it on the skin.
• Cold is most useful during the first 24 to 48 hours after an injury when the swelling is most likely to occur, says Healthline.
• Apply the cold for 15 to 20 minutes, then remove and let the body temperature return to normal before reapplying.

Check with your doctor before using heat or cold at home if you have any questions about which is the best for a particular joint or muscle condition. Contact a group like Park Avenue Trauma Associates to learn more about physical therapy treatments.