I often get asked by my patients when they should use heat or cold therapy.
The short answer is that heat therapy is a vasodilator, causing blood vessels to become dilated or increased in size, and is used to increase blood flow to an injured area.
On the other hand, cold therapy is a vasoconstrictor, causing blood vessels to become constricted or decreased in size) and is used to decrease blood flow.
So, the correct answer is: It depends on the problem or injury.
We use ice for inflammation and acute injuries, such as an ankle sprain, and heat for stiffness and chronic conditions, such as arthritis and back pain.
Types Of Cold Therapy
- Cold packs or compresses
- Ice packs
- Ice bucket
- Ice massage using an ice cube
- Bag of frozen peas
- Plastic bag with crushed ice
RICE – Rest, Ice, Compression, and Elevation
RICE has always been the standard of care for acute sports injuries.
The application of cold can reduce blood flow to the area hence reducing swelling to the affected area. The rate of inflammation is slowed and there is less risk of tissue damage.
Recovery time will be much faster when ice packs are applied.
If you sustained an injury or trauma whether on the field or running on the treadmill, ice can be applied for 15-20 minutes every hour for 4-6 hours for pain relief and to reduce swelling.
It is most effective immediately after the injury and up to 48 hours.
Cold therapy can also act as an analgesic/anesthetic, or pain reliever, by numbing the area and slowing pain transmission to the brain.
Never apply ice directly to the skin since that can cause an ice burn.
Heat therapy will increase blood flow to the affected area. It is used to promote tissue healing, relax muscles, and reduce stiffness.
Heat is more effective for chronic conditions that cause muscle pain and joint stiffness, such as chronic low back pain or neck pain.
As with ice, heat is also used for pain management and to reduce muscle spasms. Heat therapy can also speed recovery from exercise by reducing the lactic acid build-upbuild up.
Types of Heat Therapy
- Hot shower or hot bath
- Hot packs
- Hot water bottles
- Electric heating pads
- Paraffin wax
- Hot stones
(We do not recommend a hot tub in that it is often too hot for treatment of a sports injury as well as back or neck pain)
With heat application, you have to make sure there is enough toweling between the skin and the hot pack to avoid burns.
Never leave heat on for more than 20 minutes. Also, make sure to never fall asleep with hot or cold packs on your skin.
When to Use Hot and Cold Therapy Together
Alternating hot and cold therapy, or contrast baths, are often used to reduce muscle soreness and fatigue after intense exercise.
Heat expands blood vessels, improving circulation, and the incoming flow of blood brings nutrients to help the injured tissues heal.
Ice therapy, which causes vasoconstriction, decreases blood flow and reduces inflammation that can cause pain.
Research is not clear whether contrast heat and cold therapy is any better than heat alone, cold alone, or stretching to reduce delayed onset muscle fatigue and soreness.
Is Heat or Cold Better for Neck and Back Pain?
Generally, we recommend ice for the first 24 to 48 hours (sometimes up to 72 hours if there was a direct injury) to reduce swelling and ease the pain.
When it comes to heating back muscles, it’s important to note that although a hot shower might feel good, the heat might actually be increasing inflammation by opening up blood vessels.
But if you have chronic pain, then you may benefit more by heating your back or neck with moist heating packs.
It’s important to avoid very hot temperatures so that you don’t burn your skin.
Heat can loosen stiff muscles, improve circulation and, unlike cold therapy, can make you feel more relaxed and calm.
Heat and ice combinations can also be used to reduce muscle spasms that cause pain.
Contraindications to Heat/Cold Therapy
- Poor circulation
- Open wounds
- Decreased sensation of the skin
- Sensory disorders
- Skin conditions, such as infection or dermatitis
- The skin is hot and inflamed
Cold therapy will reduce inflammation and is a useful treatment for acute conditions, such as shoulder pain, ankle sprains, and muscle strains.
Heat therapy will improve circulation and is a useful treatment for chronic conditions such as neck pain, back pain, and arthritis.
Physical therapy is always recommended to help get patients back to full recovery and doing the things they love.