Quiz: If you’ve just hurt yourself — for example, sprained your ankle or tweaked your shoulder hitting a tennis serve — do you ice the injury or apply heat to it?
Or how about chronic soreness or swelling from conditions like osteoarthritis or lower back pain? What’s more effective: heat or cold?
These are questions many people have, and a surprising number aren’t certain about the answer.
Cold Therapy vs. Hot Therapy: Guidelines
Understanding the effects of cold and heat on the body makes it easier to know when to use each.
Cold therapy (cryotherapy; for example, an ice pack, a sack of frozen peas, or soaking in an ice bath) has the following effects:
It narrows blood vessels, slowing the flow of blood to the injured area. The effect: reduced fluid and swelling.
It numbs nerve endings, which helps to minimize pain.
Applying ice to an injury is advantageous because it keeps swelling, stiffness, and pain under control. In certain cases, reducing swelling quickly can be critical because too much fluid around an injury site can cut off blood flow to surrounding tissue, damaging it. Additionally, if you need to move or put weight on the affected body part, icing it first can often help to keep it functional until you’re able to get to a safe place where you can lie down, rest, and seek further treatment if needed. For these reasons, ice therapy is often recommended as a form of first aid (think RICE treatment: rest, ice, compression, elevation).
Heat therapy (thermotherapy; for example, applying a heat pad or soaking in a hot tub) has the following effects:
It promotes circulation, meaning it aids the delivery of blood (and oxygen and nutrients) to the site of an injury. This can speed healing. However, excess blood at a fresh injury site can also contribute to swelling.
It helps remove lactic acid buildup in the muscles, relaxing them and taking away tightness and soreness.
It helps to manage chronic pain, discomfort, and stiffness affecting muscles and joints.
Applying heat is advantageous because it can soothe persistent aches and warm up tight tissue. Heat (oftentimes, moist heat) is usually advised as a way to treat and manage persistent or intermittent pain and stiffness or older injuries (for example, by applying heat after the first 24-72 hours of ice therapy).
Important notes to remember, There are situations where you’ll need to use both ice therapy and heat therapy. Many people with osteoarthritis, for example, benefit from alternating between the two. But generally, these rules apply:
Ice acute injuries.
Heat to treat chronic pain.
Remember, if you’re holding ice against an injury, to following these basic rules:
To avoid ice burns, never put ice or cold packs directly against your skin; hold the ice in a plastic bag or wrap it in a thin towel, like a paper or kitchen towel.
If your skin turns pink or red after the first five minutes, remove the ice.
Do not apply ice for longer than 20 to 30 minutes at a time. Lengthy exposure to cold therapy may actually slow your healing. Set a timer if needed.
5 Ways to Use Ice Therapy
First aid. Icing a soft tissue injury within five minutes of its occurrence is by far the most useful (and widely used) application of ice therapy. Bringing down the body temperature at an injury site has the effect of limiting the body’s response. Icing can slow bleeding and swelling under the skin. It can also prevent or control spasms and minimize pain.
Important note: In the case of minor sprains, strains, and bruises, you can practice RICE therapy on your own for 1 to 3 days (though seeing a physician or orthopedist is recommended to avoid further tissue damage).
Pain and swelling reduction after surgery. In some cases, applying cold packs over wound sites and stitches can help to relieve discomfort. For example, after childbirth, women who’ve undergone episiotomy or who have had vaginal tearing may get some relief from brief applications of cold.
Swelling reduction for arthritis. If you have flare-ups of swelling and joint stiffness, studies indicate that applying ice and/or using ice massage can help to reduce swelling and pain. It can also help to restore range of motion and improve muscle strength. Consult your doctor for advice on the best and safest way to use these techniques.
Acute lower back pain. Whether or not to use cold for lower back pain is a subject of debate. This is because lower back pain can have a multitude of causes. If your lower back pain involves trauma and inflammation, ice can help to bring down swelling and control your pain. For example, you may benefit from ice if you’ve strained your back lifting a heavy object or if you have whiplash. Icing the lower back can also help the pain and numbness of sciatica by reducing inflammation of the sciatic nerve.
Important note: If, as with most people, your lower back pain is not caused by inflammation, ice is probably not beneficial. Most other forms of lower back pain can be managed with heat therapy.
Sports medicine and rehab. With some injuries like ligament sprains or muscle spasms, you may benefit from a combination of progressive icing and stretching — either static stretches (like quad or hamstring stretches) or dynamic/kinetic stretches (where you move through a range of motion). Sometimes, you can even perform the exercises with ice packs secured to you.
However, take care: too much exposure to ice can make your muscles stiff, and numbing may lead you to do more than you can safely handle.
Unless you are experienced with this type of cryotherapy, you should not attempt it without the guidance and supervision of a physical therapist or sports medicine practitioner.
If you have diabetes or other chronic health conditions that may affect circulation (including your perception of temperature), you should consult with your physician before administering heat or cold.
Together, you and your doctor can coordinate a custom treatment plan that’s both helpful and safe.
Dr. Williams has been practicing orthopedic surgery in Corpus Christi since 1998. After graduating from Texas Tech hereceived his medical degree from the University of Texas at San Antonio. At the prestigious Campbell Clinic located at the University of Tennessee, Dr. Williams completed not only an Orthopedic Surgery Residency, but an additional year of Fellowship Training in Spine Surgery. Dr. Williams is dedicated to creating an excellent patient experience in the office or in the surgery suite.