which to apply - Heat or cold?

Which to apply: HEAT or COLD?

Physicians explain that any injury or pain involving soft tissues- skin and muscle- responds to heat and cold. Moreover, the more superficial the injury, the more likely it is to respond.

But how do you decide whether heat or cold works best for a specific condition? To remember which to apply may help understand what happens to the body following an injury and responds to heat and cold.

When skin muscles are injured, the body releases chemical substances that dilate blood vessels and boost blood flow into the injured area. These chemical substances also draw additional white blood cells into the area.

The increased blood flow serves several purposes. Red blood cells carry oxygen which injured tissues require to repair themselves and heal. White blood cells help fight infection and also help repair damaged tissues.

Applications of heat and cold affect how much blood flows into the injured area.

The action of heat and cold:

The application of heat accelerates both the dilation of blood vessels in the injured area and tissue repair. Heat also is believed to speed the release of endorphins and serotonin, biochemicals that help fight pain and calm irritated nerves.

The chemical substance that promotes healing also produces inflammation, the pain, redness, and swelling that typically accompany an injury.

The redness comes from increased blood flow to the area; the swelling occurs as fluid leaks onto the damaged tissue from tiny vessels called capillaries

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Cold effects are opposite to that of heat. Cold constricts blood vessels, limiting the amount of blood that reaches the injured area. In this way, cold can help stop bleeding and is the proper treatment for nosebleeds or cuts.

Cold also counters inflammation by reducing blood flow to the area and the chemicals responsible for inflammation. Thus, cold can alleviate the swelling and pain that accompany inflammation.

In addition, the application of cold to injured skin and muscle numbs irritated nerves, thereby relieving the pain. In the case of insect stings, constricted blood vessels help prevent the spread of toxins in the bite area.

Some simple rules:

Experts advise the following rule of thumb when deciding whether to apply heat or cold.
Apply cold in acute situations---conditions that come on suddenly and involve bleeding or inflammation. Apply heat for conditions that are accompanied by ache or stiffness.
In some situations, the most effective treatment is cold, first in the acute phase and then heat during the long recovery phase.
In treating a strained or sprained muscle, e.g., a physician recommends applying cold during the first 48 hours after the injury to reduce the swelling. After 48 hours applying heat speeds healing and eases pain.
Joints that are inflamed as a result of arthritis also can benefit from the application of cold and then heat.

Wet or dry?

After deciding which one to apply, the next question is how to apply it. Both heat and cold can be applied in wet or dry form. In general, wet heat and wet cold are more penetrating than their dry counterparts and can be applied for a shorter period.

Soaking in a hot bath, for example, can bring quick relief to someone suffering from a backache or other muscle ache.

Similarly, physicians recommend immediately plunging a minor burn under cool running water or placing a towel soaked in water over the burn to halt further damage to the tissue. Ice the dry form can be more effective than cold water in certain cases and easier to apply.

Whichever way heat or cold is applied, moist or dry, the general idea is to get it as close to the injury as possible.

Always use caution:

No matter what method is chosen, physicians warn people to exercise caution. Heating pads that may relieve pain in 10 to 15 minutes can cause burns when allowed to remain in place for an hour or more, especially at a high setting.
At the other extreme, ice or cold water applied too long can damage tissues by cutting off the blood supply. Doctors also warn that people with diabetes or any condition in which the hands or feet have lost sensitivity must be cautious when applying heat or ice.

Perhaps most important, experts emphasize that serious injuries of any kind should receive immediate medical attention from a health care professional!

https://www.scoi.com/patient-resources/education/articles/should-you-ice-or-heat-injury