Reasons why pain and swelling happens in an injury and how long you should apply ice to relieve them

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Reasons why pain and swelling happens in an injury and how long you should apply ice to relieve them

Cold therapy has come a long way since its injury-healing powers were discovered by Ancient Egyptians ages ago. These days, cryotherapy enthusiasts continue to grow, including athletes, biohacking advocates and youth-seeking beauties all swearing by cryotherapy’s  therapeutic and aesthetic powers.   

While generally safe to use, there are some considerations in using cold therapy for injuries. Before plopping an ice pack on any part of your body, read this article as we discuss facts related to an injury and the use of cold therapy to relieve its symptoms.  

The 3 phases of injury 

Because it damages and destroys cells, an injury disrupts the transportation of oxygen-rich blood to your tissues. Without adequate supply of oxygenated blood, your body’s capacity to produce adenosine triphosphate (ATP), the energy-carrying molecules, is compromised. As a cell-nourishing molecule, ATP is highly vital for cell processes, more so in injury recovery.  

The good thing is that your body is designed to heal itself, and to do that, it has to go through the following stages:

Phase 1: Inflammation  

After you hit or bumped yourself, blood and fluids rush to the injured site in an attempt to protect it. Bleeding occurs if you have an open wound, while bruising happens typically around the injured site or when there’s no way for blood to exit from your body. 

Shortly thereafter, your body releases chemicals that allow the blood platelets to stick to the exposed parts of the tissues, creating a plug in an attempt to stop the bleeding.   

 As white blood cells rush to the injured site, fluids from the blood vessels leak into the surrounding tissues, producing the early and obvious signs of inflammation: swelling, redness and warmth. 

At this stage, the body’s cells send pain signals to the brain and you may feel either a numbing or debilitating pain, depending on the type of injury you have. The initial inflammation phase takes four to six hours after the trauma, making it the best time to apply cold therapy or ice packs, if you don’t have an open wound. 

Towards the end of the inflammatory phase, specialized protective cells called monocytes work to clean up the dead cells and other unwanted matters at the injury site. 

Phase 2: Reparation

Chemicals that facilitate long-term healing from injuries are released during this phase. As the cells begin the reparative process, they create an extracellular barrier that mixes with high collagen levels, forming scar tissue.  

The process of creating scar tissues for injury reparation starts within the first two days and can last for several weeks or months.  

Phase 3: Regaining strength and flexibility 

This period marks a critical phase in regaining strength, function and flexibility. Hence, it is advised to condition your body by performing stretches, exercises and seek physical therapy, if needed. 

Do not push your body too hard, though, because the injured site, along with the surrounding muscles and tissues, remain susceptible to reinjury at this stage. 

Depending on the location and severity of the injury, this process may last for several weeks to months, so you definitely don’t want to cause another trauma or aggravate your condition.  

Why does pain and swelling happen after injuries?

Swelling may be considered as the first step to the healing process. Heat, redness and swelling are signs of inflammatory response and clear signals that your body is working to repair itself. 

A rush of blood to the affected area results in redness and heat, while increased movement of fluids and white blood cells to the injured site causes swelling. Nerve compression and the release of various chemicals, meanwhile, trigger pain and discomfort. 

How does cold therapy help ease an injury?

Cryotherapy is most effective when used exclusively to an injured area within 48 hours following an injury. It slows down the receptors that send pain signals to the brain, creating an analgesic effect. Ice also helps control the swelling by narrowing blood vessels to reduce the bleeding, rushing fluids and cellular metabolism. Keeping unwanted cells and debris to a minimum also means shorter recovery time.  

How long should ice be used on an injury? 

There is no doubt that soft tissue injuries, swelling and pain go hand in hand. As such, the injured area will be most painful and swollen within 24–48 hours after an injury.  

Ice or cold therapy should be applied within two days or the first 48 hours following an injury to maximize its anti-inflammatory benefits. Each application should last no more than 20 minutes, and can be repeated for at least four times in a day.  

Chronic inflammation, or one that stretches for weeks on end, could be an indication of a more serious medical issue. If this happens, visit your doctor for proper diagnosis.  

Which cooling tools can be used for an injury?

Applying cold therapy immediately after an injury and up to 48 hours thereafter is easy if you have these icing tools:  

Reusable ice packs

They come in all shapes and sizes, some with built in compression and sleeves. If you’re often injured in a specific  body part, buy a specially-designed ice pack for it. We find that applying cold therapy to an injured  or painful leg is a challenge, and this leg ice pack does the job perfectly. 

If you have frequent aches and pains everywhere, try this multipurpose ice pack that fits anywhere in your body, and can be used hot or cold.

Instant ice packs

They’re must-haves in your first aid kit and are great for emergency use, for instance, when accidentally hurting yourself while exploring the great outdoors.  

Ice baths

Immersing in ice cold water might not be your idea of therapy, but athletes have been doing this for years to heal faster from injuries and improve performance.  

DIY ice packs

No reusable ice pack? No problem. Fill your ice cube tray, plastic resealable bags and paper or plastic cups with water and freeze. The downside for this type is that they melt rather quickly. 

Is icing an injury bad? 

Applying cold therapy to an injury is generally safe as long as you take the necessary precautions to avoid an ice burn or frostbite. 

Put a thin cloth in between your skin and the pack, especially if you’re using a DIY ice pack, and do not place it on your skin for more than 20 minutes to prevent tissue damage. 

Individuals with sensory and circulatory issues such as diabetes, multiple sclerosis or Raynaud’s syndrome, among others, should not engage in temperature therapy. 

Is ice or heat better for injuries?

The general principle is to use cold therapy for acute soft tissue injuries and heat for  chronic pain and stiff muscles. As a vasodilator, heat promotes blood flow to the injured site, making inflammation worse. 

Cold therapy is most effective when used within the first two days (or 48 hours) following an injury. After this period, you may apply heat to open up the blood vessels and ease stiff, knotted tissues and muscles. 

The best option, though, is to alternate the use of cold and hot therapies. Also called contrast therapy, switching from cold to hot packs (and vice versa) creates a powerful pumping action that facilitates the rush of oxygen and nutrient-rich fluids to the injury site, accelerating healing. 

Other methods to relieve soft tissue injuries 

Besides ice pack application, these strategies could help you get back on your feet, stronger than ever, in no time. 

  1. Protect the affected site and nearby tissues from further injuries by using supportive devices such as slings, splints, crutches, canes or walking sticks, depending on the location of your injury. 
  2. While you are advised against performing activities that could exacerbate your condition, this does not mean that should not move at all. It’s better to do simple stretches or non-weight bearing exercises, such as swimming, biking or walking, to prevent muscle atrophy.  
  3. Compression, or adequate pressure on the injury site, decreases swelling and facilitates healing by keeping unwanted fluids away from the injury site. If you have an ice pack that does not come with an elastic bandage, consider buying one to apply cold compression and heal from an injury at a faster rate.  
  4. It is important to keep the injured site elevated so that blood and other fluids do not pool around the injury. Unabated fluid build up can lead to pain, potential blood clot, and delayed recovery.

If your symptoms continue to worsen despite these methods, have yourself checked by a doctor. 

Hi, I’m Steve Stretton, owner and manager at Do you find ice packs effective for your injuries? Share your thoughts in the comments section below or write to us here.

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