At RestorEar, cooling is a big deal. Cold therapy, also known as cryotherapy, is one of the oldest and most widely used therapeutic strategies in medicine. From simple ice packs to advanced whole-body cryotherapy chambers, applying cold to the body has been shown to reduce pain, modulate inflammation, and support healing. But how does it actually work?

Here, we review the science of cold therapy, as well as some common and lesser-known applications.

The Physiology of Cold Exposure

When tissues are cooled, several key physiological changes occur:

• Vasoconstriction: Cold exposure narrows blood vessels, reducing blood flow to the affected area. This limits swelling and decreases recruitment of immune cells into tissues.

• Reduced Nerve Conduction Velocity: Cooling slows activity in nerve membranes, reducing the speed of pain signal transmission. This is why cold application has a pain-reducing effect.

• Decreased Metabolic Demand: By lowering tissue temperature, cold reduces metabolic activity of cells, which can help protect against secondary cell injury in cases of trauma .

• Inflammatory Modulation: Cold suppresses the release of pro-inflammatory chemicals, thereby decreasing inflammation and tissue damage.

• Delayed Muscle Soreness Reduction: In sports medicine, cold therapy may reduce delayed onset muscle soreness (DOMS) through a combination of vasoconstriction, reduced inflammation, and altered sensory perception.

Clinical and Practical Applications

Acute Musculoskeletal Injuries

Ice packs remain a first-line treatment for sprains, strains, and bruises. Applying cold within the first 24–48 hours after injury helps limit swelling and provides pain relief.

Sports and Exercise Recovery

Athletes often use cold-water immersion or cryotherapy chambers after strenuous activity. Evidence is mixed: some studies suggest reductions in soreness and improved recovery markers, while others show modest or temporary benefits.

Chronic Pain Conditions

In arthritis, tendonitis, and low back pain, localized cold application can help reduce flare-ups associated with inflammatory activity. Unlike heat therapy, which is typically better for stiffness, cold is most beneficial when pain is linked to swelling or acute exacerbations.

Post-Surgical and Post-Trauma Care

Cold therapy is widely used following orthopedic and soft tissue surgeries to reduce swelling and improve patient comfort. Some devices combine cold with compression for enhanced effect.

Migraine and Headache Relief

Cold applied to the head, neck, or scalp can constrict blood vessels and reduce pain. One study found that cooling the carotid arteries at the neck lessened migraine intensity in some patients. Products like ReBoundLite may help reduce pain associated with tension headaches. 

Traumatic Brain Injury (TBI)

Perhaps one of the most fascinating emerging areas for cold therapy is its potential role in managing TBI. Lowering core body temperature has been studied as a way to limit secondary brain injury after trauma. The idea is that hypothermia decreases metabolic activity and pressure in the brain. By reducing oxidative stress and inflammation, cooling may protect neurons from delayed cell death that typically follows the initial injury.

Hearing Health

We couldn’t write about cold therapy without mentioning hearing health. Studies have shown a variety of benefits to using cooling, targeted at the inner ear (cochlea), for preserving hearing. Cooling during cochlear implant surgery may preserve hair cells and residual hearing function by reducing inflammation and recruitment of immune cells to the inner ears following insertion. This may be improved further with post-surgical cooling centralized in the inner ear with products like ReBoundLite. Further, cooling with products like ReBound has been shown to have a protective effect against noise trauma via a similar mechanism. These devices are designed to specifically target the cochlea and reduce its temperature to a therapeutically beneficial range. Read more about cold therapy for hearing health here. 

Safety Considerations

While generally safe when used correctly, cold therapy carries risks if misapplied:

• Frostbite or Skin Damage: Avoid direct skin-to-ice contact; always use a barrier.

• Nerve Injury: Excessive or prolonged exposure can impair nerve function.

• Circulatory Risks: Individuals with Raynaud’s phenomenon, peripheral vascular disease, or hypersensitivity to cold should consult a physician before use.

Cold therapy is more than a simple comfort measure. It has well-documented physiological effects that make it valuable in both everyday health management and advanced medical care. From controlling inflammation after a sprain to being investigated as a neuroprotective strategy in traumatic brain injury, cryotherapy continues to evolve in scope and scientific credibility.

While an ice pack may never replace medical intervention for severe conditions, the expanding research into cold therapy shows its potential as a low-cost, non-invasive, and sometimes life-saving tool.

For more information on cold therapy, subscribe to our newsletter.