What Does Cryotherapy Actually Do to Your Body?

It's the question we get asked more than any other. Not "how cold is it?" or "does it hurt?" — but the honest one underneath all of it: what is this actually doing to me?

Three minutes in a chamber at around −120°C is a genuinely extreme thing to ask of your body. So it's fair to want to know what's happening on the inside while you're standing in there. This is the straight answer — what the science supports well, what it supports loosely, and what's still being worked out. No miracle claims. Just physiology.

First, what your body thinks is happening

Your skin is covered in cold receptors, and at around −120°C they all fire at once. Your body can't tell the difference between a cryotherapy chamber and a genuine survival threat, so it does what it's built to do: it protects the core.

That single reflex is the engine behind almost every effect people describe. Everything below flows from it.

1. Your circulation does a rapid switch

The moment the cold hits, blood vessels near the surface of your skin clamp down — vasoconstriction. Blood is pulled away from your arms, legs and skin and redirected to protect your vital organs in the core.

Then you step out. As your body rewarms, those vessels open back up — vasodilation — and freshly oxygenated blood rushes back out to the tissues it had abandoned.

That constrict-then-flush cycle is the most reliable, well-documented thing cryotherapy does. It's also the mechanism most of the recovery benefits are thought to hang off.

2. A sharp noradrenaline surge

This is one of the most consistently measured effects in the research. Cold exposure triggers a significant release of noradrenaline (norepinephrine) — a neurotransmitter tied to alertness, focus, mood and energy.

It's very likely the reason people walk out feeling switched on and clear-headed rather than sluggish. This one shows up across studies reliably enough that it's fair to call it a real, repeatable response — not just a placebo glow.

3. It calms the inflammatory response — mostly

Several studies have found that whole-body cryotherapy lowers pro-inflammatory markers in the blood, and a 2025 meta-analysis pooling eleven randomised controlled trials concluded it can reduce the body's inflammatory response.

Being honest, though: it's not unanimous. Some trials have found no meaningful difference against a placebo. So the fair summary is promising and trending positive, but not settled. If anyone tells you cryotherapy is a guaranteed anti-inflammatory cure-all, they're ahead of the evidence.

4. It genuinely dulls pain

Cold slows the speed at which your nerves conduct signals and raises your pain threshold. This is basic, uncontroversial physiology — it's the same reason ice works on a sprain, scaled up to your whole body.

That short-term analgesic effect is real. Where you have to be careful is the leap from "reduces pain in the moment" to "treats a chronic pain condition." Research is exploring cryotherapy for things like fibromyalgia and arthritis, but regulators have been clear that it is not a proven treatment for any specific disease. Relief in the moment is not the same as a cure, and we won't pretend it is.

5. It helps how recovery feels after training

For athletes, the strongest and most repeated finding is this: cryotherapy improves perceived muscle soreness and subjective recovery after hard training.

The nuance worth knowing: the evidence that it speeds up actual measured functional recovery — how much power your muscles can produce the next day — is much thinner. In fact, one well-known review pointed out that cheaper options like an ice bath or cold-water immersion may deliver comparable physiological effects.

So the honest version is: people reliably feel less wrecked and recover more comfortably. That subjective benefit is real and it matters. Just don't expect it to rebuild torn muscle fibres faster than the biology allows.

6. Sleep and mood

There's a growing body of preliminary research here, and it's genuinely interesting — but it's early.

On sleep, some studies report improved quality, plausibly linked to the shift toward parasympathetic ("rest and recover") nervous system activity after a session.

On mood, small studies have shown promise for cryotherapy as an add-on for low mood and depressive symptoms, with some pointing to increases in BDNF, a protein tied to brain health. The researchers themselves are consistent on one point: these are early, small studies, and larger trials are needed before anyone should treat this as established.

We'll flag it as a hopeful area to watch — not a promise.

7. The metabolic angle (and why "weight loss" gets oversold)

Cold exposure activates brown fat and appears to switch on some exercise-like signalling in the body, which is why researchers are curious about cryotherapy's role in metabolic health. It's a legitimate and active research frontier.

But this is exactly where the industry tends to overreach. Regulators have specifically named weight loss as one of the claims that isn't backed by evidence. A three-minute session is not a shortcut around diet and training. If you see cryotherapy sold primarily as a fat-loss tool, be sceptical.

The honest bottom line

Here's what a fair reading of the science actually says:

Well supported: the circulation shift, the noradrenaline surge, short-term pain relief, and improved perceived recovery and comfort after exercise.

Promising but not settled: reduced inflammation, better sleep, and mood benefits — all trending positive, all still needing larger and better trials.

Not proven — treat claims with suspicion: curing specific diseases, and using it as a weight-loss method.

Cryotherapy is a powerful physiological stimulus with real, measurable effects. It is not a cure for anything, and no whole-body cryotherapy chamber is approved as a medical treatment for a specific condition. Anyone selling it as a fix for illness is stretching well past the evidence — and we'd rather you heard that from us.

Who should be cautious

Because it's a real stress on the cardiovascular system, cryotherapy isn't for everyone. It's generally not recommended if you're pregnant, have uncontrolled high blood pressure, significant heart or circulatory conditions, a recent cardiac event, cold allergy or cold-sensitivity conditions such as Raynaud's, or certain other health conditions. If any of that applies to you — or you're simply unsure — talk to your doctor before your first session. A good operator will always screen you first.

One thing worth knowing about the chamber itself

Not all cryotherapy is delivered the same way. Many chambers around the world are cooled with liquid nitrogen, and that method carries a specific, documented risk: nitrogen vapour can displace oxygen in the chamber, which is why the serious safety incidents you may have read about are almost always tied to nitrogen systems.

Every KRYO KUBE chamber is 100% electric. There's no nitrogen, no gas, and nothing to displace the air you're breathing — you're standing in genuinely refrigerated air, the same principle as any other cooling system, just far colder. It's a cleaner, more controlled way to get the same deep cold, and it takes an entire category of risk off the table.

That's not a wellness claim. It's just how the machine works.

This article is general education about how the body responds to cold, not medical advice, and cryotherapy is not a treatment for any specific medical condition. Always speak with a qualified health professional about your own circumstances before starting.

KRYO KUBE — Australia's first 100% electric whole-body cryotherapy chambers.