Cryotherapy vs Cold Plunge: What the Data Shows

Key insights

  • The two protocols are not the same dose delivered two ways. Whole-body cryotherapy holds dry skin in air below minus 100 degrees for two to four minutes; a cold plunge holds the body in water near 10 degrees for five to fifteen. Water conducts heat roughly twenty-five times faster than air, so the colder-sounding number moves far less heat out of you.
  • The Cochrane review of cold water immersion pooled 17 trials and 366 participants and found lower muscle soreness against passive rest at every time point measured: a standardised mean difference of minus 0.55 at 24 hours, minus 0.66 at 48 hours and minus 0.93 at 72 hours 1.
  • The parallel Cochrane review of whole-body cryotherapy found only four small laboratory trials covering 64 participants, judged every outcome to be very low quality evidence, and concluded that the evidence is insufficient to support its use. Every confidence interval also contained the possibility of no benefit, or of more pain 2.
  • Where the two have been compared directly, cold water has generally come out ahead. In a randomised crossover trial after eccentric hamstring work, cold water immersion produced a very likely moderate advantage over whole-body cryotherapy for countermovement jump recovery at 72 hours, with effect sizes of 0.63 and 0.68 3.
  • In 31 marathon runners, whole-body cryotherapy performed worse than cold water immersion on muscle function, soreness and several blood markers, and neither modality outperformed a placebo control 4.

Cryotherapy chambers market themselves on a single number. Minus 110 degrees, sometimes minus 140, against the 10 or 12 degrees on a plunge chiller. Stated that way the comparison looks settled before it starts, and most people conclude that three minutes in the chamber must be doing something the tub cannot.

It is the wrong number to compare. Air temperature and water temperature are not interchangeable units of cold, because the medium determines how fast heat actually leaves the body. Water has a thermal conductivity roughly twenty-five times that of air and carries heat away by convection as it moves across the skin. Dry air at minus 110 degrees cools the outer millimetres of skin very quickly and very dramatically, then runs out of capacity. Water at 10 degrees keeps drawing heat from the limb for as long as you stay in it.

That physical difference shows up in the evidence base. The two modalities have been reviewed by the same organisation, using the same methods, within three years of each other, and the two reviews reached noticeably different conclusions. What follows is what each one found, what happened when the two were tested head to head, and how to think about the choice if you are deciding where to put money.

What each protocol actually does to the body

Whole-body cryotherapy involves standing in a chamber or cabin filled with extremely cold dry air, typically below minus 100 degrees Celsius, for two to four minutes 2. Partial-body systems use a cabin that leaves the head outside the cold air. The skin cools sharply, the cutaneous cold receptors fire, and there is a strong sympathetic response. What does not happen, in most protocols, is a meaningful drop in deep muscle temperature, because the exposure ends long before the cold penetrates.

Cold water immersion works on the same receptors but with a very different thermal profile. Water at 10 to 15 degrees produces a slower, deeper and more sustained fall in tissue temperature, along with hydrostatic pressure on the immersed limbs, which cryotherapy chambers cannot reproduce at all. A crossover trial that measured both approaches directly, using thigh muscle oxygen saturation, cutaneous vascular conductance, mean arterial pressure and skin temperature over the hour after treatment, compared 10 minutes of water at 10 degrees against a partial-body protocol of 30 seconds at minus 60 degrees followed by two minutes at minus 135 degrees 5. The point of that design is worth noting: two minutes at minus 135 degrees is considered roughly equivalent to ten minutes in cold water, not obviously superior to it.

What the data shows for cold water

The Cochrane review of cold water immersion is the reference point. Pooling 17 trials and 366 participants, it found lower self-reported muscle soreness after immersion compared with passive rest or no intervention, with standardised mean differences of minus 0.55 at 24 hours, minus 0.66 at 48 hours, minus 0.93 at 72 hours and minus 0.58 up to 96 hours 1. Those are moderate effects, consistent across the recovery window, and the confidence intervals did not cross zero.

The review was explicit about its limits. The included trials were small and carried poor methodological quality relating to randomisation, allocation concealment and blinding of outcome assessors, and there was insufficient evidence to draw conclusions about other outcomes 1. This is a reliable finding about perceived soreness, not a licence to claim cold water repairs tissue faster.

What the data shows for whole-body cryotherapy

The parallel review of whole-body cryotherapy, published three years later by an overlapping author group, found four laboratory trials reporting on 64 physically active young adults, of whom all but four were male 2. The pooled soreness estimates pointed in the right direction, with a standardised mean difference of minus 0.77 at one hour, minus 0.57 at 24 hours and minus 0.58 at 48 hours, but each confidence interval also included no difference between groups or a benefit in favour of the control condition. Every outcome was graded very low quality.

The conclusion was that the available evidence is insufficient to support the use of whole-body cryotherapy for preventing or treating muscle soreness, that there is no evidence at all in women or elite athletes, and that the best prescription and its safety are not known 2. The reviewers flagged separately that none of the four trials carried out active surveillance of adverse events, which they considered important given that the exposure involves an extreme temperature.

Head to head: what happens when both are tested in the same people

Two trials are worth reading closely. In the first, ten physically active men performed five sets of fifteen single-leg eccentric hamstring repetitions and then received, in randomised crossover order, either ten minutes of cold water at 10 degrees or three minutes of whole-body cryotherapy at minus 110 degrees. Creatine kinase, eccentric and isometric strength, jump performance, soreness and perceived recovery were tracked afterwards. The result was a very likely moderate effect in favour of cold water for single-leg and two-leg countermovement jump at 72 hours, with effect sizes of 0.63 and 0.68 3.

The second is more uncomfortable for both modalities. Thirty-one endurance-trained men ran a marathon and were randomised to cold water immersion, whole-body cryotherapy or a placebo, with soreness, muscle function and blood markers assessed before and at 24 and 48 hours afterwards. Cryotherapy came out worse than cold water on muscle function, perceived soreness and several blood parameters, directly contradicting the claim that it is the superior option. But the more important finding was that neither treatment beat the placebo control 4.

Realistic expectations

Read together, the picture is not that cryotherapy is a fraud and cold water is a cure. It is that cold water immersion has a substantially larger and more consistent body of controlled evidence behind a modest, real effect on how sore you feel, while whole-body cryotherapy has a thin evidence base, no data in women or elite athletes, unquantified safety, and no demonstrated advantage in the trials that have compared the two directly.

There is also a practical asymmetry that the studies do not measure. A cryotherapy session requires a facility, an appointment and a per-visit fee, which means the protocol is dictated by someone else's opening hours. A plunge at home is available every day, and adherence over months is what determines whether any recovery practice does anything at all. Set against that, the honest case for the chamber is convenience for people who will not tolerate immersion, and a genuinely different subjective experience rather than a superior physiological one.

Practical guidance

If soreness management is the goal, the protocol with the evidence behind it is water between roughly 10 and 15 degrees for five to fifteen minutes, applied after the session that caused the damage 1. Colder is not better; the pooled data do not reward extreme temperatures, and the practical ceiling on how long you will stay in falls sharply below 10 degrees. We have written separately on what the research recommends for cold plunge temperature.

Two caveats matter more than the choice of modality. Cold applied habitually after resistance training carries a cost to adaptation, so timing it away from the sessions you are trying to grow from is more consequential than whether the cold arrives as air or water. And the marathon trial is a reminder that expectation is doing meaningful work in every recovery protocol; that is not a reason to dismiss the practice, but it is a reason to be sceptical of any modality sold primarily on the size of its temperature number.

The Contrast Market Perspective

The effect sizes in this literature are moderate and they are tied to a specific dose: a stable temperature, held for a known duration, repeated consistently. A chiller that drifts several degrees between sessions, or a tub that is unpleasant enough that you stop using it in February, does not deliver the protocol the trials tested. That is the whole argument for buying equipment on temperature stability, recovery rate and build quality rather than on headline specifications. If you would like help matching a plunge to your space, water volume and climate, Schedule a consultation.

References

Footnotes

  1. Bleakley C, McDonough S, Gardner E, Baxter GD, Hopkins JT, Davison GW (2012). Cold-water immersion (cryotherapy) for preventing and treating muscle soreness after exercise. Cochrane Database of Systematic Reviews. PubMed ↩︎
  2. Costello JT, Baker PRA, Minett GM, Bieuzen F, Stewart IB, Bleakley C (2015). Whole-body cryotherapy (extreme cold air exposure) for preventing and treating muscle soreness after exercise in adults. Cochrane Database of Systematic Reviews. PubMed ↩︎
  3. Abaidia AE, Lamblin J, Delecroix B, Leduc C, McCall A, Nedelec M, Dawson B, Baquet G, Dupont G (2017). Recovery from exercise-induced muscle damage: cold-water immersion versus whole-body cryotherapy. International Journal of Sports Physiology and Performance. PubMed ↩︎
  4. Wilson LJ, Cockburn E, Paice K, Sinclair S, Faki T, Hills FA, Gondek MB, Wood A, Dimitriou L (2018). Recovery following a marathon: a comparison of cold water immersion, whole body cryotherapy and a placebo control. European Journal of Applied Physiology. PubMed ↩︎
  5. Hohenauer E, Costello JT, Stoop R, Küng UM, Clarys P, Deliens T, Clijsen R (2018). Cold-water or partial-body cryotherapy? Comparison of physiological responses and recovery following muscle damage. Scandinavian Journal of Medicine & Science in Sports. PubMed ↩︎