Cold Therapy - Methods compared
Cryotherapy vs cold-water immersion
Last updated 29 September 2026. How we write this .
A cryotherapy chamber is far colder than an ice bath, but air draws heat out slowly, so muscles cool by about the same amount. Cold water has more evidence for easing soreness. Neither beats a placebo.
Start here A cryotherapy chamber is far colder than an ice bath, but air draws heat out slowly, so muscles cool by about the same amount. Cold water has more evidence for easing soreness. Neither beats a placebo.
By the end, you will understand What is the difference between cryotherapy and an ice bath? Which cools your body more? Does a cryotherapy chamber help recovery more than an ice bath? Key words used in this lesson Placebo An inactive comparison given so that the effect of expectation can be separated from the effect of the intervention itself. Without one, improvement over time cannot be attributed to the treatment. Meta-analysis A statistical method for combining the results of multiple studies into a single estimate. More reliable than any one study, but bounded by the quality of what went into it. Full plain-English glossary
Where this information comes from Claim-cited evidence. Central research claims on this lesson are linked to specific studies or official guidance.
This lesson links the specific studies and guidance used for its central claims.
Our standard: expert or athlete opinion may illustrate a viewpoint, but it is never treated as proof. Read the editorial policy .
Report an error or outdated claim .
A cryotherapy chamber chills your skin harder than an ice bath, but the muscle underneath ends up about the same temperature. Cold-water immersion has the larger body of evidence for easing soreness after exercise. Chambers have very little, and in the head-to-head trials that exist, neither did better than a placebo at speeding recovery.
The two also carry different risks. Water brings cold shock and, outdoors, drowning. Chambers bring extreme cold air and, in some designs, liquid nitrogen.
What is the difference between cryotherapy and an ice bath?
Whole-body cryotherapy means standing in a room-sized chamber filled with refrigerated, breathable air, cooled to between minus 50 and minus 150°C, for a few minutes, with your head inside. A 2023 safety review from an international group of cryotherapy researchers, led by Fabien Legrand, stresses that this is different from partial-body cryotherapy. That uses a can-shaped cabin, often called a cryosauna, which leaves your head outside and is filled with a mist of liquid nitrogen at about minus 190°C. The review says the two are often confused, including in reports about safety.
An ice bath, or cold-water immersion, means sitting in cold water up to the waist, chest or neck. In the study described below, the water was 8°C. That sounds mild next to minus 110°C. It is not, because of what water does to heat.
Which cools your body more?
The clearest test comes from a 2012 study at the University of Limerick led by Joseph Costello. Twenty active men had both treatments, a week or more apart: a few minutes in a minus 110°C chamber and the same time in 8°C water. Probes measured skin temperature, temperature inside the thigh muscle and core temperature for an hour afterwards.
The chamber won on the skin. Average thigh skin temperature fell by 12.1°C after the chamber, against 8.4°C after the water. Deeper down, the difference disappeared. At 1 cm into the muscle, temperature fell by 1.6°C after the chamber and 2.0°C after the water. Core temperature fell by 0.3°C and 0.4°C. The authors concluded that the huge temperature gap, about 118°C colder in the chamber, simply made up for air being a much poorer conductor of heat than water.
Water also does something air cannot. It presses on your body. A 2006 review by Wilcock and colleagues at Auckland University of Technology explains that this pressure, called hydrostatic pressure, moves fluid from the tissues back into the blood vessels, may reduce swelling in muscles, and increases the amount of blood the heart pumps. So an ice bath is really two treatments at once, cold and pressure. A chamber is cold alone.
Does a cryotherapy chamber help recovery more than an ice bath?
There is no good evidence that it does. A 2015 Cochrane review, also led by Costello, looked for trials of whole-body cryotherapy for muscle soreness after exercise. It found four small trials with 64 people, all but four of them men. The evidence was rated very low quality, and the reviewers concluded there was not enough to say whether chambers reduce soreness or improve how recovered people feel. None of the trials compared chambers with cold water, and none actively monitored for side effects.
Cold water has more behind it. A 2015 meta-analysis by Erich Hohenauer and colleagues pooled 36 studies of different cooling methods after hard exercise. Cooling reduced soreness at 24, 48 and 96 hours compared with doing nothing, and the effect came mainly from cold-water immersion. Only two of the 36 studies used extreme cold air. Across the whole set, cooling made no measurable difference to objective markers of recovery, such as substances in the blood that signal muscle damage.
The most useful studies are the ones that test both methods against a placebo. Laura Wilson's team at Middlesex University in London ran two. In the first, published in 2018, 31 endurance-trained men ran a marathon and were then randomly assigned to cold water, a cryotherapy chamber or a placebo. Muscle function recovered worse after the chamber than after cold water, and neither cold treatment beat the placebo for functional recovery. In the second, published in 2019, 24 strength-trained men did a hard leg workout. This time the chamber reduced soreness at 24 hours and helped peak force at 48 hours compared with cold water and the placebo, but most other measures were trivial, unclear or favoured the placebo. The authors concluded that neither cold treatment sped recovery more than the placebo.
So the two head-to-head trials disagree about which cold is better, but agree that belief in the treatment may be doing much of the work.
Is a cryotherapy chamber safer than cold water?
It is safe in different ways, not safer overall. With no water, there is no drowning risk and no gasping breath taken underwater. Cold water's main dangers, cold shock and a sudden jump in heart rate and blood pressure, are covered in Cold shock, blood pressure and who should be careful.
Chambers have their own record. Legrand's review found seven published reports describing 16 adverse events. Most were minor, such as headache, dizziness and long-lasting shivering, and most people recovered within a month. A few were serious, including bleeding in the brain and, in a 56-year-old man in Mexico with high blood pressure, a tear in the wall of the aorta, the body's main artery, a week after treatment. The review says partial-body cabins carry an inherently high risk of cold burns and of oxygen shortage, because nitrogen gas is injected directly into them. It cites the case of a 71-year-old man whose back was burned by liquid nitrogen in one.
Keep in mind who wrote that review. Its authors work on cryotherapy and argue that health agencies, including the US Food and Drug Administration, have overstated the risks by mixing up the two types of machine. Even so, the Cochrane reviewers found that none of the trials they examined monitored side effects properly, so nobody yet knows how common problems are.
What is still unknown?
Nearly all this research involves small groups of young, fit men. The Cochrane review found no trials at all in women or elite athletes. Nobody can be blinded to standing in minus 110°C air or sitting in cold water, and machines vary so much that a result from one chamber may not apply to another. For people with heart disease, high blood pressure, poor circulation or Raynaud's, the evidence on either method is thinner still, which is a reason to talk to a GP first.
This lesson is general education comparing two cold treatments, not medical advice. If you have a heart, blood pressure or circulation condition, or feel unwell during or after cold exposure, seek medical help and call 999 in an emergency.
Related in this classroom The studies behind this page Muscle, skin and core temperature after -110°C cold air and 8°C water treatment - PLoS One, 2012Physiological response to water immersion: a method for sport recovery? - Sports Medicine, 2006Whole-body cryotherapy (extreme cold air exposure) for preventing and treating muscle soreness after exercise in adults - Cochrane Database of Systematic Reviews, 2015The Effect of Post-Exercise Cryotherapy on Recovery Characteristics: A Systematic Review and Meta-Analysis - PLoS One, 2015Recovery following a marathon: a comparison of cold water immersion, whole body cryotherapy and a placebo control - European Journal of Applied Physiology, 2018Whole body cryotherapy, cold water immersion, or a placebo following resistance exercise: a case of mind over matter? - European Journal of Applied Physiology, 2019Evaluating safety risks of whole-body cryotherapy/cryostimulation (WBC): a scoping review from an international consortium - European Journal of Medical Research, 2023Sources for this classroom
Educational content only. Not medical advice, diagnosis or treatment. Always consult a qualified healthcare professional before changing your health regimen.