The Science

Learn the science behind cold therapy and how it’s changing the daily life of individuals everywhere.

While cold therapy has been an accepted treatment for acute injuries and post-exercise recovery for over 30 years, new research is showing that cold therapy is safe and effective for chronic diseases and general well-being.

Cold therapy provides systemic anti-inflammatory relief, increases positive immune response, and parasympathetic nervous system stimulation. Cold therapy is being applied to provide non-pharmaceutical support for patients with depression and mood disorders, reduction of daily stress and general well-being, chronic disease support including rheumatoid arthritis and fibromyalgia among others, and disease intervention.

Cold therapy has been shown to reduce depression, anxiety, and stress as well as improving mood and general brain function(Galliera et al., 2013; Hayashi et al., 1997; Jungmann et al., 2018; Kinoshita et al., 2006; Lange et al., 2008; Metzger et al., 2000; Misiak & Kiejna, 2012; Polizzi, 2019; Rymaszewska et al., 2020).   The brain releases norepinephrine during cold stress, which is shown to reduce depression and anxiety. Heart rate and heart rate variability are linked to reductions in stress as well, with reductions in heart rate and heart rate variability occurring with cold therapy. Mood and brain function improve through stimulation of the parasympathetic nervous system.

Physiological effects are likely mediated by stimulation of the Vagus nerve and modulation of hormones(Jungmann et al., 2018; Lange et al., 2008; Metzger et al., 2000; Polizzi, 2019). This includes weight loss by stimulating growth of brown fat and lowering white fat. Brown fat, often referred to as “good” fat, increases energy burning and is responsible for body thermoregulation. In part through stimulation of the Vegas nerve complex, cold therapy reduces inflammatory responses throughout the body and thus stimulates the body to heal as well as increasing positive immune response for fighting disease and infection. This beneficial response may be what reduces symptoms and inflammatory markers present in blood from autoimmune disorders such as rheumatoid arthritis and fibromyalgia.

  • Pain Management

    Cold therapy reduces pain by desensitizing nerves and reducing swelling.

  • Inflammation

    Inflammation occurs at specific sites within the body, for example an injury, or can be systemic. Cold therapy reduces localized inflammation from exercise ... Read More and injuries by reducing edema. Systemic inflammation is usually identified through blood samples and identification of specific hormone markers. Cold therapy reduces systemic inflammation through changes in hormones due to stimulation of the Vagus nerve complex. 

  • Depression and Anxiety

    Cold therapy can help alleviate depression and anxiety. Research indicates that people with depressive symptoms typically have inflammatory markers and cold ... Read More therapy significantly improves both the systemic inflammation and depression and anxiety symptoms. Cold therapy is a non-pharmaceutical supporting therapy.

  • Mood and Brain Function

    Cold therapy activates hormonal responses in healthy people as well those suffering from chronic diseases such as depression, fibromyalgia, and ... Read More rheumatoid arthritis. This reduces whole-body inflammation and has antioxidant effects.

  • Heart Rate Variability

    Heart Rate Variability is an indicator of physical and psychological stress. Cold therapy reduces stress and induces relationation by reducing ... Read More heart rate variability.

  • Vasoconstriction

    Cold therapy initiates vasoconstriction of blood vessels in the skin and extremities, which aids in reducing muscle pain, fatigue, and swelling. Cold therapy ... Read More initiated vasoconstriction may be a preventative measure against dementia including Alzheimer’s Disease.

  • Cold-water immersion

    Full or partial body immersion into water at 15 degrees C. Can be conducted in a clinical or home setting.

  • Whole-body cold therapy

    Generally refers to cold air therapy (-110 degree C or colder) in a special chamber in a clinical setting only.

  • Cryotherapy

    Refers to a variety of delivery methods of cold therapies.

  • Autoimmune disorders such as rheumatoid arthritis and fibromyalgia are inflammatory responses. Cold therapy has been proven to provide non-pharmaceutical relief to symptoms. Whole-body cold therapy provides short-term pain relief allowing for chronic pain management and treatment.

    from Metzger et al., 2000

  • Additional studies by Lange et al also showed that inflammatory markers such as TNF-alpha and IL-1 are significantly reduced with cold therapy, indicating a long-term effect.

    from Lange et al., 2008

  • There is strong evidence of improvement for psychological factors such as depression and mood disorders as well as positive feelings of general well-being with whole-body cold therapy with effects lasting at least two weeks after the final session.

    (Rymaszewska et al., 2020)

  • Intensive physical exertion (exercise) results in fatigue, muscle damage, and edema. Cold water immersion therapy reduces pain, fatigue, and edema for 90-96 hours after treatment.

    Bieuzen et al., 2013; Bleakley et al., 2012

  • Stress in the form of physical exertion (exercise) as well as life stress trigger similar hormonal responses that affect heart rate and heart rate variability. Cold water immersion therapy stimulates the Vagus nerve, which in turn lowers the subject’s heart rate and improves heart rate variability. These reduce stress and induce relaxation.

    Hayashi et al., 1997; Jungmann et al., n.d.; Kinoshita et al., 2006

  • Dementia including Alzheimer’s disease is believed to be an inflammatory response with impairment of the vascular system and oxidative stress on the brain. Similar to the short-term benefits to athletes for vasoconstriction and reduction of inflammation and edema, studies indicate that the brain receives similar benefits. Cold water immersion may be a cost effective preventative measure for development of dementia before symptoms develop.

    Misiak & Kiejna, 2012

  • Jungmann et al provide a comprehensive review of previous studies regarding benefits of stimulating the Vagus nerve, which is a large nerve complex that connects the cranial nerves through the neck to the abdominal organs, in their cold stimulation trial. They found a statistically significant cardiac-vagal nerve activation occurred that resulted in reduced heart rate and improved heart rate variability through non-invasive stimulation of the Vagus nerve in the neck. This finding has application to not only recovery for athletes after exercise but also for people with regular daily stress. Stimulation of the Vagus nerve induces the diving reflex, which is a specific pattern of respiratory, cardiac, and vascular responses, which may be a non-conscious attempt by the body to conserve oxygen.

  • De Oliveira Ottone et al found that cold water immersion accelerates parasympathetic activation of the Vagus nerve, thus speeding recovery, while warm water immersion blunts post exercise parasympathetic activation.

  • Kinoshita et al and Hayashi et al found that only cold water immersion activates the Vagus nerve through parasympathetic activation. There was no change in heart rate variability with warm water immersion.

  • Bleakley et al found there was statistically significant improvement for fatigue and general physical recovery immediately after the cold-water immersion treatment and post-exercise.

  • Galliera et al found a significant increase in at least one remodeling osteoimmunological biomarker after whole body cryotherapy, which indicates the treatment induces bone development.

  • Young and healthy men were found to benefit from at least one treatment of whole-body cryotherapy for reduction of inflammatory response to exercise.

  • Alzheimer’s disease, a common form of dementia, is believed to be caused by changes and impairment of the vascular system, oxidative stress, and inflammatory response within the brain. Whole body cryotherapy (cold-water immersion) provides anti-inflammatory and anti-oxidative effects and therefore may be a cost-effective preventative procedure for Alzheimer’s disease and potentially other forms of dementia.

  • Lange et al provided an alternative method for cold air delivery and tested for inflammatory markers such as TNF-alpha and IL-1. Both markers showed significant reduction at the end of the five day treatment. This indicates that there is systemic inflammatory reduction, which is often indicated with medication only.

  • A number of depressive symptoms (sadness, loss of pleasure, self-criticalness, crying, loss of interest, and indecisiveness) were statistically improved two weeks after the last Whole Body Cryotherapy treatment. Approximately 73% of the treated patients reported feeling “recovered” across their range of symptoms prior to treatment, which compared to 28% of the control group. This indicates the treatment caused the recovered condition as opposed to a placebo effect. Similarly, treated patients had improvement in cognitive-affective dimension and somatic dimension, meaning their mind-body relationship improved including secondary outcomes for quality of life, pain, anxiety, depression, and general mood. Depression has been linked to inflammation markers, specifically TNF-alpha and IL-1. Depressed patients also have oxidative stress markers. In this study, no changes were observed in these markers but the researchers speculate this was due to the antidepressant medication, which can affect liver function. The researchers found that whole-body cryotherapy can be a strong supporting therapy with pharmacological treatment for mental health.

  • Banfi et al conducted a literature review of athlete use of whole body cryotherapy. They found that there is supporting evidence that whole body cryotherapy is effective in helping athletes recover from injuries as well as improving recovery without risk of triggering antidoping rules.

  • Autoimmune disorders such as fibromyalgia and rheumatoid arthritis can cause significant discomfort and pain. The pain can make it difficult for patients to complete physical and occupational therapy. In the study, patients achieved significant pain reduction for approximately 90 minutes from cold air treatment prior to their physical and occupational therapy. The whole body cold therapy permitted for more intensive and complete physical and occupational therapy than without the treatment.

  • This research article provides a literature review of studies conducted by others with a focus on contrast water therapy (alternating between warm and cold water immersion). The study found there were better outcomes using cold-water immersion for muscle damage and that this beneficial effect was present 96 hours after treatment. The authors noted that most contrast water therapy ends with cold-water immersion and the well documented benefits of cold-water immersion, also known as cryotherapy, in reducing edema and analgesic effect on nerves may be the reason there is little statistical difference between cold-immersion therapy and contrast water therapy. In essence, there may be little to no affect for the warm-water immersion and all benefits are the result of the cold-water immersion.

  • This article summarizes the theory and science behind Cold Thermogenesis including benefits. In the most basic sense, the body must work harder to maintain homeostasis and core body temperature. However, there is strong evidence that the hormones involved in body temperature regulation also break down fat and increase key hormones such as epinephrine and norepinephrine, and thyroid regulating hormones. Regulation of these hormones could lead to treatments for obesity and other metabolic disorders. Cold exposure has been linked to increased cognitive capacity, boosts to immunity including reductions in inflammation, improved sleep, and promotion of recovery after exercise.

  • Kwiecien et al advocates for cryotherapy using locally administered phase change material (PCM), for 3-6 hours. The PCM is made of materials that are designed to maintain the desired localized temperature (e.g. 15 degrees C) for extended periods (e.g. 3 hours) while absorbing heat from the target area. The practice is similar to providing direct ice to a target muscle group without managing melt water. However, no systemic affects were noted.

  • This web article provides basic information on when cold versus warm therapy is recommended for acute (short-term) injuries. This can include muscle soreness as well as edema and other inflammation.

  • The following are non-research journal articles that provide summaries and basic information on cold therapy.

References List

  • Banfi, G., Lombardi, G., Colombini, A., & Melegati, G. (2010)

    Whole-body cryotherapy in athletes. In Sports Medicine(Vol. 40, Issue 6, pp. 509–517).

    View source
  • Bellendir, T., & Joseph, T. (2020)

    Ice Packs vs. Warm Compresses For Pain. Health Encyclopedia University of Rochester Medical Center.

    View source
  • Bleakley, C., McDonough, S., Gardner, E., Baxter, G. D., Hopkins, J. T., & Davison, G. W.

    Cold-water immersion (cryotherapy) for preventing and treating muscle soreness after exercise. Cochrane Database of Systematic Reviews, 2.

    View source
  • Polizzi, M. (Biostrap). (2019)

    Cold Thermogenesis: How Low Temperatures Boost Long-Term Health. Biostrap Labs.

    View source
  • Boitel, Guillaume (Doctor of Physiology, Bio-mechanics, and S. S. (2019)

    Recovery: The Benefits of Cold-Water Immersion for Runners. RunningCare.Com.

    View source
  • Choo, L. (2020)

    Neurology of cold thermogenesis — Neuro Athletics. Neuro Athletics.

    View source
  • De Oliveira Ottone, V., De Castro Magalhães, F., De Paula, F., Avelar, N. C. P., Aguiar, P. F., Da Matta Sampaio, P. F., Duarte, T. C., Costa, K. B., Araújo, T. L., Coimbra, C. C., Nakamura, F. Y., Amorim, F. T., & Rocha-Vieira, E. (2014)

    The effect of different water immersion temperatures on post-exercise parasympathetic reactivation. PLoS ONE, 9(12).

    View source
  • Śliwicka, E., Cisoń, T., Straburzyńska-Lupa, A., & Łucja Pilaczyńska-Szcześniak, &. (n.d.)

    Effects of whole-body cryotherapy on 25-hydroxyvitamin D, irisin, myostatin, and interleukin-6 levels in healthy young men of different fitness levels.

    View source
  • Galliera, E., Dogliotti, G., Melegati, G., Corsi Romanelli, M. M., Cabitza, P., & Banfi, G. (2013)

    Bone remodelling biomarkers after whole body cryotherapy (WBC) in elite rugby players. Injury, 44(8), 1117–1121.

    View source
  • Hayashi, N., Ishihara, M., Tanaka, A., Osumi, T., & Yoshida, T. (1997)

    Face immersion increases vagal activity as assessed by heart rate variability. European Journal of Applied Physiology and Occupational Physiology, 76(5), 394–399.

    View source
  • Jungmann, M., Vencatachellum, S., Van Ryckeghem, D., & Vogele, C. (2018)

    Effects of Cold Stimulation on Cardiac-Vagal Activation in Healthy Participants: Randomized Controlled Trial. JMIR Formative Research, 2(2).

    View source
  • Kinoshita, T., Nagata, S., Baba, R., Kohmoto, T., & Iwagaki, S. (2006)

    Cold-Water Face Immersion Per Se Elicits Cardiac Parasympathetic Activity. Circulation Journal, 70(6), 773–776.

    View source
  • Jungmann, M., Lu, M. J., Ryckeghem, D. Van, & Vögele, C. (n.d.)

    Effects of cold stimulation on cardiac-vagal activation: Randomized controlled trial with healthy participants.

    View source
  • Rymaszewska, J., Lion, K. M., Pawlik-Sobecka, L., Pawłowski, T., Szczes´niak, D., Szczes´niak, S., Bieta Trypka, E. ˙, Rymaszewska, J. E., Zabłocka, A., Stanczykiewicz, B., Morgado, P., Stanek, A., & Dell’osso, L. (2020)

    Efficacy of the Whole-Body Cryotherapy as Add-on Therapy to Pharmacological Treatment of Depression—A Randomized Controlled Trial. Article, 11, 1.

    View source
  • Banfi, G., Lombardi, G., Colombini, A., & Melegati, G. (2010)

    Whole-body cryotherapy in athletes. In Sports Medicine(Vol. 40, Issue 6, pp. 509–517).

    View source
  • Bellendir, T., & Joseph, T. (2020)

    Ice Packs vs. Warm Compresses For Pain. Health Encyclopedia University of Rochester Medical Center.

    View source
  • Kwiecien, S. Y., McHugh, M. P., & Howatson, G. (2020)

    Don’t Lose Your Cool With Cryotherapy: The Application of Phase Change Material for Prolonged Cooling in Athletic Recovery and Beyond. Frontiers in Sports and Active Living, 2.

    View source
  • Schmitz, A. (n.d.)

    8 Ice Bath Dos and Don’ts | ACTIVE. Active.Com. Retrieved April 11, 2021.

    View source
  • Metzger, D., Zwingmann, C., Protz, W., & Jackel, W. H. (2000)

    Die bedeutung der ganzkorperkaltetherapie im rahmen der rehabilitation bei patienten mit rheumatischen erkrankungen – Ergebnisse einer pilotstudie. Rehabilitation,39(2), 93–100.

    View source
  • Misiak, B., & Kiejna, A. (2012)

    Translating whole-body cryotherapy into geriatric psychiatry – A proposed strategy for the prevention of Alzheimer’s disease. Medical Hypotheses, 79(1), 56–58.

    View source
  • Lange, U., Uhlemann, C., & Müller-Ladner, U. (2008)

    Serielle ganzkörperkältetherapie im criostream bei entzündlich-rheumatischen erkrankungen. Eine pilotstudie. Medizinische Klinik, 103(6), 383–388.

    View source