Physiological - Increased Norepinephrine Levels
We found several studies which showed a certain effect on the autonomic nervous system after whole body cryotherapy treatment, including lowering the heart rate  and increased levels of norepinephrine .
Two studies noted that the effect of increased norepinephrine was only seen after the first session of treatment , with no further increase seen in consecutive treatments. One of the studies concluded that this suggested physiological habituation to whole body cryotherapy . It is crucial to mention that both studies were conducted over 5 consecutive days of treatment, and in each study, norepinephrine levels remained elevated throughout the observation period compared to baseline.
Two other studies did not mention the treatment parameters (temperature, number of sessions, time between treatment, etc) as a factor in the increase of norepinephrine .
Application – Increased Energy Levels / Athletic Performance
The release of norepinephrine after whole body cryotherapy treatment indicates a possible means to improve athletic readiness and preparation prior to performance or workout. The treatment has also been shown to reduce perceived fatigue which is thought to be attributed to the release of norepinephrine .
Why is that? First, let’s explore what norepinephrine is, also called noradrenaline. Norepinephrine is a hormone released into the bloodstream and a neurotransmitter. It has the effect of increasing heart rate, releasing glucose from energy stores, and increasing the blood flow to skeletal muscle . All of this works together to improve blood and oxygen supply as well as increased energy.
It is well understood and accepted that norepinephrine is directly correlated with energy levels. One study found that caloric energy expenditure during a 24 hour period increased in participants who exhibited increased levels of norepinephrine .
Application - Improved Mood – Anxiety & Depression
Whole body cryotherapy has been shown to improve mood, anxiety, depression, and improve sleep. This could be attributed to the increases in noradrenaline seen following treatment. Low levels of noradrenaline are directly correlated to anxiety, depression, sleep disorders, and focus disorders such as ADHD .
An incredible study of 60 participants showed dramatic reduction in both anxiety and depression. All participants had either anxiety or depressive disorders and were measured according to Hamilton’s anxiety rating scale (HARS) and Hamilton’s depression rating scale (HDRS). 35% of participants who were given whole body cryotherapy treatment saw an improvement of more than 50% in their test scores for HDRS, while 46% saw the same improvement in HARS scores .
Another study found similar results for depression (anxiety was not explored in this one) by significantly improved HDRS scores .
Application – Improved Sleep
Whole body cryotherapy has been reported to improve sleep quality in many users, the mechanism of which is not well understood. This is possibly related to the release of norepinephrine as discussed previously.
There are claims that improved sleep is attributable to the release of melatonin, which in fact has been shown to be induced when norepinephrine levels are increased . However, we were unable to find evidence which directly explored a change in melatonin levels from the use of whole body cryotherapy.
We did find two studies which examined the impact of sleep after the use of whole body cryotherapy.
One study explored sleep through both subjective as well as objective qualities. Participants were surveyed and both perceived pain and subjective sleep quality were significantly improved in the whole body cryotherapy group. Objective sleep quality also significantly improved, indicated by measured movement during sleep as well as heart rate variability .
Another study tested the use of partial body cryotherapy, the term used to describe the treatment from cryo saunas where the participants head sticks out of the top of the chamber. Results were similar in that there were significantly reduced movements during sleep following cryotherapy treatment .
Note: Information contained within this website and in all materials, communications, or presentations by High Tech Healing is for informative purposes only. Cryotherapy machines are neither designed nor advised for treatment or cure of any illness or disease. No cryotherapy chambers have been tested or approved by the FDA. Please consult with your medical professional before beginning any cryotherapy or recovery method.
 Whole-Body Cryotherapy: Potential to Enhance Athlete Preparation for Competition? - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6691163/#B24
 Whole-body cryotherapy in athletes - https://pubmed.ncbi.nlm.nih.gov/20524715/
 Head Exposure to Cold during Whole-Body Cryostimulation: Influence on Thermal Response and Autonomic Modulation - https://pubmed.ncbi.nlm.nih.gov/25915642/
 The use of whole-body cryotherapy: time- and dose-response investigation on circulating blood catecholamines and heart rate variability - https://pubmed.ncbi.nlm.nih.gov/32474683/
 Parasympathetic Activity and Blood Catecholamine Responses Following a Single Partial-Body Cryostimulation and a Whole-Body Cryostimulation - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3749989/
 Urinary Norepinephrine Is a Metabolic Determinant of 24-Hour Energy Expenditure and Sleeping Metabolic Rate in Adult Humans - https://academic.oup.com/jcem/article/105/4/1145/5718326
 Norepinephrine and Mental Health - https://www.news-medical.net/health/Norepinephrine-and-Mental-Health.aspx#:~:text=In%20the%20sympathetic%20nervous%20system%2C%20norepinephrine%20is%20released,of%20norepinephrine%20can%20result%20in%3A%20Low%20energy%20levels
 Norepinephrine Function, Deficiency and How to Increase - https://draxe.com/health/norepinephrine/
 Norepinephrine: What It Is, Function, Deficiency & Side Effects - https://my.clevelandclinic.org/health/articles/22610-norepinephrine-noradrenaline
 Whole-body cryotherapy as adjunct treatment of depressive and anxiety disorders - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2734249/
 Influence of whole body cryotherapy on depressive symptoms - preliminary report - https://pubmed.ncbi.nlm.nih.gov/26983354/
 Good night and good luck: norepinephrine in sleep pharmacology - https://pubmed.ncbi.nlm.nih.gov/19833104/
 3-min whole body cryotherapy/cryostimulation after training in the evening improves sleep quality in physically active men - https://pubmed.ncbi.nlm.nih.gov/30551730/
 Partial-body cryostimulation after training improves sleep quality in professional soccer players - https://pubmed.ncbi.nlm.nih.gov/30876470/