Cryotherapy involves exposing the body to extremely cold temperatures, often between -110°C and -140°C, typically using chilled air or nitrogen vapor for short durations. The primary concern for first-time users is whether this intense cold is painful. Generally, the sensation is characterized by profound, temporary discomfort rather than pain indicating injury. This brief, intense exposure triggers a systemic response, which users often describe as shocking or highly invigorating.
The Sensation of Intense Cold
The experience inside a whole-body cryotherapy chamber is a rapid progression of sensations over the typical two to four-minute session. As the chilled air envelops the skin, the feeling is one of immediate, intense dry cold, unlike the damp chill of an ice bath. Within the first minute, the skin temperature drops rapidly, stimulating cold receptors all over the body.
This initial shock quickly transitions into a localized stinging or prickly sensation, particularly noticeable on the extremities like the fingers and toes. The feeling is often likened to intense “pins and needles” as the body reacts to the sudden temperature drop. The discomfort peaks shortly before the session ends.
As the session nears its conclusion, the extreme cold begins to induce a numbing effect, which is a form of temporary, localized analgesia. This numbness helps manage the discomfort and is part of the therapy’s intended effect of reducing pain perception. The experience is a test of mental fortitude against a temporary cold stimulus.
How the Body Reacts to Extreme Temperatures
Intense cold exposure initiates a rapid, involuntary physiological defense mechanism known as the “fight-or-flight” response. This immediate stress reaction is mediated by the sympathetic nervous system, which works to protect the body’s core temperature. A primary action is rapid peripheral vasoconstriction, where blood vessels near the skin’s surface narrow significantly.
This narrowing of blood vessels redirects blood flow from the limbs and skin toward the vital internal organs. This survival mechanism helps maintain the core temperature and is the physical cause of the intense cold sensation on the skin. Simultaneously, the extreme cold slows the speed at which nerve impulses are conducted.
This slowing of nerve signals raises the pain threshold in the exposed areas, contributing to the numbing effect felt toward the end of the session. The body also releases hormones, including norepinephrine and endorphins, which contribute to the feeling of alertness and improved mood reported after the session.
Differences Between Whole-Body and Localized Treatments
The sensation of cold varies significantly depending on whether the treatment is whole-body or localized. Whole-Body Cryotherapy (WBC) involves systemic exposure to temperatures between -110°C and -140°C for a short duration, usually two to three minutes. This method creates uniform, intense skin cooling across the entire body, leading to widespread discomfort.
Localized cryotherapy, conversely, involves using a handheld device to direct a concentrated stream of chilled air onto a specific area, such as a sore joint or muscle. Although temperatures can sometimes be even colder at the point of application, the treatment is targeted and lasts longer, often five to ten minutes.
The sensation during localized treatment is a deeper, more pronounced burning or aching cold specifically at the application site, which can be more uncomfortable than the systemic chill of WBC. Since the rest of the body is not exposed, the treatment lacks the full-body systemic shock. Localized application is primarily used for targeted inflammation reduction, while WBC is sought for overall recovery and systemic anti-inflammatory effects.