Benefiting from cryostimulation sessions, i.e. exposure for a few minutes to -90°C, would improve the quality of sleep, according to a new study.
- A cryostimulation session consisted of five minutes of cold exposure in a room cooled to -90°C.
- Volunteers who did it for 5 consecutive days showed an improvement in their sleep and mood.
- Women had greater benefits than men.
After major efforts or competitions, many professional athletes now rely on cryostimulation. But this method, which consists of exposing the body to intense cold for 2 to 4 minutes, would not only be good for accelerating muscle recovery and reducing pain, according to the University of Montreal.
Work carried out by Olivier Dupuy, specialist in physical activity sciences, ensures that daily whole-body cryostimulation sessions would improve the quality of sleep – and affect the mood – of young adults.
Cryostimulation and sleep: more benefits for women
To evaluate the effects of intense cold therapy, researchers brought together 20 healthy people (9 women and 11 men) with an average age of 23 years. These volunteers had to participate in a daily cryostimulation session for five consecutive days. They were then exposed to a temperature of -90°C for five minutes. “All wore underwear or a swimsuit, socks, Crocs-type shoes, mittens and a hat to protect their extremities from the intense cold”specifies the researcher in a press release.
After the session, the volunteers could go about their usual activities. The only instruction given was to avoid drinking alcohol or exercising until bedtime. When they went to bed, they had to wear a headband equipped with brain activity sensors, a wrist activity meter and a heart rate monitor. These three devices measured different physiological data during the night. Participants also had to complete questionnaires every morning on the perceived quality of their sleep. To isolate the effect of cryostimulation, the team also monitored five consecutive nights where there was no organized cold therapy.
The results of the study, published in the journal Cryobiologyshow that a single cryostimulation session is not enough to improve sleep. You need 5 in a row. At that time, the scientists noticed a significant increase in the duration of slow-wave sleep on nights following exposure to intense cold, compared to nights without sessions. “Slow wave sleep, considered the most restorative phase of sleep, increased by an average of 7.3 minutes during the first two sleep cycles”specify the authors.
Another observation: women benefit more from negative temperatures, according to measures of perceived sleep quality. They are felt from 3 to 4 nights. “On a scale of 1 to 5, their score went from 3.4 without cryostimulation on average to 3.9 with cryostimulation. Their perceived level of anxiety, assessed on another scale, decreased from 43 to 38 points.”
Intense cold: a solution to boost health?
Although these improvements may seem modest, they remain very interesting for Olivier Dupuy. “Since our study involves people who sleep well in general, we believe that cryostimulation could be even more beneficial for people who have sleep problems“, says the expert.
“For high-performance athletes it could improve recovery, while for the general population cryostimulation could help people who suffer from chronic inflammation, or even those with mild dementia, in combination with exercise.”he notes.
According to him, this therapeutic approach is likely to find its place in the clinical arsenal against sleep disorders and other health concerns. He also specifies that cryostimulation sessions are already reimbursed by Social Security in certain countries, such as Poland.
