Ice baths have become popular and are considered very effective. Many believe they help to recover, lose weight, strengthen physical and mental health, and improve blood flow and libido. The beginning of this fashion was laid by athletes such as runner Paula Radcliffe, and swimmer Michael Phelps, later celebrities and entrepreneurs intercepted the fashion, for example, Twitter cofounder Jack Dorsey. Tempering popularizers such as Hof, who set a Guinness World Record for swimming under ice, maintain interest, saying that a “cold shower a day keeps the doctor away” is the best medicine. Is it so?
Science has refuted all these misconceptions and has not confirmed the expected effects of ice bathing. Moreover, it turned out that ice baths do not speed up recovery. Instead, they noticeably worsen muscle growth after training, reducing the rate of muscle growth by 25%! No positive effect of baths on anxiety reduction was found. And ice baths help only mice to lose weight, not people.
The advantages are illusory, but the threats are real. And the main risk is the heart. The fact is that the cold causes the release of adrenaline, which accelerates the pulse. And diving activates the diver’s reflex, which slows down the pulse. Both oppositely directed processes create a load on the heart, which increases pressure, and can cause arrhythmia up to a cardiac arrest. Studies show that the troponin level, a marker of heart muscle damage, is increased in the blood of people who take ice baths.
Why are they popular? Ice baths are hot on social media. Our human tendency to confuse emotions with efficiency is to blame for everything. Baths stimulate the release of adrenaline and endorphin, which invigorates us. We tend to extremities; it seems to us that the more extreme, the more useful it is. Alas, this is different. In health, the “golden mean” principle is most often true. The media popularize ice baths this way — they make great photos for Instagram. You can feel like a hero just lying in the bathroom! But narcissism kills and humbleness cures!)
So isn’t the cold exposure not working? It can help, but moderation is needed. Instead of ice baths, you can take air baths, as Benjamin Franklin did. The main thing is not to walk naked too close to an open window. A cold shower and sleeping in a cool bedroom are also helpful. For example, just 30 seconds of a cold shower reduces the risk of a cold by 29% (rather than lying in an ice bath for a long time).
Scientists have proven that it is quite enough to sleep in a cool bedroom and this increases your amount of useful brown fat (which burns fat), improves insulin sensitivity, and helps burn calories. Even coolness at 19C is quite effective in increasing the activity of brown fat by 30–40%, as shown by a study by Dr. Paul Lee from Sydney’s Garvan Institute of Medical Research (The Impact of Chronic Cold Exposure in Humans (ICEMAN)). It may not give you a good picture for Instagram, but it is much more useful, safer, and better for your health and ecology. Don’t dress too warmly outside — it’s ideal when it’s cool for you to stand, but it’s warm to walk.
https://physoc.onlinelibrary.wiley.com/doi/10.1113/JP278996
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0139028
https://pubmed.ncbi.nlm.nih.gov/31184819/
https://pubmed.ncbi.nlm.nih.gov/27631616/
https://www.tandfonline.com/doi/full/10.1080/22423982.2022.2111789