You’ve watched it in a new series. You’ve seen it all over social media. You may have read about it in a book, another blog post, an online article or even watched a funny video about it. And if you’ve come to PLUNJ, you’ve done it before! So what is the hype surrounding deliberate cold water exposure?
You may have experienced the numerous health benefits of cold plunging AND sauna bathing. In this post, we’re going to dive into the effects of deliberate cold water immersion on cardiovascular health.
When you submerge your body in icy water, you are physiologically challenging your organ systems. The body has to adjust and regulate heat production and heat loss mechanisms – all to maintain the temperature in the brain and core organs. When the body is not acclimated to extreme cold conditions, blood pressure increases and cold shock may occur.
Vasoconstriction and vasodilation: Warm blood from the core distributes heat to the dermis of the skin (where blood vessels, connective tissue, nerves, oil and sweat glands, and hair follicles live), and then the outer layer of the skin.
Shivering thermogenesis: Shivering helps the body generate extra heat by increasing muscle activity, which elevates the metabolic rate. Metabolic heat production, otherwise known as cell respiration, is the main generator of additional heat production in the cold. But when the body shivers, heat production is about 5 times greater than the basal metabolic heat production alone.
Non-shivering thermogenesis: Nonshivering thermogenesis is a metabolic process located primarily in brown adipose tissue (BAT or brown fat, the good fat) and controlled by activity of the sympathetic nervous supply of brown fat. When exposed to the cold, blood flow to brown fat increases and the body generates heat. Mitochondria in brown fat burn triglycerides (a type of lipid) and sugar from the bloodstream to produce that heat. Brown fat can grow if it is regularly stimulated by the cold – meaning, cold exposure can help you develop brown fat!
Benefits from Regular Cold Water Immersion
One study tested a group of cold-adapted individuals (specifically winter swimmers) and a group of individuals who were not adapted to the cold. The cold-adapted subjects showed an improvement in cardiovascular risk factor markers not seen in the other group tested.
For five weeks in another study, a group of healthy men were put through a cold acclimation program. Their blood pressure increased substantially during the first cold water immersion. But after the cold acclimation program, their blood pressure remained at normal levels during immersion which indicates an ability in the body to develop cold tolerance.
Other studies show that cold water immersion might reduce white fat or transform it to brown fat, as well as minimize insulin resistance or increase insulin sensitivity. By adding cold water plunges to our wellness regimens, (some research suggests spending a total of eleven minutes per week in an ice bath) we may be able to improve our cardiovascular health and protect ourselves from obesity and other metabolic diseases.
A Word of Caution
It is important to note that ice-cold water immersion may be harmful to those with hazardous cardiac arrhythmias and other cardiovascular disease symptoms. If you are suffering from negative cardiovascular risk factors, consult your doctor before using a cold plunge.
Conclusion
Most of us see the importance and appeal of keeping our bodies healthy, and wellness and longevity is becoming more and more of a priority. Deliberately and intentionally exposing yourself to cold water up to the neck may improve your cardiovascular health. And if you’re nervous, remember that you can challenge your mental toughness as well as develop your cold tolerance.
Conquer the cold by getting cold!
Sources:
Didrik Espeland, Louis de Weerd, & James B. Mercer. (2022). Health effects of voluntary exposure to cold water – a continuing subject of debate. International Journal of Circumpolar Health, 81(1). https://doi-org.ezproxy.uvu.edu/10.1080/22423982.2022.2111789
Gordon, K., Blondin, D. P., Friesen, B. J., Tingelstad, H. C., Kenny, G. P., & Haman, F. (2019). Seven days of cold acclimation substantially reduces shivering intensity and increases nonshivering thermogenesis in adult humans. Journal of applied physiology (Bethesda, Md. : 1985), 126(6), 1598–1606. https://doi.org/10.1152/japplphysiol.01133.2018
Himms-Hagen J. (1984). Nonshivering thermogenesis. Brain research bulletin, 12(2), 151–160. https://doi.org/10.1016/0361-9230(84)90183-7