You may have heard that taking a plunge in cold water is linked with reduced stress and improved sleep (via Harper’s Bazaar), so it’s not entirely surprising that there are other ways to activate your parasympathetic nervous system. Placing an ice pack on your chest or neck might also do the trick, according to Sleep.com. This can be particularly beneficial on days when you don’t feel like plunging your entire face into cold water before bedtime. It can also be useful if you’re stressed before you head to bed. A California-based physical therapist told Everyday Health, “If your body is under a lot of stress — even if you don’t realize it — it causes your sympathetic system to be in overdrive.” The sympathetic system is what’s connected to your body’s “flight or fight” response.
Taking an ice water bath could also help, particularly if you’ve been out exercising and feel all hot and sweaty, shared sports medicine physician in the Department of Orthopedic Surgery at the Cleveland Clinic, Dr. Dominic King (via TODAY). “Some people note that it helps them actually sleep better, so after getting really hot, really sweaty, and doing (an ice bath) they just feel rested.”
A 2020 study also found a link between sleep quality in persons with insomnia and vagus nerve stimulation. The results indicate an increase in the production of melatonin, the hormone that regulates your circadian rhythms and sleep (via Psychology Today). Since the evidence seems promising, should you be turning to ice tricks when you can’t get to bed?