by Chris McKinley on Wed Jun 17, 2009 12:31 pm
The research isn't exactly exhaustive with regard to that specific practice, however, what is very well-researched, well-documented, and well-understood is the physiology of hypothermia. It is an undeniable risk with such practices, even with short-term exposure, and great care must be taken to both prevent and treat it. I cannot stress strongly enough that, before you engage in that kind of practice, especially without medical supervision present, you should get a complete physical with a liscensed physician, especially including an echocardiogram. That test will show certain dysfunctions and/or abnormalities which can put a person at risk of cardiac infarction when subjected to extreme changes in temperature.
After that, and with a flying color pass from the doc, it's up to you.