However, there are now small retrospective case studies that have been looked at in humans, with some pre-clinical work now under way. (KetoDietApp.com)
This is only one case report, and, caution the authors: «Due to the nature of retrospective case reports, it is unclear, without further evidence, whether the exposure to forced cold water swimming is causally and specifically related to pain remission.» (sciencedaily.com)