Immersion cooling during hyperthermia: why warmer may be better

A significant number of military personnel suffer from exertional heat illness, with some extreme cases resulting in death. These illnesses may occur without warning, they are often characterised by a rapid onset and can occur even in experienced personnel. Various field treatments for hyperthermia have been developed, and one of particular interest is the use of cold-water immersion. Not surprisingly, immersion in ice-cold water (0-2oC) has been shown to be an effective means of rapidly reducing body core temperature (Proulx et al., 2003, 2006).