The Navy SEAL Physical Fitness Guide - Uniformed Services ...

" Dehydration." Salt depletion." Illness/Infections." Cessation of physical activity.There is some disagreement as to how long it takes to lose acclimation to heat, butgenerally speaking after 2 weeks of working in a hot environment, it will take 3 to 4 weeksbefore most of the adaptations are lost.Heat InjuriesThere are many categories and subcategories of heat injuries. However, there arethree classes of heat-induced injuries that will be considered here:" Heat cramps are painful contractions of muscles (usually in the extremities)following vigorous exercise. They occur most commonly in unacclimatizedpersonnel. No specific cause is known (possibly depletion ofelectrolytes), but such cramps usually resolve when acclimation is complete." Heat exhaustion is a potentially serious injury resulting primarily fromdehydration and electrolyte depletion. The affected individual may feel lightheaded,dizzy, nauseous, fatigued, or develop a headache. If heat exhaustionis suspected, the injured individual should be placed in a cool location if possibleand given replacement fluids by mouth or intravenously." Heat stroke is a life threatening injury in which the affected individualloses the ability to regulate temperature and is overcome by soaring bodycore temperatures (greater than 104° F). Such high temperatures can irreversiblyinjure vital organs and result in death if not rapidly treated. Many factorsmay contribute to heat stoke -- even well hydrated personnel may becomevictims if they ignore the warning signs and symptoms (see the followingTable).Table 11-1. Warning Signs of Heat StrokeSigns to Be Aware ofLight-headednessHeadache188 Training for Specific Environments