a. Body Heat and Physical Work. The body is continually producing heat, but
during physical work the production of heat is increased in proportion to the type,
intensity, and duration of the work. Thus, physical work accentuates the effects of high
b. Body Heat and Physical Condition. Individual susceptibility to heat stress
may be increased by a variety of conditions including:
Acute and chronic infections.
Reactions to immunizations.
Conditions affecting sweat secretion.
Heat rash or acute sunburn.
Use of alcohol.
Lack of sleep.
The risk of heat injury is much higher in overweight persons than in those of
normal weight. Special care should be exercised when such persons are
exposed to high temperatures.
4-10. TYPES OF HEAT INJURY
Although humans live in various regions with marked variations in the environmental
heat, the temperature of the human body is regulated within extremely narrow limits.
a. Three Types. Three distinct types of heat injury may occur when the body
cannot deal adequately with the heat. The type of heat injury incurred depends upon
the manner of breakdown of the individual's heat adjustment. These injuries are heat
b. Recognition/Knowledge of First Aid--A Responsibility of All Military
Personnel. The three conditions that produce distinctive signs and symptoms should
be recognized at once--not only by AMEDD personnel, but also by unit personnel--if the
casualty is to receive proper care and attention. All military personnel in the field should
be familiar with the first aid treatment of these conditions.
4-11. HEAT CRAMPS
Heat cramps are primarily caused by the loss of salt in the form of perspiration. Usually,
heat cramps are promptly relieved by rest and by replacing some of the salt and water
lost through perspiration.