Problems of body heat loss in water immersion.

Cognitive Performance Is Enhanced during Cold-water Immersion and Exercise

for normally hydrated individuals. However, when working in stressful environments for extended durations, particularly when wearing personal protective equipment, fluid losses via sweat secretion are dramatically elevated, and can approach 8-16 L.day -1 . Indeed, during a moderate exercise-heat stress, whole-body sweat rates typically range between 1-1.5 L.h -1 , and fluid loss at this rate si...

Thermal effects of dorsal head immersion in cold water on nonshivering humans.

Personal floatation devices maintain either a semirecumbent flotation posture with the head and upper chest out of the water or a horizontal flotation posture with the dorsal head and whole body immersed. The contribution of dorsal head and upper chest immersion to core cooling in cold water was isolated when the confounding effect of shivering heat production was inhibited with meperidine (Dem...

HIGHLIGHTED TOPIC A Physiological Systems Approach to Human and Mammalian Thermoregulation Thermal effects of whole head submersion in cold water on nonshivering humans

Pretorius, Thea, Gerald K. Bristow, Alan M. Steinman, and Gordon G. Giesbrecht. Thermal effects of whole head submersion in cold water on nonshivering humans. J Appl Physiol 101: 669–675, 2006. First published April 13, 2006; doi:10.1152/japplphysiol.01241.2005.— This study isolated the effect of whole head submersion in cold water, on surface heat loss and body core cooling, when the confoundi...

Current concepts and practices applicable to the control of body heat loss in aircrew subjected to water immersion.

Heat balance precedes stabilization of body temperatures during cold water immersion.

Certain previous studies suggest, as hypothesized herein, that heat balance (i.e., when heat loss is matched by heat production) is attained before stabilization of body temperatures during cold exposure. This phenomenon is explained through a theoretical analysis of heat distribution in the body applied to an experiment involving cold water immersion. Six healthy and fit men (mean +/- SD of ag...