Accession Number : ADA139284

Title :   Influence of Hydration Level and Body Fluids on Exercise Performance in the Heat,

Corporate Author : ARMY RESEARCH INST OF ENVIRONMENTAL MEDICINE NATICK MA

Personal Author(s) : Sawka,M N ; Francesconi,R P ; Young,A J ; Pandolf,K B

PDF Url : ADA139284

Report Date : Jan 1984

Pagination or Media Count : 31

Abstract : During exercise in the heat, sweat output often exceeds water intake resulting in hypohydration which is defined as a body fluid deficit. This fluid deficit is comprised of water loss from both the intracellular and extracellular fluid compartments. Hypohydration during exercise causes a greater heat storage and reduces endurance in comparison to euhydration levels. The greater heat storage is attributed to a decreased sweating rate as well as a decreased cutaneous blood flow. These response decrements have been related to both plasma hyperosmolality and a plasma hypovolemia. Subject gender, acclimation state and aerobic fitness do not alter the hypohydration response. Hyperhydration, or body fluid excess, does not appear to provide a clear advantage during exercise-heat stress, but may delay the development of hypohydration.

Descriptors :   *Exercise(Physiology), *Hydration, *Heat stress(Physiology), *Body fluids, Heat, Perspiration, Rates, Output, Requirements, Drinking water, Temperature control

Subject Categories : Stress Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE