Variability in Intake and Dehydration in Young Men during a Simulated Desert Walk

Voluntary dehydration was examined in young unacclimatized men walking under simulated desert conditions. Thirty-three subjects (20-33 yrs) walked on a treadmill for 30 min.h(-1) for 6 h in a hot environment (40 C db/ 26 C wb, 4.02 km.h(-1) windspeed). Cool (15 C) water was provided ad libitum in ca...

Full description

Saved in:
Bibliographic Details
Main Authors: Szlyk, Patricia C, Sils, Ingrid V, Francesconi, Ralph P, Hubbard, Roger W, Matthew, William T
Format: Report
Language:English
Subjects:
ADULTS
AS879
AVAILABILITY
BODY TEMPERATURE
BODY WEIGHT
CONTAINERS
COOLING
DEHYDRATION
DESERTS
DRINKING WATER
ENVIRONMENTS
EXERCISE(PHYSIOLOGY)
HEART RATE
HEAT
HIGH TEMPERATURE
MALES
PE62789A
PLASMAS(PHYSICS)
PROTEINS
RECTUM
RISK
SIMULATION
Stress Physiology
Treadmills
WALKING
WATER
WEIGHT REDUCTION
WOUNDS AND INJURIES
WU129
Online Access:Request full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Voluntary dehydration was examined in young unacclimatized men walking under simulated desert conditions. Thirty-three subjects (20-33 yrs) walked on a treadmill for 30 min.h(-1) for 6 h in a hot environment (40 C db/ 26 C wb, 4.02 km.h(-1) windspeed). Cool (15 C) water was provided ad libitum in canteens. Two subpopulations of individuals were identified: those drinkers (D) (n=20) who maintained body weight loss at less than 2% and those who were reluctant to drink (reluctant drinkers, RD) (n=13) and lost more than 2% body weight (BW) despite continual availability of cool water. RD consumed 31% less water than D and this resulted in a significantly greater BW loss in RD than D. However, the only statistically significant differences in plasma indices of hypohydration were the higher final plasma Na+ and protein levels in RD. Rectal temperature was higher in the RD, whereas final heart rates were unaffected. Our results indicate that about 40% of young adult males may be reluctant to drink, thus will voluntarily dehydrate even when cool water ad libitum during intermittent exercise in the heat. The reduced intake of reluctant drinkers may be critical in predisposing them to increased risk of dehydration and heat injury.