Keeping older individuals cool in hot and moderately humid conditions: wetted clothing with and without an electric fan
Abstract
The present study evaluated whether wearing a water-soaked t-shirt, with or without electric fan use, mitigates thermal and cardiovascular strain in older individuals exposed to hot and moderately humid conditions. Nine healthy older individuals (68 ± 4 yr; five women) completed three 120-min heat exposures (42.4 ± 0.2°C, 34.2 ± 0.9% relative humidity) on separate days while wearing a dry t-shirt (CON), a t-shirt soaked with 500 ml of tap water (WET), or a t-shirt soaked with 500 ml of tap water while facing an electric fan (2.4 ± 0.4 m/s; WET+FAN). Measurements included core and skin temperatures, evaporative mass losses, heart rate, and blood pressure. In the WET condition, elevations in core temperature were attenuated compared with DRY from 30 to 120 min and compared with WET+FAN from 30 to 90 min ( P < 0.05). Evaporative mass losses (inclusive of sweat and water losses from the shirt) were greatest in WET+FAN, followed by WET, and then DRY ( P < 0.01). Sweat losses were lowest in WET, followed by DRY, and then WET+FAN ( P < 0.01). Heart rate was lower only at 60 min in WET versus DRY ( P = 0.01). No differences in mean arterial pressure were observed ( P = 0.51). In conclusion, wearing a water-soaked t-shirt without, but not with, electric fan use is an effective heat management strategy to mitigate thermal strain and lower sweat losses in older individuals exposed to hot and moderately humid conditions.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Mar 01, 2020
- Source ID
- 10.1152/japplphysiol.00786.2019
Entities
People
- Craig G Crandall
- Gilbert Moralez
- Matthew N Cramer
- Mu Huang
Organizations
- National Institutes of Health
- Natural Sciences and Engineering Research Council
- United States Department of Defense
- University of Texas Southwestern Medical Center
- University of Texas at Austin