Thermoregulatory Responses to Intermittent Exercise Are Influenced by Knit Structure of Underwear
Abstract
The purpose of this study was to evaluate the role of knit structure in underwear on thermoregulatory responses. Underwear manufactured from 100% polypropylene fibers in five different knit structures (1-by-1 rib, fleece, fishnet, interlock, double-layer rib) were evaluated. All five year underwear prototypes were tested as part of a prototype clothing system. Measured on a thermal manikin these clothing systems had total thermal resistances, I(tot), of 0.243, 0.268, 0.256. 0.248 and 0.250 square meter/k/w, respectively. Human testing was done on eight male subjects and took place at T(a) = 5 C, t(sp) = 3. 5 c and V(a) = 0.32 m/s. The test comprised a repeated bout of 40 min cycle exercise (315 w/square meter; 52 + or - 4.9% maximum oxygen consumption followed by 20 min of rest (w/sqi M). VO2, heart rate, esophageal temperature, local skin temperatures, ambient air temperature, dew point temperature at three skin sites and in the ambient air were monitored. Onset of sweating was evaluated from the dew point sensor recordings. The differences in knit structure of the underwater in the clothing systems resulted in significant differences in mean skin temperature, local and average skin wetness, non-evaporated and evaporated sweat during the course of the core temperature.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1989
- Accession Number
- ADA209087
Entities
People
- Ruth Nielsen
- Thomas L. Endrusick
Organizations
- United States Army Research Institute of Environmental Medicine