Shivering Capacity and Prediction of Survival Time
Abstract
The accuracy of prediction models of survival time for cold exposure depends heavily on the estimation of shivering capacity which is poorly understood. The purpose of this study was to measure shivering endurance which was hypothesized to diminish through pre-exposure exercise. Thirteen healthy and fit males participated in an experiment designed to test their shivering response following 5 h of high intensity mixed exercise during which only water was consumed. Following exercise for the fatigue trial or beginning in a fresh state for the control trial, and instrumentation for physiological monitoring (rectal and skin temperatures, metabolic rate, heat loss, heart rate, EMG), subjects assumed a seated position in a 10 deg C air environment wearing shorts, t-shirt, rainhat, and neoprene boots and gloves. After 30 min, the subjects were showered continuously with cold water on their backs accompanied by a 6 per km per h wind for up to 4 h. Three subjects lasted the complete duration for both trials. While shivering fatigue was not observed, there were vast differences in the shivering response of the subjects which, in addition to body fatness, influenced duration. The results also indicate an over-reliance on glycogen stores for shivering in the present prediction model based on the subject's utilization of fat during shivering in the fatigue trial.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1998
- Accession Number
- ADA353706
Entities
People
- Peter Tikuisis
Organizations
- Defence Research and Development Canada