Accession Number : ADA138969

Title :   Metabolic, Thermal and Cardiovascular Adjustments to Cold Exposure with Special Reference to Physical Work and Body Composition.

Descriptive Note : Final rept. 30 Sep 80-28 Feb 82,


Personal Author(s) : Magel,J R ; McArdle,W D

PDF Url : ADA138969

Report Date : Jun 1982

Pagination or Media Count : 110

Abstract : Oxygen consumption and rectal temperature (T sub re) were studied in 10 men and 8 women during 1 hr rest and exercise at 36W (8.2 kcal/min) in air and water at 20, 24, and 28 C. At rest, in all water conditions, the obese men ( 22% fat) maintained T sub re at levels similar to control values in air. During work, T sub re increased about 0.4 C under all conditions with essentially no difference in air and the three water temperatures. For average (15-18%) and ( 12%) men, T sub re decreased after 10-30 min rest at all water temperatures with the largest drop in T sub re (-1.4 C; 35.8 C) and increase in oxygen consumption (760 ml) observed for lean men in colder water. Exercise prevented the drop in T sub re in 24 and 28 C water for average men and 28 C water for lean men. For both groups, oxygen consumption was rapidly and significantly elevated when T sub re was reduced, with increases in oxygen inversely related to the fall in T sub re. Although the women possessed nearly twice the % fat as their lean and normal male counterparts, their fall in T sub re at rest was similar to the men at all water temperatures. Viewed somewhat differently, a female of 22% fat does not regulate T sub re when exposed to cold stress at rest as effectively as a male of similar percent fat. This difference in temperature regulation at rest may be partly explained by differences in thermogenesis between men and women in response to cold stress.

Descriptors :   *Stress(Physiology), *Exposure(Physiology), Cardiovascular system, Metabolism, Low temperature, Work, Oxygen consumption, Heart rate, Body temperature, Temperature control, Body weight, Males, Females, Adipose tissue

Subject Categories : Stress Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE