Accession Number : ADA186460

Title :   Respiratory and Cardiovascular Responses to Cold Stress Following Repeated Cold Water Immersion,

Corporate Author : ARMY RESEARCH INST OF ENVIRONMENTAL MEDICINE NATICK MA

Personal Author(s) : Muza, S R ; Young, A J ; Sawka, M N ; Bogart, J E ; Pandolf, K B

PDF Url : ADA186460

Report Date : Jul 1987

Pagination or Media Count : 32

Abstract : The effects of cold acclimation (CA) on the cardiorespiratory responses to cold air and water stress tests (CST) were studied in seven males before and after a CA program of daily 90 min cold water (18 C) immersions repeated five times a week for five consecutive weeks. The CST consisted of a 90 min resting exposure to cold air or water during which rectal temperature (T sub re), oxygen consumption (VO2), carbon dioxide production (VCO2), minute ventilation (V sub E), heart rate (HR), cardiac output (Q) and blood pressure (BP) were periodically measured. In cold air following CA, the VO2 at 10 minutes was lower post than pre CA, however, no differences were found in cold water. The (V sub E) increased during CST as a function of VCO2. The CA did not affect the (V sub E)-VCO2 relationship or the pattern of breathing during CST in cold air or water. The CA had no effect on Q or (a-V) O2 difference, which both increased during the first 45 min of CST, then remained stable. BP increased significantly during the first cold water exposure, but not during the last cold water immersion. These data indicate the CA attenuated the onset of metabolic heat production during CST in air but did not alter its ultimate magnitude or the relationships between the cardiorespiratory variables and metabolic requirements. Also the thermoregulatory adjustments associated with CA altered the control of blood pressure during acute cold stress.

Descriptors :   *CARDIOVASCULAR SYSTEM, *RESPIRATORY SYSTEM, *HYPOTHERMIA, *STRESS(PHYSIOLOGY), ACCLIMATIZATION, AIR, BLOOD PRESSURE, BODY TEMPERATURE, CARBON DIOXIDE, HEART, HEART RATE, HEAT PRODUCTION(BIOLOGY), LIQUID IMMERSION TESTS, LOW TEMPERATURE, MALES, METABOLISM, OXYGEN CONSUMPTION, PATTERNS, RECTUM, RESPIRATION, RESPONSE(BIOLOGY), TEST AND EVALUATION, VARIABLES, VENTILATION, WATER, COLD WEATHER TESTS, EXPOSURE(PHYSIOLOGY), TEMPERATURE CONTROL

Subject Categories : Stress Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE