The Effects of Cold and Lower Body Negatvie Pressure on Cardiovascular and Thermoregulatory Homeostasis
Year: 2012
Type: article
Abstract: Lower body negative pressure (LBNP) sequesters blood from the thorax into dependent regions of the pelvis and legs, effectively decreasing central blood volume.Cold exposure will alter central blood volume in response to variations in core and skin temperature.This may lead to improved tolerance of LBNP.The purpose of this study is to determine the effects of cold exposure and lower body negative pressure on cardiovascular and thermoregulatory variables.Eleven males (20.3 ± 2.7) underwent two 20-minute exposures to LBNP (AMB and COLD).During one trial the subjects were exposed to cold air (10°C) the other they were exposed to ambient temperature (23°C).The trials consisted of a 100-minute pre-LBNP period followed by a 20-minute exposure to LBNP and then a 15-minute recovery period.Cardiovascular variables were recorded every 30 minutes using bioimpedance.Rectal temperature and skin temperatures were recorded every 15 minutes and thermal sensation was assessed every 15 minutes using the Gagge and Modified Gagge scales.A repeated measures ANOVA demonstrated a significant condition x time interaction for rectal temperature (T re ) (p = 0.002), mean skin temperature (p < 0.05), thermal sensation (p = 0.002), modified thermal sensation (p < 0.05) and tissue insulation (p < 0.05).There was also a significant condition x time interaction for mean arterial pressure (p = 0.014), and cerebral oxygenation (p = 0.034).From these data, it may be suggested that cold alters the physiological response to LBNP.My first acknowledgment is to God.This has not been easy and God has provided during this entire project.I want to acknowledge Dr. Ellen Glickman.I was dead in the water and I needed someone to back me up and she did.Without that, I would have never finished.I will be forever grateful as this is one of the greatest accomplishments of my life
Author: David J. Kean
Institution: Kent State University
Language: English
Subfield: Physiology (medical)
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W2612708822