title: The effect of hyperhydration on physiological and perceived strain during treadmill exercise in personal protective equipment.
abstract: Work in personal protective equipment (PPE) impairs thermoregulation causing cardiovascular stress, increased core body temperature, and hypohydration. We examined the effect of pretreating first responders performing treadmill exercise in PPE with an infusion of normal saline on physiological and perceptual strain. Ten (eight males, two females) euhydrated subjects performed treadmill exercise on two occasions wearing a chemical resistant coverall, air purifying respirator, butyl gloves, and heavy boots. During the hyperhydration session, normal saline was rapidly infused through an arm vein prior to donning PPE. Exercise duration and maximum core temperature did not differ between euhydrated and hyperhydrated conditions. Perceptual strain index (PeSI) was higher than physiological strain index (PhSI) in the euhydrated condition (P = 0.002) but neither index differed between the control and experimental conditions. Intravenous hyperhydration did not reduce physiological stress, increase exercise, or influence perceptual strain time when compared to the euhydrated condition in moderately fit individuals.
authors.affiliation: Emergency Responder Human Performance Lab, Department of Emergency Medicine, University of Pittsburgh, 230 McKee Place, Suite 400, Pittsburgh, PA 15213, USA. hostlerdp@upmc.edu
authors.forename: David
authors.initials: D
authors.lastname: Hostler
authors.forename: Michael
authors.initials: M
authors.lastname: Gallagher
authors.forename: Fredric L
authors.initials: FL
authors.lastname: Goss
authors.forename: Jennifer R
authors.initials: JR
authors.lastname: Seitz
authors.forename: Steven E
authors.initials: SE
authors.lastname: Reis
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Robertson
authors.forename: William E
authors.initials: WE
authors.lastname: Northington
authors.forename: Joe
authors.initials: J
authors.lastname: Suyama
mesh_terms: D000328:Adult; D001831:Body Temperature / Q000502:physiology*; D001833:Body Temperature Regulation / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D005260:Female; D018882:Heat Stress Disorders / Q000517:prevention & control*; D006801:Humans; D008297:Male; D005082:Physical Exertion / Q000502:physiology; D011446:Prospective Studies; D011481:Protective Clothing / Q000009:adverse effects; D011482:Protective Devices / Q000009:adverse effects*; D012965:Sodium Chloride / Q000008:administration & dosage; D013997:Time Factors
chemical_list: D012965:Sodium Chloride