The effect of hyperhydration on physiological and perceived strain during treadmill exercise in personal protective equipment

  • David Hostler
  • Michael GallagherJr
  • Fredric L. Goss
  • Jennifer R. Seitz
  • Steven E. Reis
  • Robert J. Robertson
  • William E. Northington
  • Joe Suyama
Original Article

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.

Keywords

Thermoregulation Personal protective equipment Hydration Perceptual strain Physiologic strain 

References

  1. Anderson MJ, Cotter JD, Garnham AP, Casley DJ, Febbraio MA (2001) Effect of glycerol-induced hyperhydration on thermoregulation and metabolism during exercise in heat. Int J Sport Nutr Exerc Metab 11:315–333. doi:10.1097/00005768-200105001-01769 PubMedCrossRefGoogle Scholar
  2. Ayling JH (1986) Regional rates of sweat evaporation during leg and arm cycling. Br J Sports Med 20:35–37PubMedCrossRefGoogle Scholar
  3. Casa DJ, Maresh CM, Armstrong LE, Kavouras SA, Herrera JA, Hacker FT Jr, Keith NR, Elliott TA (2000) Intravenous versus oral rehydration during a brief period: responses to subsequent exercise in the heat. Med Sci Sports Exerc 32:124–133. doi:10.1097/00005768-200001000-00019 PubMedCrossRefGoogle Scholar
  4. Castellani JW, Maresh CM, Armstrong LE, Kenefick RW, Riebe D, Echegaray M, Casa D, Castracane VD (1997) Intravenous vs. oral rehydration: effects on subsequent exercise-heat stress. J Appl Physiol 82:799–806PubMedGoogle Scholar
  5. Cheung SS (2007) Hyperthermia and voluntary exhaustion: integrating models and future challenges. Appl Physiol Nutr Metab 32:808–817. doi:10.1139/H07-043 PubMedCrossRefGoogle Scholar
  6. Cheung SS, McLellan TM (1998) Influence of hydration status and fluid replacement on heat tolerance while wearing NBC protective clothing. Eur J Appl Physiol Occup Physiol 77:139–148. doi:10.1007/s004210050312 PubMedCrossRefGoogle Scholar
  7. Gagge AP, Stolwijk AJ, Saltin B (1969) Comfort and thermal sensations and associated physiological responses during exercise at various ambient temperatures. Environ Res 2:209–229. doi:10.1016/0013-9351(69)90037-1 PubMedCrossRefGoogle Scholar
  8. Harris J, Benedict F (1918) A biometric study of human basal metabolism. Proc Natl Acad Sci USA 4:370–373. doi:10.1073/pnas.4.12.370 PubMedCrossRefGoogle Scholar
  9. Jackson AS, Pollock ML (1977) Prediction accuracy of body density, lean body weight, and total body volume equations. Med Sci Sports 9:197–201PubMedGoogle Scholar
  10. Kenefick RW, Maresh CM, Armstrong LE, Castellani JW, Riebe D, Echegaray ME, Kavorous SA (2000) Plasma vasopressin and aldosterone responses to oral and intravenous saline rehydration. J Appl Physiol 89:2117–2122PubMedGoogle Scholar
  11. Kenefick RW, O’Moore KM, Mahood NV, Castellani JW (2006) Rapid IV versus oral rehydration: responses to subsequent exercise heat stress. Med Sci Sports Exerc 38:2125–2131. doi:10.1249/01.mss.0000235358.39555.80 PubMedCrossRefGoogle Scholar
  12. Latzka WA, Sawka MN (2000) Hyperhydration and glycerol: thermoregulatory effects during exercise in hot climates. Can J Appl Physiol 25:536–545PubMedGoogle Scholar
  13. Latzka WA, Sawka MN, Montain SJ, Skrinar GS, Fielding RA, Matott RP, Pandolf KB (1997) Hyperhydration: thermoregulatory effects during compensable exercise-heat stress. J Appl Physiol 83:860–866PubMedGoogle Scholar
  14. Latzka WA, Sawka MN, Montain SJ et al (1998) Hyperhydration: tolerance and cardiovascular effects during uncompensable exercise-heat stress. J Appl Physiol 84:1858–1864PubMedGoogle Scholar
  15. Maresh CM, Herrara-Soto JA, Armstrong LE et al (2001) Perceptual responses in the heat after brief intravenous versus oral rehydration. Med Sci Sports Exerc 33(6):1039–1045. doi:10.1097/00005768-200106000-00025 PubMedCrossRefGoogle Scholar
  16. McLellan TM, Cheung SS (2000) Impact of fluid replacement on heat storage while wearing protective clothing. Ergonomics 43:2020–2030. doi:10.1080/00140130050201454 PubMedCrossRefGoogle Scholar
  17. Montain SJ, Sawka MN, Cadarette BS et al (1994) Physiological tolerance to uncompensable heat stress: effects of exercise intensity, protective clothing, and climate. J Appl Physiol 77:216–222PubMedGoogle Scholar
  18. Moran DS, Montain SJ, Pandolf KB (1998) Evaluation of different levels of hydration using a new physiological strain index. Am J Physiol 275(Regul Integr Comp Physiol 45):R854–R860Google Scholar
  19. Noakes TD (1998) Maximal oxygen uptake: “classical” versus “contemporary” viewpoints: a rebuttal. Med Sci Sports Exerc 30:1381–1398. doi:10.1097/00005768-199809000-00007 PubMedCrossRefGoogle Scholar
  20. Noakes TD, St Clair Gibson A et al (2005) From catastrophe to complexity: a novel model of integrative central neural regulation of effort and fatigue during exercise in humans: summary and conclusions. Br J Sports Med 39:120–124. doi:10.1136/bjsm.2003.010330 PubMedCrossRefGoogle Scholar
  21. Northington WE, Suyama J, Goss FL et al (2007) Physiological responses during graded treadmill exercise in chemical-resistant personal protective equipment. Prehosp Emerg Care 11:394–398. doi:10.1080/10903120701536933 PubMedCrossRefGoogle Scholar
  22. O’Brien C, Hoyt RW, Buller MJ et al (1998) Telemetry pill measurement of core temperature in humans during active heating and cooling. Med Sci Sports Exerc 30:468–472. doi:10.1097/00005768-199803000-00020 PubMedGoogle Scholar
  23. Riebe D, Maresh CM, Armstrong LE et al (1997) Effects of oral and intravenous rehydration on ratings of perceived exertion and thrist. Med Sci Sports Exerc 29:117–124. doi:10.1097/00005768-199701000-00017 PubMedGoogle Scholar
  24. Toner MM, Drolet LL, Pandolf KB (1986) Perceptual and physiological responses during exercise in cool and cold water. Percept Mot Skills 62:211–220PubMedGoogle Scholar
  25. Wilkinson DM, Carter JM, Richmond VL et al (2008) The effect of cool water ingestion on gastrointestinal pill temperature. Med Sci Sports Exerc 40:523–528. doi:10.1249/01.mss.0000322518.55560.7f PubMedCrossRefGoogle Scholar
  26. Tikuisis P, McLellan TM, Selkirk G (2002) Perceptual versus physiological heat strain during exercise-heat stress. Med Sci Sports Exerc 34:1454–1461. doi:10.1097/00005768-200209000-00009 PubMedCrossRefGoogle Scholar
  27. Utter AC, Robertson RJ, Green JM et al (2004) Validation of the Adult OMNI Scale of perceived exertion for walking/running exercise. Med Sci Sports Exerc 36:1776–1780. doi:10.1249/01.MSS.0000142310.97274.94 PubMedCrossRefGoogle Scholar
  28. Vokac Z, Kopke V, Keul P (1976) Physiological responses and thermal, humidity & comfort sensations in wear trials with cotton & polypropylene vests. Text Res J 46:30–38Google Scholar

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • David Hostler
    • 1
  • Michael GallagherJr
    • 2
  • Fredric L. Goss
    • 2
  • Jennifer R. Seitz
    • 2
  • Steven E. Reis
    • 1
    • 3
  • Robert J. Robertson
    • 2
  • William E. Northington
    • 1
  • Joe Suyama
    • 1
  1. 1.Emergency Responder Human Performance Lab, Department of Emergency MedicineUniversity of PittsburghPittsburghUSA
  2. 2.Department of Health and Physical ActivityUniversity of PittsburghPittsburghUSA
  3. 3.Cardiovascular InstituteUniversity of PittsburghPittsburghUSA

Personalised recommendations