Relationship between heat storage and parameters of thermotolerance and fatigue in exertional heat stress

Siniša T. Mašić; Sonja Marjanović Sonja Marjanović; Jelena M.  Stojićević; Vanja M. Jovanović; Mirjana V. Joksimović; Danijela Ilić

doi:10.2298/VSP211012099M

Siniša T. Mašić Military Medical Academy, Institute of Hygiene, Belgrade, Serbia
Sonja Marjanović Sonja Marjanović University of Defence, Faculty of Medicine of the Military Medical Academy, Belgrade, Serbia
Jelena M. Stojićević Military Medical Academy, Institute of Hygiene, Belgrade, Serbia
Vanja M. Jovanović Military Medical Academy, Institute of Occupational Medicine, Belgrade, Serbia
Mirjana V. Joksimović Military Medical Academy, Institute of Nuclear Medicine, Belgrade, Serbia
Danijela Ilić University of Priština, Faculty of Medicine, Kosovska Mitrovica, Serbia

DOI: https://doi.org/10.2298/VSP211012099M

Keywords: telesna temperatura;, stres uzrokovan toplotom, poremećaji;, hormoni;, kadar, vojni;, napor, fizički.

Abstract

Uvod/Cilj. Procena rizika od nastanka zamora i nekog oblika toplotne bolesti je od velikog značaja za vojnu službu. Cilj ovog istraživanja bio je da se utvrdi povezanost između stepena akumulacije toplote i različitih psihofizioloških parametara toplotnog stresa, kao i mogućih perifernih markera zamora u populaciji vojnika izloženih toplotnom stresu kombinovanim sa fizičkim naporom. Metode. Petnaest mladih, zdravih, utreniranih i neaklimatizovanih muškaraca podvrgnuto je testu toplotnog stresa (TTS) tokom fizičke aktivnosti submaksimalnog opterećenja u uslovima povišene temperature spoljne sredine (29 °C) u klimatskoj komori. Na svakih 10 min registrovane su ili izračunavane vrednosti sledećih parametara termotolerancije: unutrašnje (timpanične) temperature (Tu), srednje temperature kože (Tsk), temperature tela (Tt), frekvence srčanog rada (FSR), akumulacije toplote (AT), indeksa fiziološkog napora (IFN), kao i perifernih markera zamora [koncentracije amonijaka, uree u krvi (BUN), laktat dehidrogenaze (LDH) kortizola i prolaktina] i subjektivnih parametara – osećaja toplote (OT) i stepena napora (SN). Rezultati. Vreme tolerancije variralo je između 45 i 75 min (srednja vrednost 63 ± 7,7 min). Prosečne vrednosti Tu, Tt i FSR konstantno su rasle tokom TTS, dok je Tsk dostigla plato nakon prvih 10 min. Vrednosti svih ispitivanih perifernih markera zamora bile su značajno veće nakon TTS u odnosu na vrednosti pre testa (amonijak 31,47 ± 7,29 vs. 11,8 ± 1,11 µmol/L, BUN 5,92 ± 0,73 vs. 4,69 ± 0,74 mmol/L, LDH 187,27 ± 28,49 vs. 152,73 ± 23,39 U/L, kortizol 743,43 ± 206,19 vs. 558,79 ± 113,34 mmol/L i prolaktin 418,08 ± 157,14 vs. 138,79 ± 92,83 μIU/mL). Zaključak. Rezultati su ukazali na povezanost između stepena akumulacije toplote i Tu, FSR, OT i SN, ali takođe i IFN. Koncentracije kortizola i, naročito, prolaktina pokazale su značajnu povezanost sa parametrima termotolerancije.

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