Exertional thermal strain, protective clothing and auxiliary cooling in dry heat: evidence for physiological but not cognitive impairment

Caldwell, Joanne; Patterson, Mark; Taylor, Nigel
October 2012
European Journal of Applied Physiology;Oct2012, Vol. 112 Issue 10, p3597
Academic Journal
Individuals exposed to extreme heat may experience reduced physiological and cognitive performance, even during very light work. This can have disastrous effects on the operational capability of aircrew, but such impairment could be prevented by auxiliary cooling devices. This hypothesis was tested under very hot-dry conditions, in which eight males performed 2 h of low-intensity exercise (~30 W) in three trials, whilst wearing biological and chemical protective clothing: temperate (control: 20°C, 30% relative humidity) and two hot-dry trials (48°C, 20% relative humidity), one without (experimental) and one with liquid cooling (water at 15°C). Physiological strain and six cognitive functions were evaluated (MiniCog Rapid Assessment Battery), and participants drank to sustain hydration state. Maximal core temperatures averaged 37.0°C (±0.1) in the control trial, and were significantly elevated in the experimental trial (38.9°C ± 0.3; P < 0.05). Similarly, heart rates peaked at 92 beats min (±7) and 133 beats min (±4; P < 0.05), respectively. Liquid cooling reduced maximal core temperatures (37.3°C ± 0.1; P < 0.05) and heart rates 87 beats min (±3; P < 0.05) in the heat, such that neither now differed significantly from the control trial ( P > 0.05). However, despite inducing profound hyperthermia and volitional fatigue, no cognitive degradation was evident in the heat ( P > 0.05). Since extensive dehydration was prevented, it appears that thermal strain in the absence of dehydration may have minimal impact upon cognitive function, at least as evaluated within this experiment.


Related Articles

  • Can a Novel Web-Based Computer Test Predict Poor Simulated Driving Performance? A Pilot Study With Healthy and Cognitive-Impaired Participants. Nef, Tobias; Müri, René M; Bieri, Rahel; Jäger, Michael; Bethencourt, Nora; Tarnanas, Ioannis; Mosimann, Urs P // Journal of Medical Internet Research;Oct2013, Vol. 15 Issue 10, p1 

    Background: Driving a car is a complex instrumental activity of daily living and driving performance is very sensitive to cognitive impairment. The assessment of driving-relevant cognition in older drivers is challenging and requires reliable and valid tests with good sensitivity and specificity...

  • Cognitive function in subclinical hypothyroidism in elderly. Bajaj, Sarita; Sachan, Shivam; Misra, Vatsala; Varma, Anurag; Saxena, Piyush // Indian Journal of Endocrinology & Metabolism;Nov/Dec2014, Vol. 18 Issue 6, p811 

    Aim: To study the association of cognitive function with subclinical hypothyroidism in elderly. Materials and Methods: It's a cross-sectional, case-control study of 103 patients (≥65 years) who met the criteria for subclinical hypothyroidism. Similarly 103 age, sex and education-matched...

  • Measuring cognitive change in subjects with prodromal Alzheimer's disease. Mura, T.; Proust-Lima, C.; Jacqmin-Gadda, H.; Akbaraly, T. N.; Touchon, J.; Dubois, B.; Berr, C. // Journal of Neurology, Neurosurgery & Psychiatry;Apr2014, Vol. 85 Issue 4, p363 

    Objective: To investigate the sensitivity of a large set of neuropsychological tests to detect cognitive changes due to prodromal Alzheimer's disease(AD); to compare their metrological properties in order to select a restricted number of these tests for the longitudinal follow-up of subjects...

  • Correcting the MoCA for Education: Effect on Sensitivity. Gagnon, Genevieve; Hansen, Kevin T.; Woolmore-Goodwin, Sarah; Gutmanis, Iris; Wells, Jennie; Borrie, Michael; Fogarty, Jennifer // Canadian Journal of Neurological Sciences;Sep2013, Vol. 40 Issue 5, p678 

    Objective: The goal of this study was to quantify the impact of the suggested education correction on the sensitivity and specificity of the Montreal Cognitive Assessment (MoCA). Method: Twenty-five outpatients with dementia and 39 with amnestic mild cognitive impairment (aMCI) underwent a...

  • Korrelation mentaler Aktivitäten mit kognitiven Funktionen in der Frühdiagnostik demenzieller Erkrankungen. Defrancesco, M.; Kemmler, G.; Huber, R.; Deisenhammer, E.A. // Der Nervenarzt;Mar2014, Vol. 85 Issue 3, p350 

    Introduction: Mental activities have been suggested to influence the risk and course of dementia. This study was performed in order to assess the association of various mental activities with diagnosis and cognitive functions in an elderly population. Methods: A total of 191 memory clinic...

  • Aerobic Exercise Boosts Cognitive Function in Patients With MCI. Sullivan, Michele G. // Neurology Reviews;Sep2013, Vol. 21 Issue 9, p28 

    The article discusses results of clinical trials presented by the physician Laura Baker at 2013 Alzheimer's Association International Conference held in the U.S. which reveals that aerobic exercise enhances cognitive functions in patients with mild cognitive impairment (MCI). Baker refers to two...

  • Association between intake of B vitamins and cognitive function in elderly Koreans with cognitive impairment. Hyesook Kim; Ggotpin Kim; Won Jang; Seong Yoon Kim; Namsoo Chang // Nutrition Journal;2014, Vol. 13 Issue 1, p81 

    Background It is possible that blood B vitamins level and cognitive function may be affected by dietary intake of these vitamins, no study however has yet been conducted on relationships between B vitamins intake and cognitive function among elderly population in Korea. This study examined the...

  • Perfil biopsicosocial de los muy mayores en Colima (80+). Molina, María Ángeles; Fernández-Ballesteros, Rocío // Salud Pública de México;nov/dic2012, Vol. 54 Issue 6, p569 

    No abstract available.

  • The Alcohol Paradox: Light-to-Moderate Alcohol Consumption, Cognitive Function, and Brain Volume. Davis, Benjamin J. K.; Vidal, Jean-Sebastian; Garcia, Melissa; Aspelund, Thor; van Buchem, Mark A.; Jonsdottir, Maria K.; Sigurdsson, Sigurdur; Harris, Tamara B.; Gudnason, Vilmundur; Launer, Lenore J. // Journals of Gerontology Series A: Biological Sciences & Medical ;Dec2014, Vol. 69 Issue 12, p1528 

    Background. Studies of older persons show consumption of light-to-moderate amounts of alcohol is positively associated with cognitive function and, separately, is negatively associated with total brain volume (TBV). This is paradoxical as generally, cognitive function is positively associated...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics