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Encapsulated Environment

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Abstract

In many occupational settings, clothing must be worn to protect individuals from hazards in their work environment. However, personal protective clothing (PPC) restricts heat exchange with the environment due to high thermal resistance and low water vapor permeability. As a consequence, individuals who wear PPC often work in uncompensable heat stress conditions where body heat storage continues to rise and the risk of heat injury is greatly enhanced. Tolerance time while wearing PPC is influenced by three factors: (i) initial core temperature (Tc), affected by heat acclimation, precooling, hydration, aerobic fitness, circadian rhythm, and menstrual cycle (ii) Tc tolerated at exhaustion, influenced by state of encapsulation, hydration, and aerobic fitness; and (iii) the rate of increase in Tc from beginning to end of the heat‐stress exposure, which is dependent on the clothing characteristics, thermal environment, work rate, and individual factors like body composition and economy of movement. Methods to reduce heat strain in PPC include increasing clothing permeability for air, adjusting pacing strategy, including work/rest schedules, physical training, and cooling interventions, although the additional weight and bulk of some personal cooling systems offset their intended advantage. Individuals with low body fatness who perform regular aerobic exercise have tolerance times in PPC that exceed those of their sedentary counterparts by as much as 100% due to lower resting Tc, the higher Tc tolerated at exhaustion and a slower increase in Tc during exercise. However, questions remain about the importance of activity levels, exercise intensity, cold water ingestion, and plasma volume expansion for thermotolerance. Published 2013. Compr Physiol 3:1363‐1391, 2013.

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Figure 1. Figure 1.

The energy cost of movement while wearing a multilayered Arctic clothing ensemble or carrying equivalent weight as a single‐layer uniform with weighted belt. Adapted from Teitlebaum and Goldman ().

Figure 2. Figure 2.

A schematic representation of sweat production and its vaporization through clothing together with sweat lost through dripping off the skin surface and condensation in the clothing layers. Reproduced, with permission, from Cheung ().

Figure 3. Figure 3.

The relationship between tolerance time and metabolic rate when wearing Canadian Forces nuclear, biological, and chemical protective clothing in different environmental conditions. Solid and dotted lines represent data from various environmental conditions derived from McLellan () and McLellan et al. ().

Figure 4. Figure 4.

The effects of 12 days of heat acclimation to a hot and humid environment on tolerance time during cycling at a constant power output. Note that the increase in tolerance time following the heat acclimation is due to the decrease in resting core temperature. The figure is derived from data in Nielsen et al. ().

Figure 5. Figure 5.

Rectal temperature in the morning during 12 days of heat acclimation (HA) with minimal recovery and 3, 7, and 18 days later. Please note that the reduction in core temperature is not seen during, but after HA. Reproduced, with permission, from Daanen et al. ().

Figure 6. Figure 6.

Rectal temperature after 60 min exercise during heat acclimation for 10 days followed by reacclimation 26 days later for 7 days. Note that even after 26 days the core temperature is the same as the end of the initial heat acclimation period. Reproduced, with permission, from Weller et al. ().

Figure 7. Figure 7.

The change in core temperature while wearing either the current personal protective ensemble consisting of the combat uniform and overgarment concept or new stand‐alone chemical and biological (CB) uniforms. During the low dress state minimal protection is required and only the combat uniform is worn. However, during the high dress state full encapsulation and maximum protection is required, necessitating the use of the overgarment. The use of the new CB uniforms does not require an overgarment since the CB protection is already included within the clothing material. Notice after 60 min at the beginning of the transition from the low to high dress state core temperature is higher for the new CB uniform.

Figure 8. Figure 8.

Heart rate and rectal temperature tolerated at exhaustion during low exercise intensity of 165 W·m2 with a tolerance time of 105 min versus high exercise intensity of 260 W·m2 and tolerance time of 60 min. The asterisk indicates a significant difference between the low and high exercise intensities.

Figure 9. Figure 9.

Sample size of participants from each training status throughout a passive heating protocol. The highly fit (circles), moderately fit (squares), and lower fit (triangles) groups began with similar sample sizes, although the majority of the lower fit participants were unable to complete the protocol. Reproduced, with permission, from Morrison et al. ().

Figure 10. Figure 10.

The theoretical effect of cooling on tolerance time in protective equipment based on modeling studies. Reproduced, with permission, from Pandolf et al. ().

Figure 11. Figure 11.

The effects of hand and forearm submersion in 18°C water for 20 min on the increase in rectal temperature (expressed as delta Tre) following 50 min of exercise at 35°C while wearing full firefighting PPC. The asterisk indicates a significant difference between the hand and forearm immersion trial compared with the condition that involved passive cooling when some of the firefighting PPC was removed during the 20‐min rest periods. Tolerance time was increased significantly from 108 ± 14 min with passive cooling to 179 ± 50 min with hand and forearm submersion. Adapted from Selkirk et al. ().

Figure 12. Figure 12.

A schematic representation of the tolerance time during uncompensable heat stress for a sedentary untrained individual (A) and the influence of raising the initial resting core temperature due to circadian rhythm, menstrual phase or minor (B) or severe (C) hypohydration, lowering resting core temperature through heat acclimation or precooling strategies (D) and a decrease in body fatness, an increase in gross movement efficiency or providing cooling during encapsulation (E). Also depicted is the improvement in heat tolerance for an endurance trained individual (F) who can tolerate much higher core temperatures at exhaustion. The values depicted on the x‐axis represent mean changes that would be expected from the average response observed during light exercise. Individual effects could be much greater or less.



Figure 1.

The energy cost of movement while wearing a multilayered Arctic clothing ensemble or carrying equivalent weight as a single‐layer uniform with weighted belt. Adapted from Teitlebaum and Goldman ().



Figure 2.

A schematic representation of sweat production and its vaporization through clothing together with sweat lost through dripping off the skin surface and condensation in the clothing layers. Reproduced, with permission, from Cheung ().



Figure 3.

The relationship between tolerance time and metabolic rate when wearing Canadian Forces nuclear, biological, and chemical protective clothing in different environmental conditions. Solid and dotted lines represent data from various environmental conditions derived from McLellan () and McLellan et al. ().



Figure 4.

The effects of 12 days of heat acclimation to a hot and humid environment on tolerance time during cycling at a constant power output. Note that the increase in tolerance time following the heat acclimation is due to the decrease in resting core temperature. The figure is derived from data in Nielsen et al. ().



Figure 5.

Rectal temperature in the morning during 12 days of heat acclimation (HA) with minimal recovery and 3, 7, and 18 days later. Please note that the reduction in core temperature is not seen during, but after HA. Reproduced, with permission, from Daanen et al. ().



Figure 6.

Rectal temperature after 60 min exercise during heat acclimation for 10 days followed by reacclimation 26 days later for 7 days. Note that even after 26 days the core temperature is the same as the end of the initial heat acclimation period. Reproduced, with permission, from Weller et al. ().



Figure 7.

The change in core temperature while wearing either the current personal protective ensemble consisting of the combat uniform and overgarment concept or new stand‐alone chemical and biological (CB) uniforms. During the low dress state minimal protection is required and only the combat uniform is worn. However, during the high dress state full encapsulation and maximum protection is required, necessitating the use of the overgarment. The use of the new CB uniforms does not require an overgarment since the CB protection is already included within the clothing material. Notice after 60 min at the beginning of the transition from the low to high dress state core temperature is higher for the new CB uniform.



Figure 8.

Heart rate and rectal temperature tolerated at exhaustion during low exercise intensity of 165 W·m2 with a tolerance time of 105 min versus high exercise intensity of 260 W·m2 and tolerance time of 60 min. The asterisk indicates a significant difference between the low and high exercise intensities.



Figure 9.

Sample size of participants from each training status throughout a passive heating protocol. The highly fit (circles), moderately fit (squares), and lower fit (triangles) groups began with similar sample sizes, although the majority of the lower fit participants were unable to complete the protocol. Reproduced, with permission, from Morrison et al. ().



Figure 10.

The theoretical effect of cooling on tolerance time in protective equipment based on modeling studies. Reproduced, with permission, from Pandolf et al. ().



Figure 11.

The effects of hand and forearm submersion in 18°C water for 20 min on the increase in rectal temperature (expressed as delta Tre) following 50 min of exercise at 35°C while wearing full firefighting PPC. The asterisk indicates a significant difference between the hand and forearm immersion trial compared with the condition that involved passive cooling when some of the firefighting PPC was removed during the 20‐min rest periods. Tolerance time was increased significantly from 108 ± 14 min with passive cooling to 179 ± 50 min with hand and forearm submersion. Adapted from Selkirk et al. ().



Figure 12.

A schematic representation of the tolerance time during uncompensable heat stress for a sedentary untrained individual (A) and the influence of raising the initial resting core temperature due to circadian rhythm, menstrual phase or minor (B) or severe (C) hypohydration, lowering resting core temperature through heat acclimation or precooling strategies (D) and a decrease in body fatness, an increase in gross movement efficiency or providing cooling during encapsulation (E). Also depicted is the improvement in heat tolerance for an endurance trained individual (F) who can tolerate much higher core temperatures at exhaustion. The values depicted on the x‐axis represent mean changes that would be expected from the average response observed during light exercise. Individual effects could be much greater or less.

References
 1. Amos D, Hansen R. The physiological strain induced by a new low burden chemical protective ensemble. Aviat Space Environ Med 68: 126‐131, 1997.
 2. Aoyagi Y, McLellan TM, Shephard RJ. Effects of training and acclimation on heat tolerance in exercising men wearing protective clothing. Eur J Appl Physiol 68: 234‐245, 1994.
 3. Aoyagi Y, McLellan TM, Shepard RJ. Effects of 6 versus 12 days of heat acclimation on heat tolerance in lightly exercising men wearing protective clothing. Eur J Appl Physiol 71: 187‐196, 1995.
 4. Armstrong LE, Johnson EC, Casa DJ, Ganio MS, McDermott BP, Yamamoto LM, Lopez RM, Emmanuel H. The American football uniform: uncompensable heat stress and hyperthermic exhaustion. J Athl Train 45: 117‐127, 2010.
 5. Armstrong LE, Pandolf KB. Physical training, cardiorespiratory physical fitness and exercise‐heat tolerance. In: Pandolf KB, Sawka MN, Gonzalez RR, editors. Human Performance Physiology and Environmental Medicine in Terrestrial Extremes. Indianapolis: Benchmark Press, 1988, p. 199‐226.
 6. Atterbom HA, Mossman PB. Physiological effects on work performance of vapor‐barrier clothing and full‐face respirator. J Occup Med 20: 45‐51, 1978.
 7. Avellini BA, Shapiro Y, Fortney SM, Wenger CB, Pandolf KB. Effects of heat tolerance of physical training in water and on land. J Appl Physiol 53: 1291‐1298, 1982.
 8. Barlett HL, Hodgson JL, Kollias J. Effect of respiratory valve dead space on pulmonary ventilation at rest and during exercise. Med Sci Sports Exerc 4: 132‐137, 1972.
 9. Barwood MJ, Newton PS, Tipton MJ. Ventilated vest and tolerance for intermittent exercise in hot, dry conditions with military clothing. Aviat Space Environ Med 80: 353‐359, 2009.
 10. Beckett WS, Davis JE, Vroman N. Heat stress associated with the use of vapor‐barrier garments. J Occup Med 28: 411‐414, 1986.
 11. Bensel C. Soldier performance and functionality: impact of chemical protective clothing. Mil Psychol 9: 287‐300, 1997.
 12. Bernard T, Ashley C, Trentacosta J, Kapur V, Tew S. Critical heat stress evaluation of clothing ensembles with different levels of porosity. Ergonomics 53: 1048‐1058, 2010.
 13. Bomalaski SH. Thermal stress in seven types of chemical defense ensembles during moderate exercise in hot environments Armstrong Lab TR‐1992‐0141 XC‐AL. Brooks AFB, 1993.
 14. Bomalaski SH, Chen YT, Constable SH. Continuous and intermittent personal microclimate cooling strategies. Aviat Space Environ Med 66: 745‐750, 1995.
 15. Bouskill LM, Havenith G, Kuklane K. Relationship Between Clothing Ventilation and Thermal Insulation. Am Ind Hyg Assoc J 63: 262‐268, 2002.
 16. Brown PI, McLellan TM, Linnane DM, Wilkinson DM, Richmond VL, Horner FE, Blacker SD, Rayson MP. Influence of hydration volume and ambient temperature on physiological responses while wearing CBRN protective clothing. Ergonomics 53: 1484‐1499, 2010.
 17. Buono MJ, Heaney JH, Canine KM. Acclimation to humid heat lowers resting core temperature. Am J Physiol 274: R1295‐R1299, 1998.
 18. Burdon CA, Johnson NA, Chapman PG, O'Connor HT. Influence of beverage temperature on palatability and fluid ingestion during endurance exercise: A systematic review. Int J Sports Nutr Exerc Metab 22: 199‐211, 2012.
 19. Butcher SJ, Jones RL, Eves ND, Petersen SR. Work of breathing is increased during exercise with the self‐contained breathing apparatus regulator. Appl Physiol Nutr Metab 31: 693‐701, 2006.
 20. Cadarette BS, Blanchard L, Staab JE, Kolka MA, Sawka MN. Heat Stress When Wearing Body Armor. Natick, MA: USARIEM, 2001, pp. 1‐20.
 21. Cadarette BS, Sawka MN, Toner MM, Pandolf KB. Aerobic fitness and the hypohydration response to exercise‐heat stress. Aviat Space Environ Med 55: 507‐512, 1984.
 22. Cain BJ, McLellan TM. A model of evaporation from the skin while wearing protective clothing. Int J Biometerol 41: 183‐193, 1998.
 23. Caldwell J, Caldwell J, Salter C. Effects of chemical protective clothing and heat stress on army helicopter pilot performance. Mil Psychol 9: 315‐328, 1997.
 24. Caldwell JN, Engelen L, Henst Cvd, Patterson MJ, Taylor NAS. The interaction of body armor, low‐intensity exercise, and hot‐humid conditions on physiological strain and cognitive function. Mil Med 176: 488‐493, 2011.
 25. Caretti DM. Assessment of the thermal load attributable to protective masks. Edgewood Chemical Biological Center Scientific Conference on Chemical and Biological Defense Reseach, Hunt Valley, MD, 2001.
 26. Carter BJ, Cammermeyer M. Emergence of real casualties during simulated chemical warfare training under high heat conditions. Milit Med 150: 657‐665, 1985.
 27. Carter III R, Cheuvront SN, Williams JO, Kolka MA, Stephenson LA, Sawka MN, Amoroso PJ. Epidemiology of hospitalizations and deaths from heat illness in soldiers. Med Sci Sports Exerc 37: 1338‐1344, 2005.
 28. Chang S, Gonzalez R. Benefit of heat acclimation is limited by the evaporative potential when wearing chemical protective clothing. Ergonomics 42: 1038‐1050, 1999.
 29. Chen KY, Acra SA, Donahue CL, Sun M, Buchowski MS. Efficiency of walking and stepping: Relationship to body fatness. Obes Res 12: 982‐989, 2004.
 30. Chen YS, Fan J, Qian X, Zhang W. Effect of garment fit on thermal insulation and evaporative resistance. J Text Res 74: 742‐748, 2004.
 31. Chen YS, Fan J, Zhang W. Clothing thermal insulation during sweating. Text Res J 73: 152‐157, 2003.
 32. Cheung SS. Advanced Environmental Exercise Physiology. Champaign, IL: Human Kinetics, 2010.
 33. Cheung SS, McLellan TM. Heat acclimation, aerobic fitness, and hydration effects on tolerance during uncompensable heat stress. J Appl Physiol 84: 1731‐1739, 1998.
 34. Cheung SS, McLellan TM. Influence of hydration status and fluid replacement on heat tolerance while wearing NBC protective clothing. Eur J Appl Physiol 77: 139‐148, 1998.
 35. Cheung SS, McLellan TM. Influence of short‐term aerobic training and hydration status on tolerance to uncompensable heat stress. Eur J Appl Physiol 78: 50‐58, 1998.
 36. Cheung SS, McLellan TM. Comparison of short‐term aerobic training and high aerobic power on tolerance to uncompensable heat stress. Aviat Space Environ Med 70: 637‐643, 1999.
 37. Cheung SS, McLellan TM, Tenaglia SA. The thermophyisology of uncompensable heat stress. Sports Med 29: 329‐359, 2000.
 38. Cheung SS, Petersen SR, and McLellan TM. Physiological strain and countermeasures with firefighting. Scand J Med Sci Sports 20 (Suppl. 3): 103‐116, 2010.
 39. Cheuvront SN, Goodman DA, Kenefick RW, Montain SJ, Sawka MN. Impact of a protective vest and spacer garment on exercise‐heat strain. Eur J Appl Physiol 102: 577‐583, 2008.
 40. Cheuvront SN, Kolka MA. Efficacy of intermittent, regional microclimate cooling. J Appl Physiol 94: 1841‐1848, 2003.
 41. Chinevere TD, Cadarette BS, Goodman DA, Ely BR, Cheuvront SN, Sawka MN. Efficacy of body ventilation system for reducing strain in warm and hot climates. Eur J Appl Physiol 103: 307‐314, 2008.
 42. Cole R. Heat stroke during training with nuclear, biological and chemical protective clothing: Case report. Mil Med 148: 624‐625, 1983.
 43. Constable SH, Bishop PA, Nunneley SA, Chen T. Intermittent microclimate cooling during rest increases work capacity and reduces heat stress. Ergonomics 37: 277‐285, 1994.
 44. Convertino VA, Armstrong LE, Coyle EF, Mack GW, Sawka MN, Senay LC Jr., Sherman MW. American College of Sports Medicine position stand. Exercise and fluid replacement. Med Sci Sports Exerc 28: i‐vii, 1996.
 45. Cortili G, Mognoni P, Saibene F. Work tolerance and physiological responses to thermal environment wearing protective NBC clothing. Ergonomics 39: 620‐633, 1996.
 46. Craig FN, Garren HW, Frankel H, Blevins WV. Heat load and voluntary tolerance time. J Appl Physiol 6: 634‐644, 1954.
 47. Craig FN, Moffitt JT. Evaporative cooling of men in wet clothing. J Appl Physiol 33: 331‐336, 1972.
 48. Cunningham DA, Rechnitzer PA, Pearce ME, Donner AP. Determinants of self‐selected walking pace across ages 19 to 66. J Gerontol 37: 560‐564, 1982.
 49. D'Urzo AD, Chapman KR, Rebuck AS. Effect of inspiratory resistive loading on control of ventilation during progressive exercise. J Appl Physiol 62: 134‐140, 1987.
 50. Daanen HAM. Deterioration of manual performance in cold and windy climates. AGARD Conference Proceedings 540: 15‐1‐15‐10, 1993.
 51. Daanen HAM. Finger cold‐induced vasodilation: A review. Eur J Appl Physiol 89: 411‐426, 2003.
 52. Daanen HAM. Manual performance deterioration in the cold estimated using the wind chill equivalent temperature. Ind Health 47: 262‐270, 2010.
 53. Daanen HAM, Hatcher K, Havenith G. Determination of clothing microclimate volume. In: Tochihara Y, Ohnaka T, editors. Environmental Ergonomics. Elsevier Ergonomics Book Series, 2005, p. 361‐365.
 54. Daanen HAM, Jonkman AG, Layden JD, Linnane DM, Weller AS. Optimising the acquisition and retention of heat acclimation. Int J Sports Med 32: 822‐828, 2011.
 55. Dawson B. Exercise training in sweat clothing in cool conditions to improve heat tolerance. Sports Med 17: 233‐244, 1994.
 56. DenHartog EA, Heus R. Positive pressure breathing during rest and exercise. Appl Ergonomics 34: 185‐194, 2003.
 57. Donoghue AM, Sinclair MJ, Bates GP. Heat exhaustion in a deep underground metalliferous mine. Occup Environ Med 57: 165‐174, 2000.
 58. Dorman LE, Havenith G. The effects of protective clothing on energy consumption during different activities. Eur J Appl Physiol 105: 463‐470, 2009.
 59. Dreger RW, Jones RL, Petersen SR. Effects of the self‐contained breathing apparatus and fire protective clothing on maximal oxygen uptake. Ergonomics 49: 911‐920, 2006.
 60. Duffield R, Green R, Castle P, Maxwell N. Precooling can prevent the reduction of self‐paced exercise intensity in the heat. Med Sci Sports Exerc 42: 577‐584, 2010.
 61. Duggan A. Energy cost of stepping in NBC and cold weather protective clothing. Ergonomics 31: 3‐11, 1986.
 62. Duncan EJS, McLellan TM, Gudgin‐Dickson EF. Canadian military CBRN protective clothing: Towards a new paradigm for protection and thermal burden. Improving Comfort in Clothing. Cambridge, UK: Woodhead Publishing Limited, 2010.
 63. Epstein Y, Moran DS. Thermal comfort and the heat stress indices. Ind Health 44: 388‐398, 2006.
 64. Eves ND, Jones RL, Petersen SR. The influence of the self‐contained breathing apparatus (SCBA) on ventilatory function and maximal exercise. Appl Physiol Nutr Metab 30: 507‐519, 2005.
 65. Fanger PO. Thermal Comfort: Analysis and Applications in Environmental Engineering. Copenhagen, Denmark: Danish Technical Press, 1970.
 66. Flouris AD, Cheung SS. Design and control optimization of microclimate liquid cooling systems underneath protective clothing. Ann Biomed Eng 34: 359‐372, 2006.
 67. Fox RH, Goldsmith R. Heat Acclimatization by controlled hyperthermia in hot‐dry and hot‐wet climates. J Appl Physiol 22: 39‐46, 1967.
 68. Fox RH, Goldsmith R, Kidd DJ, Lewis HE. Blood flow and other thermoregulatory changes with acclimatization to heat. J Physiol (London) 166: 548‐562, 1963.
 69. Frim J, Michas RD, Cain B. Personal cooling garment performance: A parametric study. In: Shapiro Y, Moran DS, Epstein Y, editors. Environmental Ergonomics. Recent Progress and New Frontiers. London and Tel Aviv: Freund Publishing House, Ltd., 1996.
 70. Fudge BW, Easton C, Kingsmore D, Kiplamai FK, Onywera VO, Westerterp KR, Kayser B, Noakes TD, Pitsiladis YP. Elite Kenyan endurance runners are hydrated day‐to‐day with ad libitum fluid intake. Med Sci Sports Exerc 40: 1171‐1179, 2008.
 71. Gao C, Kuklane K, Holmér I. Cooling vests with phase change materials: The effects of melting temperature on heat strain alleviation in an extremely hot environment. Eur J Appl Physiol 111: 1207‐1216, 2011.
 72. Gephart FC, Dubois EF. Clinical calorimetry, fourth paper. The determination of the basal metabolism of normal men and the effect of food. Arch Int Med 15: 833‐845, 1915.
 73. Giesbrecht G, Jamieson C, Cahill F. Cooling hyperthermic firefighters by immersing forearms and hands in 10 degrees C and 20 degrees C water. Aviat Space Environ Med 78: 561‐567, 2007.
 74. Givoni B, Goldman RF. Predicting rectal tmeperature response to work, environment, and clothing. J Appl Physiol 32: 812‐822, 1972.
 75. Goldman RF. Tolerance time for work in the heat when wearing CBR protective clothing. Milit Med 128: 776‐786, 1963.
 76. Goldman RF. Physiological costs of body armor. Milit Med 134: 204‐210, 1969.
 77. Goldman RF. Clothing design fo comfort and work performance in extreme thermal environments. Trans NY Acad Sci 36: 531‐544, 1974.
 78. Goldman RF, Green EB, Iampietro PF. Tolerance of hot, wet environments by resting men. J Appl Physiol 20: 271‐277, 1965.
 79. Gonzalez‐Alonso J. Separate and combined influences of dehydration and hyperthermia on cardiovascular responses to exercise. Int J Sports Med 19: S111‐S114, 1998.
 80. Gonzalez‐Alonso J, Calbet JAL, Nielsen B. Metabolic and thermodynamic responses to dehydration‐induced reductions in muscle blood flow in exercising humans. J Physiol (London) 520: 577‐589, 1999.
 81. Gonzalez NW, Bernard TE, Carroll NL, Bryner MA, Zeigler JP. Maximum sustainable work rate for five protective clothing ensembles with respect to moisture vapor transmission rate and air permeability. J Occup Environ Hyg 3: 80‐86, 2006.
 82. Gonzalez RR. Biophysical and physiological integration of proper clothing for exercise. Exerc Sport Sci Rev 15: 261‐295, 1987.
 83. Gonzalez RR. Biophysics of heat transfer and clothing considerations. In: Pandolf KB, Sawka MN and Gonzalez RR, editors. Human Performance Physiology and Environmental Medicine in Terrestrial Extremes. Indianapolis: Benchmark Press, 1988, pp. 45‐95.
 84. Gonzalez RR, Cena K. Evaluation of vapor permeation through garments during exercise. J Appl Physiol 58: 928‐935, 1985.
 85. Gonzalez RR, McLellan TM, Withey WR, Chang SK, Pandolf KB. Heat strain models applicable for protective clothing systems: Comparison of core temperature response. J Appl Physiol 83: 1017‐1032, 1997.
 86. Grant SM, Green HJ, Phillips SM, Sutton JR. Effects of acute expansion of plasma volume on cardiovascular and thermal function during prolonged exercise. Eur J Appl Physiol 76: 356‐362, 1997.
 87. Green HJ, Coates G, Sutton JR, Jones S. Early adaptations in gas exchange, cardiac function and haematology to prolonged exercise training in man. Eur J Appl Physiol 63: 17‐23, 1991.
 88. Griefahn B. Acclimation to three different hot climates with equivalent wet bulb globe temperatures. Ergonomics 40: 223‐234, 1997.
 89. Hancock P, Vasmatzidis I. Human occupational and performance limits under stress: The thermal environment as a prototypical example. Ergonomics 41: 1169‐1191, 1998.
 90. Hancock PA, Vasmatzidis I. Effect of heat stress of cognitive performance: The current state of knowledge. Int J Hyperthermia 19: 355‐372, 2003.
 91. Harber P, Shimozaki S, Barret T, Loisides P. Relationship of subjective tolerance of respirator loads to physiologic effects and psychophysical load sensitivity. J Occup Med 31: 681‐686, 1989.
 92. Harber P, Shimozaki S, Barrett T, Losides P, Fine G. Effects of respirator dead space, inspiratory resistance, and expiratory resistance ventilatory loads. Am J Ind Med 16: 189‐198, 1989.
 93. Havenith G. Heat balance when wearing protective clothing. Ann Occup Hyg 43: 289‐296, 1999.
 94. Havenith G, Bröde P, Hartog Ed, Kuklane K, Holmer I, Rossi RM, Richards M, Farnworth B, Wang X. Evaporative cooling: Effective latent heat of evaporation in relation to evaporation distance from the skin. J Appl Physiol 114: 778‐785, 2013.
 95. Havenith G, denHartog E, Martin S. Heat stress in chemical protective clothing: Porosity and vapour resistance. Ergonomics 54: 497‐507, 2011.
 96. Havenith G, Heus R, Lotens WA. Clothing ventilation, vapour resistance and permeability index: Changes due to posture, movement and wind. Ergonomics 33: 989‐1005, 1990.
 97. Havenith G, Heus R, Lotens WA. Resultant clothing insulation: A function of body movement, posture, wind, clothing fit and ensemble thickness. Ergonomics 33: 67‐84, 1990.
 98. Havenith G, Holmer I, Hartog EAd, Parsons KC. Clothing evaporative heat resistance ‐ proposal for improved representation in standards and models. Ann Occup Hyg 43: 339‐346, 1999.
 99. Havenith G, Inoue Y. Age predicts cardiovascular, but not thermoregulatory, responses to humid heat stress. Eur J Appl Physiol 70: 88‐96, 1995.
 100. Havenith G, Luttikholt VGM, Vrijkotte TGM. The relative influence of body characteristics on humid heat stress response. Eur J Appl Physiol 70: 270‐279, 1995.
 101. Havenith G, Richards MG, Wang X, Bröde P, Candas V, denHartog E, Holmér I, Kuklane K, Meinander H, Nocker W. Apparent latent heat of evaporation from clothing: Attenuation and “heat pipe” effects. J Appl Physiol 104: 142‐149, 2008.
 102. Havenith G, vanMiddendorp H. The relative influence of physical fitness, acclimatization state, anthropometric measures and gender on individual reactions to heat stress. Eur J Appl Physiol 61: 419‐427, 1990.
 103. Havenith G, Zhang P, Hatcher K, Daanen H. Comparison of two tracer gas dilution methods for the determination of clothing ventilation and of vapour resistance. Ergonomics 53: 548‐558, 2010.
 104. Headley DB, Brecht‐Clark JM. Sustained operations of artillery crews in NBC and non‐NBC environments. Milit Med 154: 511‐515, 1989.
 105. Henane R, Flandrois R, Charbonnier J. Increase in sweating sensitivity by endurance conditioning in man. J Appl Physiol 43: 822‐828, 1977.
 106. Hermansen L, Vokac Z, Lereim P. Respiratory and circulatory response to added air flow resistance during exercise. Ergonomics 15: 15‐24, 1972.
 107. Hessemer V, Bruck K. Inlfuence of menstrual cycle on thermoregulatory, metabolic, and heart rate responses to exercise at night. J Appl Physiol 59: 1911‐1917, 1985.
 108. Hobson RM, Clapp EL, Watson P, Maughan RJ. Exercise capacity in the heat is greater in the morning than in the evening in man. Med Sci Sports Exerc 41: 174‐180, 2009.
 109. Holmer I. Protective clothing and heat stress. Ergonomics 38: 166‐182, 1995.
 110. Holmér I. Protective clothing in hot environments. Ind Health 44: 404‐413, 2006.
 111. Holmer I. Evaluation of cold workplaces: An overview of standards for assessment of cold stress. Ind Health 47: 228‐234, 2009.
 112. Hopper MK, Coggan AC, and Coyle EF. Exercise stroke volume relative to plasma‐volume expansion. J Appl Physiol 64: 404‐408, 1988.
 113. Horvath SM, Drinkwater BL. Thermoregulation and the menstrual cycle. Aviat Space Environ Med 53: 790‐794, 1982.
 114. House JR. Extremity cooling as a method for reducing heat strain. J Defence Sci 3: 108‐114, 1998.
 115. House JR, Holmes C, Allsopp AJ. Prevention of heat strain by immersing the hands and forearms in water. J Royal Nav Med Serv 83: 26‐30, 1997.
 116.ISO. Ergonomics of the thermal environment ‐ Determination and interpretation of cold stress when using required clothing insulation (IREQ) and local cooling effects. Geneva, 2008.
 117. Jendritzky G, deDear R, Havenith G. UTCI‐why another thermal index? J Biometerol 56: 421‐428, 2012.
 118. Jetté M, Thoden J, Livingstone S. Physiological effects of inspiratory resistance on progressive aerobic work. Eur J Appl Physiol 60: 65‐70, 1990.
 119. Kakitsuba N, Gaul K, Michna H, Mekjavic IB. Dynamic moisture permeation through clothing. Aviat Space Environ Med 59: 49‐53, 1988.
 120. Kamon E, Benson J, Soto K. Scheduling work and rest for the hot ambient conditions with radiant heat source. Ergonomics 26: 181‐192, 1983.
 121. Kampmann B, Bröde P, Schütte M, Griefahn B. Lowering of resting core temperature during acclimation is influenced by exercise stimulus. Eur J Appl Physiol 104: 321‐327, 2008.
 122. Kaufman JW, Fatkin LT. Assessment of Advanced Personal Cooling Systems for use with Chemical Protective Outer Garments. Patuxent River, Maryland: Naval Air Warfare Center Aircraft Division, 2001, pp. 1‐33.
 123. Kenefick RW, O'Moore KM, Mahood NV, Castellani JW. Rapid IV versus oral rehydration: Responses to subsequent exercise heat stress. Med Sci Sports Exerc 38: 2125‐2131, 2006.
 124. Kenney WL. A review of comparative responses of men and women to heat stress. Environ Res 37: 1‐11, 1985.
 125. Kenney WL. Control of heat‐induced vasodilation in relation to age. Eur J Appl Physiol 57: 120‐125, 1988.
 126. Kenny GP, Schissler AR, Stapleton J, Piamonte M, Binder K, Lynn A, Lan CQ, Hardcastle SG. Ice cooling vest on tolerance for exercise under uncompensable heat stress. J Occup Environ Hyg 8: 484‐491, 2011.
 127. Kerslake DM. The stress of hot environments. Monographs Physiol Soc 29: 1‐312, 1972.
 128. Kolka MA, Stephenson LA. Control of sweating during the human menstrual cycle. Eur J Appl Physiol 58: 890‐895, 1989.
 129. Kolka MA, Stephenson LA. Interaction of menstrual cycle phase, clothing resistance and exercise on thermoregulation in women. J Therm Biol 22: 137‐141, 1997.
 130. Krauchi K, Wirz‐Justice A. Circadian rhythm of heat production, heart rate, and skin and core temperature under masking conditions in men. Am J Physiol 267: R819‐R829, 1994.
 131. Latzka WA, Sawka MN, Montain SJ, Skrinar GS, Fielding RA, Matott RP, Pandolf KB. Hyperhydration: Tolerance and cardiovascular effects during uncompensable exercise‐heat stress. J Appl Physiol 84: 1858‐1864, 1998.
 132. Lee DT, Haymes EM. Exercise duration and thermoregulatory responses after whole body precooling. J Appl Physiol 79: 1971‐1976, 1995.
 133. Lee JKW, Shirreffs SM, Maughan RJ. Cold drink ingestion improves exercise endurance capacity in the heat. Med Sci Sports Exerc 40: 1637‐1644, 2008.
 134. Leithead CS, Lind AR. Heat Stress and Heat Disorders. London: Casell, 1964.
 135. Lerman Y, Shefer A, Epstein Y, Keren G. External inspiratory resistance of protective respiratory devices: Effects on physical performance and respiratory function. Am J Ind Med 4: 733‐740, 1983.
 136. Levine L, Sawka M, Gonzalez R. Evaluation of clothing systems to determine heat strain. Amer Ind Hyg Assoc J 59: 557‐562, 1998.
 137. Lewin R, Foley RA. Principles of Human Evolution. Hoboken, New Jersey: Wiley‐Blackwell, 2005.
 138. Livingstone SD, Nolan RW, Cain JB, Keefe AA. Effect of working in hot environments on respiratory air temperatures. Eur J Appl Physiol 69: 98‐101, 1994.
 139. Livingstone SD, Nolan RW, Cattroll SW. Heat loss caused by immersing the hands in water. Aviat Space Environ Med 60: 1166‐1171, 1989.
 140. Livingstone SD, Nolan RW, Keefe AA. Heat loss caused by cooling the feet. Aviat Space Environ Med 66: 232‐237, 1995.
 141. Lotens WA. Criteria for Maximal Acceptable Heat Load. Soesterberg, The Netherlands: TNO, 1978.
 142. Lotens WA. Heat Transfer from Humans Wearing Clothing. Delft, Netherlands: Delft University, 1993.
 143. Lotens WA, Havenith G. Calculation of clothing insulation and vapour resistance. Ergonomics 34: 233‐254, 1991.
 144. Lotens WA, Pieters AMJ. Transfer of radiative heat through clothing ensembles. Ergonomics 38: 1132‐1155, 1995.
 145. Lotens WA, Wammes LJA. Vapour transfer in two‐layer clothing due to diffusion and ventilation. Ergonomics 36: 1223‐1240, 1993.
 146. Louhevaara VA, Smolander J, Tuomi T, Korhonen O, Juhani J. Effects of an SCBA on breathing pattern, gas exchange, and heart rate during exercise. J Occup Med 27: 213‐216, 1985.
 147. Malchaire JBM. Occupational heat stress assessment by the predicted heat strain model. Ind Health 44: 380‐387, 2006.
 148. Malley KS, Goldstein AM, Aldrich TK, Kelly KJ, Weiden M, Coplan N, Karwa ML, Prezant DJ. Effects of fire fighting uniform (modern, modified modern, and traditional) design changes on exercise duration in New York City Firefighters. J Occup Environ Med 41: 1104‐1115, 1999.
 149. Marino FE, Lambert MI, Noakes TD. Superior performance of African runners in warm humid but not in cool environmental conditions. J Appl Physiol 96: 124‐130, 2004.
 150. Marino FE, Mbambo Z, Kortekaas E, Wilson G, Lambert MI, Noakes TD, Dennis SC. Advantages of smaller body mass during distance running in warm, humid environments. Pflugers Arch Eur J Physiol 441: 359‐367, 2000.
 151. McCullough EA. Factors affecting the resistance to heat transfer provided by clothing. Thermal Biol 18: 405‐407, 1993.
 152. McCullough EA, Kenney WL. Thermal insulation and evaporative resistance of football uniforms. Med Sci Sports Exerc 35: 832‐837, 2003.
 153. McLellan TM. Work performance at 40°C with Canadian Forces biological and chemical protective clothing. Aviat Space Environ Med 64: 1094‐1100, 1993.
 154. McLellan TM. Tolerance Times for Continuous Work Tasks while Wearing NBC Protective Clothing in Warm and Hot Environments and the Strategy of Implementing Rest Schedules. Toronto, Ontario: Defence and Civil Institute of Environmental Medicine, 1994, p. 1‐14.
 155. McLellan TM. Heat strain while wearing the current Canadian or a new hot‐weather French NBC protective clothing ensemble. Aviat Space Environ Med 67: 1057‐1062, 1996.
 156. McLellan TM. Sex‐related differences in thermoregulatory responses while wearing protective clothing. Eur J Appl Physiol 78: 28‐37, 1998.
 157. McLellan TM. Chemical‐biological protective clothing: Effects of design and initial state on physiological strain. Aviat Space Environ Med 79: 500‐508, 2008.
 158. McLellan TM, Aoyagi Y. Heat strain in protective clothing following hot‐wet or hot‐dry heat acclimation. Can J Appl Physiol 21: 90‐108, 1996.
 159. McLellan TM, Boscarino C, Duncan EJS. Physiological strain of next generation combat uniforms with chemical and biological protection: Importance of clothing vents. Ergonomics 56: 327‐337, 2013.
 160. McLellan TM, Cheung SS. Impact of fluid replacement on heat storage while wearing protective clothing. Ergonomics 43: 2020‐2030, 2000.
 161. McLellan TM, Gannon GA, Zamecnik J, Gil V, Brown GM. Low doses of melatonin and diurnal effects on thermoregulation and tolerance to uncompensable heat stress. J Appl Physiol 87: 308‐316, 1999.
 162. McLellan TM, Jacobs I, Bain JB. Influence of temperature and metabolic rate on work performance with Canadian Forces NBC clothing. Aviat Space Environ Med 64: 587‐594, 1993.
 163. McLellan TM, Meunier P, Livingstone S. Influence of a new vapor protective clothing layer on physical work tolerance times at 40°C. Aviat Space Environ Med 63: 107‐113, 1992.
 164. McLellan TM, Pope JI, Cain JB, Cheung SS. Effects of metabolic rate and ambient vapour pressure on heat strain in protective clothing. Eur J Appl Physiol 74: 518‐527, 1996.
 165. Millard C, Spilsbury P, Withey W. The effects of heat acclimation on the heat strain of working in protective clothing. In: Frim J, Tikuisis P, Ducharme MB, editors Sixth ICEE. Montebello, Quebec: DCIEM, 1994, p. 80‐81.
 166. Miller V, Bates G, Schneider JD, Thomsen J. Self‐pacing as a protective mechanism against the effects of heat stress. Ann Occup Hyg 55: 548‐555, 2011.
 167. Mitchell JB, Voss KW. The influence of volume on gastric emptying and fluid balance during prolonged exercise. Med Sci Sports Exerc 23: 314‐319, 1991.
 168. Montain SJ, Coyle EF. Fluid ingestion during exercise increases skin blood flow independent of increases in blood volume. J Appl Physiol 73: 903‐910, 1992.
 169. Montain SJ, Coyle EF. Influence of graded dehydration on hyperthermia and cardiovascular drift during exercise. J Appl Physiol 73: 1340‐1350, 1992.
 170. Montain SJ, Latzka WA, Sawka MN. Fluid replacement recommendations for training in hot weather. Mil Med 164: 502‐508, 1999.
 171. Montain SJ, Sawka MN, Cadarette BS, Quigley MD, McKay JM. Physiological tolerance to uncompensable heat stress: Effects of exercise intensity, protective clothing, and climate. J Appl Physiol 77: 216‐222, 1994.
 172. Mora‐Rodriguez R. Influence of aerobic fitness on thermoregulation during exercise in the heat. Exerc Sport Sci Rev 40: 79‐87, 2012.
 173. Moran D, Montain S, Pandolf K. Evaluation of different levels of hydration using a new physiological strain index. Am J Physiol 275: R854‐R860, 1998.
 174. Moran DS, Shapiro Y, Laor A, Izraeli S, Pandolf KB. Can gender differences during exercise‐heat stress be assessed by the physiological strain index? Am J Physiol 276: R1798‐1804, 1999.
 175. Moran DS, Shitzer A, Pandolf KB. A physiological strain index to evaluate heat stress. American Journal of Physiology 275: R129‐R134, 1998.
 176. Morrison SA, Sleivert GG, Cheung SS. Aerobic influence on neuromuscular function and tolerance during passive hyperthermia. Med Sci Sports Exerc 38: 1754‐1761, 2006.
 177. Muza SR, Banderet LE, Cadarette B. Protective uniforms for nuclear, biological and chemical warfare: Metabolic, thermal, respiratory and pyschological issues. In: Pandolf KB, Burr RE, editors. Textbooks of Military Medicine: Medical Aspects of Harsh Environments, Volume 2. Washington D.C.: Office of the Surgeon General at TMM Publications, 2002, pp. 1095‐1138.
 178. Muza SR, Banderet LE, Forte VA. Effects of chemical defense clothing and individual equipment on ventilatory function and subjective reactions. Aviat Space Environ Med 67: 1190‐1197, 1996.
 179. Nadel ER. Control of sweating rate while exercising in the heat. Med Sci Sports Exerc 11: 31‐35, 1979.
 180. Nielsen B. Heat acclimation–mechanisms of adaptation to exercise in the heat. Int J Sports Med 19 (Suppl 2): S154‐S156, 1998.
 181. Nielsen B, Strange S, Christensen NJ, Warberg J, Saltin B. Acute and adaptive responses in humans to exercise in a warm, humid environment. Pflugers Arch Eur J Physiol 434: 49‐56, 1997.
 182. Nielsen R, Olesen BW, Fanger PO. Effect of physical activity and air velocity on the thermal insulation of clothing. Ergonomics 28: 1617‐1631, 1985.
 183. Nishi Y. Measurement of thermal balance of man. In: Cena K, Clark JA, editors. Bioengineering, Thermal Physiology and Comfort. New York, N.Y.: Elsevier Scientific Publishing Co., 1981, pp. 29‐39.
 184. Noakes TD. Hydration in the marathon: Using thirst to gauge safe fluid replacement. Sports Med 37: 463‐466, 2007.
 185. Noakes TD, Rehrer NJ, Maughan RJ. The importance of volume in regulating gastric emptying. Med Sci Sports Exerc 23: 307‐313, 1991.
 186. Nolte HW, Noakes TD, Vuuren BV. Trained humans can exercise safely in extreme dry heat when drinking water ad libitum. J Sport Sci 29: 1233‐1241, 2011.
 187. Nose H, Mack GW, Shi X, Morimoto K, Nadel ER. Effect of saline infusion during exercise on thermal and circulatory regulations. J Appl Physiol 69: 609‐616, 1990.
 188. Nunneley SA. Heat stress in protective clothing: Interactions among physical and physiological factors. Scan J Work Environ Health 15(Suppl 1): 52‐57, 1989.
 189. Nyberg KL, Diller KR, Wissler EH. Automatic control of thermal neutrality for space suit applications using a liquid cooling garment. Aviat Space Environ Med 71: 904‐913, 2000.
 190. Ohnaka T, Tochihara Y, Muramatsu T. Physiological strains in hot‐humid conditions while wering disposable protective clothing commonly used by the asbestos removal industry. Ergonomics 36: 1241‐1250, 1993.
 191. Pandolf KB. Aging and human heat tolerance. Exp Aging Res 23: 69‐105, 1995.
 192. Pandolf KB, Burse RL, Goldman RF. Role of physical fitness in heat acclimatisation, decay and reinduction. Ergonomics 20: 399‐408, 1977.
 193. Pandolf KB, Cadarette BS, Sawka MN, Young AJ. Thermoregulatory responses of middle‐aged and young men during dry‐heat acclimation. J Appl Physiol 65: 65‐71, 1988.
 194. Pandolf KB, Gonzalez JA, Sawka MN, Teal WB, Pimental NA, Constable SH. Tri‐service Perspectives on Microclimate Cooling of Protective Clothing in the Heat. Natick, MA: United States Army Research Institute of Environmental Medicine, 1995.
 195. Pascoe DD, Shanley LA, Smith EW. Clothing and exercise I: Biophysics of heat transfer between the individual, clothing and environment. Sports Med 18: 38‐54, 1994.
 196. Patton J, Bidwell TE, Murphy MM, Mello RP, Harp ME. Energy cost of wearing chemical protective clothing during progressive treadmill walking. Aviat Space Environ Med 66: 238‐242, 1995.
 197. Paull JM, Rosenthal FS. Heat strain and heat stress for workers wearing protective suits at a hazardous waste site. Am Ind Hyg Assoc J 48: 458‐463, 1987.
 198. Périard JD, Caillaud C, Thompson MW. The role of aerobic fitness and exercise intensity on endurance performance in uncompensable heat stress conditions. Eur J Appl Physiol 112: 1989‐1999, 2012.
 199. Porter A. Heat illness and soldiers. Mil Med 158: 606‐609, 1993.
 200. Psikuta A, Frackiewicz‐Kaczmarek J, Frydrych I, Rossi R. Quantitative evaluation of air gap thickness and contact area between body and garment. J Text Res 82: 1405‐1413, 2012.
 201. Raven PB, Moss RF, Page K, Garmon R, Skaggs B. Clinical pulmonary function and industrial respirator wear. Am Ind Hyg Assoc J 42: 897‐903, 1981.
 202. Reffeltrath P. Heat stress reduction of helicopter crew wearing a ventilated vest. Aviat Space Environ Med 77: 545‐550, 2006.
 203. Reneau PD, Bishop PA, Ashley CD. Comparison of a military chemical suit and an industrial usage vapor barrier suit across two thermal environments. Am Ind Hyg Assoc J 58: 646‐649, 1997.
 204. Rissanen S. Quantification of thermal responses while wearing fully encapsulating protective clothing in warm and cold environments. Acta Univer Oulu 486: 1‐71, 1998.
 205. Rissanen S, Jousela I, Jeong JR, Rintamaki H. Heat stress and bulkiness of chemical protective clothing impair performance of medical personnel in basic lifesaving tasks. Ergonomics 51: 1011‐1022, 2008.
 206. Rissanen S, Rintamaki H. Effects of repeated exercise/rest sessions at −10 degrees C on skin and rectal temperatures in men wearing chemical protective clothing. Eur J Appl Physiol 78: 560‐564, 1998.
 207. Rissanen S, Rintamaki H. Cold and heat strain during cold‐weather field training with nuclear, biological, and chemical protective clothing. Mil Med 172: 128‐132, 2007.
 208. Ross ML, Garvican LA, Jeacocke NA, Laursen PB, Abbiss CR, Martin DT, Burke LM. Novel precooling strategy enhances time trial cycling in the heat. Med Sci Sports Exerc 43: 123‐133, 2011.
 209. Roy BD, Green HJ, Grant SM, Tarnopolsky MA. Acute plasma volume expansion alters cardiovascular but not thermal function during moderate intensity prolonged exercise. Can J Physiol Pharmacol 78: 244‐250, 2000.
 210. Sakurada S, Hales JR. A role for gastrointestinal endotoxins in enhancement of heat tolerance by physical fitness. J Appl Physiol 84: 207‐214, 1998.
 211. Saunders AG, Dugas JP, Tucker R, Lambert MI, Noakes TD. The effects of different air velocities on heat storage and body temperature in humans cycling in a hot, humid environment. Acta Physiol Scand 183: 241‐255, 2005.
 212. Sawka MN, Burke LM, Eichner ER, Maughan RJ, Montain SJ, Stachenfeld NS. American College of Sports Medicine position stand. Exercise and fluid replacement. Med Sci Sports Exerc 39: 377‐390, 2007.
 213. Sawka MN, Hubbard RW, Francesconi RP, Horstman DH. Effects of acute plasma volume expansion on altering exercise‐heat performance. Eur J Appl Physiol 51: 302‐312, 1983.
 214. Sawka MN, Latzka WA, Montain SJ, Cadarette BS, Kolka MA, Kraning KK, Gonzalez RR. Physiologic tolerance to uncompensable heat: Intermittent exercise, field vs. laboratory. Med Sci Sports Exerc 33: 422‐430, 2001.
 215. Sawka MN, Young AJ, Latzka WA, Neufer PD, Quigley MD, Pandolf KB. Human tolerance to heat strain during exercise: Influence of hydration. J Appl Physiol 73: 368‐375, 1992.
 216. Selkirk GA, McLellan TM. Influence of aerobic fitness and body fatness on tolerance to uncompensable heat stress. J Appl Physiol 91: 2055‐2063, 2001.
 217. Selkirk GA, McLellan TM. Physical work limits for Toronto firefighters in warm environments. J Occup Environ Hyg 1: 199‐212, 2004.
 218. Selkirk GA, McLellan TM, Wong J. Active versus passive cooling during work in warm environments while wearing firefighting protective clothing. J Occup Environ Hyg 1: 521‐531, 2004.
 219. Selkirk GA, McLellan TM, Wong J. The impact of various rehydration volumes for firefighters wearing protective clothing in warm environments. Ergonomics 15: 418‐433, 2006.
 220. Selkirk GA, McLellan TM, Wright HE, Rhind SG. Mild endotoxemia, NF‐κB translocation, and cytokine increase during exertional heat stress in trained and untrained individuals. Am J Physiol 295: R611‐R623, 2008.
 221. Selkirk GA, McLellan TM, Wright HE, Rhind SG. Expression of intracellular cytokines, HSP72, and apoptosis in monocyte subsets during exertional heat stress in trained and untrained individuals. Am J Physiol 296: R575‐R586, 2009.
 222. Shapiro Y, Pandolf KB, Sawka MN, Toner MM, Winsmann FR, Goldman RF. Auxiliary cooling: Comparison of air‐cooled vs. water‐cooled vests in hot‐dry and hot‐wet environments. Aviat Space Environ Med 53: 785‐789, 1982.
 223. Shkolnik A, Taylor CR, Finch V, Borut A. Why do bedouins wear black robes in hot deserts? Nature 283: 373‐375, 1980.
 224. Shvartz E, Magazanik A, Glick Z. Thermal responses during training in a temperate climate. J Appl Physiol 36: 572‐576, 1974.
 225. Shvartz E, Shapiro Y, Magazanik A, Meroz A, Birnfeld H, Mechtinger A, Shibolet S. Heat acclimation, physical fitness, and responses to exercise in temperature and hot environment. J Appl Physiol 43: 678‐687, 1977.
 226. Siegel R, Maté J, Brearley MB, Watson G, Nosaka K, Laursen PB. Ice slurry ingestion increases core temperature capacity and running time in the heat. Med Sci Sports Exerc 42: 717‐725, 2010.
 227. Siegel R, Maté J, Watson G, Nosaka K, Laursen PB. Pre‐cooling with ice slurry ingestion leads to similar run times to exhaustion in the heat as cold water immersion. J Sport Sci 30: 155‐165, 2012.
 228. Simmons GH, Minson CT, Cracowski J, Halliwill JR. Systemic hypoxia causes cutaneous vasodilation in healthy humans. J Appl Physiol 103: 608‐615, 2007.
 229. Smith DL, Manning TS, Petruzzello SJ. Effect of strenuous live‐fire drills on cardiovascular and psychological responses of recruit firefighters. Ergonomics 44: 244‐254, 2001.
 230. Smith DL, Petruzzello SJ, Kramer JM, Warner SE, Bone BG, Misner JE. Selected physiological and psychobiological responses to physical activity in different configuratons of firefighting gear. Ergonomics 38: 2065‐2077, 1995.
 231. Smolander J, Korhonen O, Ilmarinen R. Responses of young and older men during prolonged exercise in dry and humid heat. J Appl Physiol 61: 413‐418, 1990.
 232. Smolander J, Louhevaara V, Tuomi T, Korhonen O, Jaakkola J. Cardiorespiratory and thermal effects of wearing gas protective clothing. Int Arch Occup Environ Health 54: 261‐270, 1984.
 233. Sparks SA, Cable NT, Doran DA, MacLaren DPM. The influence of environmental temperature on duathlon performance. Ergonomics 48: 1558‐1567, 2005.
 234. Stephenson L, Wenger C, O'Donovan H, Nadel E. Circadian rhythm in sweating and cutaneous blood flow. Am J Physiol 246: R321‐R324, 1984.
 235. Stephenson LA, Vernieuw CR, Leammukda W, Kolka MA. Skin temperature feedback optimizes microclimate cooling. Aviat Space Environ Med 78: 377‐382, 2007.
 236. Sullivan PJ, Mekjavic IB. Temperature and humidity within the clothing microenvironment. Aviat Space Environ Med 63: 186‐192, 1992.
 237. Sullivan PJ, Mekjavic IB, Kakitsuba N. Determination of clothing microenvironment volume. Ergonomics 30: 1043‐1052, 1987.
 238. Tatterson AJ, Hahn AG, Martin DT, Febbraio MA. Effects of heat stress on phsiological responses and exercise performance in elite cyclists. J Sci Med Sport 3: 186‐193, 2000.
 239. Teitlebaum A, Goldman RF. Increased energy cost with multiple clothing layers. J Appl Physiol 32: 743‐744, 1972.
 240. Tenaglia SA, McLellan TM, Klentrou PP. Influence of menstrual cycle and oral contraceptives on tolerance to uncompensable heat stress. Eur J Appl Physiol 80: 76‐83, 1999.
 241. Thompson RL, Hayward JS. Wet‐cold exposure and hypothermia: Thermal and metabolic responses to prolonged exercise in rain. J Appl Physiol 81 1128‐1137, 1996.
 242. Tikuisis P, McLellan TM, Selkirk GA. Physiological vs. perceptional heat strain during exercise‐heat stress. Med Sci Sports Exerc 34: 1454‐1461, 2002.
 243. Tilley RI. Defence Trial 6/425: Performance of Infantry Soldiers Wearing NBC Clothing in Hot/Humid and Hot/Dry Climates. Melbourne, Australia: Materials Research Labs, 1981.
 244. Tilley RI, Standerwick JM, Long GL. Ability of the wet bulb globe temperature index to predict heat stress in men wearing NBC protective clothing. Mil Med 152: 554‐556, 1987.
 245. Tucker R, Rauch L, Harley YXR, Noakes TD. Impaired exercise performance in the heat is associated with an anticipatory reduction in skeletal muscle recruitment. Pflugers Arch Eur J Physiol 448: 422‐430, 2004.
 246. Turpin‐Legendre E, Meyer JP. Comparison of physiological and subjective strain in workers wearing two different protective coveralls for asbestos abatement tasks. Appl Ergonomics 34: 551‐556, 2003.
 247. Ueda H, Inoue Y, Matsudaira M, Araki T, Havenith G. Regional microclimate humidity of clothing during light work as a result of the interaction between local sweat production and ventilation. Int J Clo Sci Technol 18: 225‐234, 2006.
 248. Vogt JJ, Meyer JP, Candas V, Libert JP, Sagot JC. Pumping effects on thermal insulation of clothing worn by subjects. Ergonomics 26: 963‐974, 1983.
 249. Wang F, delFerraro S, Lin LY, Sotto‐Mayor T, Molinaro V, Ribeiro M, Gao C, Kuklane K, Holmér I. Localised boundary air layer and clothing evaporative resistances for individual body segments. Ergonomics 55: 799‐812, 2012
 250. Wang F, Ferraro Sd, Lin LY, Mayor TS, Molinaro V, Ribeiro M, Gao C, Kuklane K, Holmér I. Localised boundary air layer and clothing evaporative resistances for individual body segments. Ergonomics 55: 799‐812, 2012.
 251. Watt MJ, Garnham AP, Febbraio M, Hargreaves M. Effect of acute plasma volume expansion on thermoregulation and exercise performance in the heat. Med Sci Sports Exerc 32: 958‐962, 2000.
 252. Webb P. The physiology of heat regulation. Am J Physiol 268: R838‐R850, 1995.
 253. Weller AS, Linnane DM, Jonkman AG, Daanen HAM. Quantification of the decay and re‐induction of heat acclimation in dry‐heat following 12 and 26 days without exposure to heat stress. Eur J Appl Physiol 102: 57‐66, 2007.
 254. White MK, Hodous TK. Reduced work tolerance associated with wearing protective clothing and respirators. Am Ind Hyg Assoc J 48: 304‐310, 1987.
 255. Williamson R, Cargo J, Luna B, Webbon BW. A thermal physiological comparison of two HAZMAT protective ensembles with and without active convective cooling. J Occup Emerg Med 41: 453‐463, 1999.
 256. Willis BL, Morrow JRJ, Jackson AW, Defina LF, Cooper KH. Secular change in cardiorespiratory fitness of men: Cooper center longitudinal study. Med Sci Sports Exerc 43: 2134‐2139, 2011.
 257. Windle C, Davies N. The effect of fitness on performance in a hot environment wearing normal clothing and when wearing protective clothing. 7th ICEE: 209‐212, 1996.
 258. Wright HE, McLellan TM, Friesen BJ, Casa DJ, Kenny GP. Influence of circulating cytokines on prolactin during slow vs. fast exertional heat stress followed by active or passive recovery. J Appl Physiol 113: 574‐583, 2012.
 259. Wright HE, Selkirk GA, McLellan TM. HPA and SAS responses to increasing core temperature during uncompensable exertional heat stress in trained and untrained males. Eur J Appl Physiol 108: 987‐997, 2010.
 260. Wright HE, Selkirk GA, Rhind SG, McLellan TM. Peripheral markers of central fatigue in trained and untrained during uncompensable heat stress. Eur J Appl Physiol 112: 1047‐1057, 2012.
 261. Wyndham CH. Effect of acclimatization on the sweat rate/rectal temperature relationship. J Appl Physiol 22: 27‐30, 1967.
 262. Young AJ, O'Brien C, Sawka MN, Gonzalez RR. Physiological problems associated with wearing NBC protective clothing during cold weather. Aviat Space Environ Med 71: 184‐189, 2000.
 263. Young AJ, Sawka MN, Quigly MD, Cadarette BS, Neufer PD, Dennis RC, Valeri CR. Role of thermal factors on aerobic capacity improvements with endurance training. J Appl Physiol 75: 49‐54, 1993.

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Tom M. McLellan, Hein A. M. Daanen, Stephen S. Cheung. Encapsulated Environment. Compr Physiol 2013, 3: 1363-1391. doi: 10.1002/cphy.c130002