Abstract
Eight older (60–65 years) and six younger (20–25 years) men were exposed to a standard heat stress for 60 min in summer, autumn, winter, and spring. The test consisted of placing the lower legs and feet in a 42°C water bath while sitting in constant environmental conditions (30°C and 45% relative humidity). The increase of rectal temperature (ΔT re) was significantly greater (P < 0.05) in autumn, winter, and spring than in summer for the older group, but significantly greater only in winter than in summer for the younger group (P < 0.05). The ΔT re was greater for the older group in all seasons, but of significance only in autumn and spring (P < 0.01). There were no significant season-related differences for metabolic heat production (m) and mean skin temperature (\(\overline T \) sk) during the heat test in the respective groups, although the m and\(\overline T \) sk were lower for the older group in all seasons (P < 0.01). In the older group total body sweating rate (msw) divided by ΔT re (total msw/ΔT re) decreased from summer to winter (P < 0.02) and did not differ between winter and spring, whereas total msw/ΔT re in the younger group increased in spring after decreasing from autumn to winter (P < 0.03). The variations of the value, local sweating rate on the back and thigh divided by ΔT re (back msw/ΔT re and thigh msw/ΔT re), were similar to those of the total msw/ΔT re in each group, except for back msw/ΔT re in the younger group, which did not increase from winter to spring. The total msw/ΔT re, back msw/ΔT re and thigh msw/ΔT re were significantly less for the older group in summer, autumn and spring (P < 0.05). The range of seasonal variations was significantly less for the older group (P < 0.001). The results indicated that, compared with younger men in older men, the enhancement of sweating function toward summer occurred later and its reduction toward winter occurred earlier despite a smaller range of seasonal variation and that older men had a somewhat lesser capability to maintainT re when challenged by heat stress in all seasons.
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References
Anderson RK, Kenney WL (1987) Effect of age on heat-activated sweat gland density and flow during exercise in dry heat. J Appl Physiol 63:1089–1094
Araki T, Inoue Y, Umeno K (1980) Effects of physical training on thermoregulatory responses to alternate stress of heat and cold. Jpn J Phys Fitness Sports Med 29:75–81
Araki T, Matsushita K, Umeno K, Tsujino A, Toda Y (1981) Effect of physical training on exercise-induced sweating in women. J Appl Physiol 51:1526–1532
Collins KJ (1966) The action of exogenous aldosterone on the secretion and composition of drug-induced sweat. Clin Sci 30:207–221
Crowe JP, Moore RE (1973) Physiological and behavioral responses of aged men to passive heating. J Physiol (Lond) 236:43–45
Drinkwater BL, Bedi JF, Loucks AB, Horvath SM (1982) Sweating senstivity and capacity of women in relation to age. J Appl Physiol 53:671–676
Fujimoto S, Watanabe T (1969) Studies on the body surface area of Japanese. Acta Med Nagasaki 13:1–13
Hardy RF, DuBois EF (1937) Regulation of heat loss from the human body. Proc Nat Acad Sci (Washington) 23:624–631
Hellon RF, Lind AR (1956) Observations on the activity of sweat glands with special reference to the influence of aging. J Physiol (Lond) 133:132–144
Henane R, Bittel J (1975) Change of thermal balance induced by passive heating in resting man. J Appl Physil 38:294–299
Ihzuka H, Hori S, Akamatsu T (1986) Seasonal variations of physiological responses to heat of subtropical and temperature natives. Int J Biometeor 30:107–113
Inoue Y, Nakao M, Matsushita K, Murakami H (1989) A practical method for estimating total oxygen uptake during exercise in elderly men. J Human Ergol 18:13–22
Inoue Y, Nakao M, Araki T, Murakami H (1991) Regional differences in the sweating responses of older and younger men. J Appl Physiol 71:2453–2459
Inoue Y, Nakao M, Araki T, Ueda H (1992) Thermoregulatory responses of young and older men to cold exposure. Eur J Appl Physiol 65:492–498
Kenney WL, Fowler SR (1988) Methylcholine-activated eccrine sweat gland density and output as a function of age. J Appl Physiol 65:1082–1086
Kirby CR, Convertino VA (1986) Plasma aldosterone and sweat sodium concentration after exercise and heat acclimation. J Appl Physiol 61:967–970
Nadel ER, Pandolf KB, Roberts MF, Stolwijik JAJ (1974) Mechanisms of thermal acclimation to exercise and heat. J Appl Physiol 37:515–520
Ogata K (1973) Adaptation (in Japanese). Ishiyaku, Tokyo, pp 59–76
Ohara K (1966) Chloride concentration in sweat, its individual, regional, seasonal and some other variations, and interrelations between them. Jpn J Physiol 16:274–290
Roberts MF, Wenger CB, Stolwijik JAJ, Nadel ER (1977) Skin blood flow and sweating changes following exercise training and heat acclimation. J Appl Physiol 43:133–137
Sagawa S, Shiraki K, Yousef MK, Miki K (1988) Sweating and cardiovascular responses of aged men to heat exposure. J Gerontol 43: M1–8
Sato K (1977) The physiology, pharmacology, and biochemistry of the eccrine sweat gland. Rev Physiol Biochem Pharmacol 79:51–131
Shoenfeld Y, Udassin R, Shapiro Y, Ohri A, Sohar E (1978) Age and sex differences in response to short exposure to extreme dry heat. J Appl Physiol 44:1–4
Smolander J, Korhonen O, Ilmarinen R (1990) Responses of young and older men during prolonged exercise in dry and humid heat. Eur J Appl Physiol 61:413–418
Wyndham CH (1967) Effect of acclimatization on the sweat rate/rectal temperature relationship. J Appl Physiol 22:27–30
Yousef MK, Dill DB, Vitez TS, Hillyard SD, Goldman AS (1984) Thermoregulatory responses to desert heat: age, race and sex. J Gerontol 39:406–414
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Inoue, Y., Nakao, M., Okudaira, S. et al. Seasonal variation in sweating responses of older and younger men. Europ. J. Appl. Physiol. 70, 6–12 (1995). https://doi.org/10.1007/BF00601802
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DOI: https://doi.org/10.1007/BF00601802