Abstract
Purpose: We examined whether eccrine sweat glands ion reabsorption rate declined with age in 35 adults aged 50–84 years. Aerobic fitness (VO2max) and salivary aldosterone were measured to see if they modulated ion reabsorption rates. Methods: During a passive heating protocol (lower leg 42 °C water submersion) the maximum ion reabsorption rates from the chest, forearm and thigh were measured, alongside other thermophysiological responses. The maximum ion reabsorption rate was defined as the inflection point in the slope of the relation between galvanic skin conductance and sweat rate. Results: The maximum ion reabsorption rate at the forearm, chest and thigh (0.29 ± 0.16, 0.33 ± 0.15, 0.18 ± 0.16 mg/cm2/min, respectively) were weakly correlated with age (r ≤ − 0.232, P ≥ 0.05) and salivary aldosterone concentrations (r ≤ − 0.180, P ≥ 0.179). A moderate positive correlation was observed between maximum ion reabsorption rate at the thigh and VO2max (r = 0.384, P = 0.015). Salivary aldosterone concentration moderately declined with age (r = − 0.342, P = 0.021). Whole body sweat rate and pilocarpine-induced sudomotor responses to iontophoresis increased with VO2max (r ≥ 0.323, P ≤ 0.027) but only moderate (r = − 0.326, P = 0.032) or no relations (r ≤ − 0.113, P ≥ 0.256) were observed with age. Conclusion: The eccrine sweat glands’ maximum ion reabsorption rate is not affected by age, spanning 50–84 years. Aldosterone concentration in an aged cohort does not appear to modulate the ion reabsorption rate. We provide further support for maintaining cardiorespiratory fitness to attenuate any decline in sudomotor function.
Original language | English |
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Pages (from-to) | 3145-3159 |
Number of pages | 15 |
Journal | European Journal of Applied Physiology |
Volume | 121 |
Issue number | 11 |
Early online date | 9 Aug 2021 |
DOIs | |
Publication status | Published - Nov 2021 |
Bibliographical note
Funding Information:This study was supported by a Grant-in-Aid for Scientific Research (16H04851 and 17H0253) from the Japan Society for the Promotion of Science from the Ministry of Education, Culture, Sports, Science, and Technology of Japan.
Publisher Copyright:
© 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
Keywords
- Age
- Aldosterone
- Elderly
- Passive heating
- Sweat sodium