Tags

Type your tag names separated by a space and hit enter

Heat acclimation causes a linear decrease in sweat sodium ion concentration.
J Therm Biol. 2018 Jan; 71:237-240.JT

Abstract

The purpose of this study was to determine the time course for the previously reported reduction in sweat sodium ion concentration during heat acclimation. Four healthy volunteers completed 7 consecutive days of heat acclimation which included 2h of treadmill walking in a 40°C and 40% relative humidity environment. A modified constant hyperthermia protocol was used as workloads were increased each day to maintain a constant core temperature over the 7 days of heat acclimation. Forearm sweat was collected 3 times during each 2h exercise bout on days 1, 3, 5, and 7 of heat acclimation. Forearm sweat rate and sweat sodium ion concentration were determined from each sample. The results showed that there was a significant (p < 0.05) downward shift in the mean sweat rate vs. sweat sodium ion concentration relationship on days 3, 5, and 7 of heat acclimation, as compared to the pre-heat acclimation (day 1) data. Thus, at any given sweat rate, heat acclimation resulted in a significantly lower sweat sodium ion concentration. The response was very rapid and occurred following only 2 consecutive days of heat exposure (i.e., day 3 vs. day 1 data). Furthermore, the calculated sweat sodium ion concentration, at a sweat rate of 1µl/cm2/min, decreased linearly (r = - 0.50, p < 0.05) during the 7 days of heat acclimation. Such results suggest that heat acclimation rapidly improves sodium ion reabsorption from the eccrine sweat gland duct as evidenced by significant reductions in the sweat sodium ion concentration.

Authors+Show Affiliations

School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA 92182, USA; The Department of Biology, San Diego State University, San Diego, CA 92182, USA. Electronic address: mbuono@mail.sdsu.edu.School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA 92182, USA.School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA 92182, USA.School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA 92182, USA.School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA 92182, USA.School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA 92182, USA.School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA 92182, USA.

Pub Type(s)

Journal Article

Language

eng

PubMed ID

29301696

Citation

Buono, Michael J., et al. "Heat Acclimation Causes a Linear Decrease in Sweat Sodium Ion Concentration." Journal of Thermal Biology, vol. 71, 2018, pp. 237-240.
Buono MJ, Kolding M, Leslie E, et al. Heat acclimation causes a linear decrease in sweat sodium ion concentration. J Therm Biol. 2018;71:237-240.
Buono, M. J., Kolding, M., Leslie, E., Moreno, D., Norwood, S., Ordille, A., & Weller, R. (2018). Heat acclimation causes a linear decrease in sweat sodium ion concentration. Journal of Thermal Biology, 71, 237-240. https://doi.org/10.1016/j.jtherbio.2017.12.001
Buono MJ, et al. Heat Acclimation Causes a Linear Decrease in Sweat Sodium Ion Concentration. J Therm Biol. 2018;71:237-240. PubMed PMID: 29301696.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Heat acclimation causes a linear decrease in sweat sodium ion concentration. AU - Buono,Michael J, AU - Kolding,Mark, AU - Leslie,Eric, AU - Moreno,Daniel, AU - Norwood,Sarah, AU - Ordille,Andrew, AU - Weller,Rebecca, Y1 - 2017/12/11/ PY - 2017/08/21/received PY - 2017/11/27/revised PY - 2017/12/06/accepted PY - 2018/1/6/entrez PY - 2018/1/6/pubmed PY - 2018/7/28/medline KW - Eccrine gland KW - Heat acclimation KW - Sweat sodium ion concentration KW - Thermoregulation SP - 237 EP - 240 JF - Journal of thermal biology JO - J. Therm. Biol. VL - 71 N2 - The purpose of this study was to determine the time course for the previously reported reduction in sweat sodium ion concentration during heat acclimation. Four healthy volunteers completed 7 consecutive days of heat acclimation which included 2h of treadmill walking in a 40°C and 40% relative humidity environment. A modified constant hyperthermia protocol was used as workloads were increased each day to maintain a constant core temperature over the 7 days of heat acclimation. Forearm sweat was collected 3 times during each 2h exercise bout on days 1, 3, 5, and 7 of heat acclimation. Forearm sweat rate and sweat sodium ion concentration were determined from each sample. The results showed that there was a significant (p < 0.05) downward shift in the mean sweat rate vs. sweat sodium ion concentration relationship on days 3, 5, and 7 of heat acclimation, as compared to the pre-heat acclimation (day 1) data. Thus, at any given sweat rate, heat acclimation resulted in a significantly lower sweat sodium ion concentration. The response was very rapid and occurred following only 2 consecutive days of heat exposure (i.e., day 3 vs. day 1 data). Furthermore, the calculated sweat sodium ion concentration, at a sweat rate of 1µl/cm2/min, decreased linearly (r = - 0.50, p < 0.05) during the 7 days of heat acclimation. Such results suggest that heat acclimation rapidly improves sodium ion reabsorption from the eccrine sweat gland duct as evidenced by significant reductions in the sweat sodium ion concentration. SN - 0306-4565 UR - https://www.unboundmedicine.com/medline/citation/29301696/Heat_acclimation_causes_a_linear_decrease_in_sweat_sodium_ion_concentration_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0306-4565(17)30349-2 DB - PRIME DP - Unbound Medicine ER -