Publication detail

Maintained hydration status after a 24-h winter mountain running race under extremely cold conditions

CHLÍBKOVÁ, D. NIKOLAIDIS, P. ROSEMANN, T. KNECHTLE, B. BEDNÁŘ, J.

Original Title

Maintained hydration status after a 24-h winter mountain running race under extremely cold conditions

Type

journal article in Web of Science

Language

English

Original Abstract

Background: To date, no study has examined the hydration status of runners competing in a 24-h winter race under extremely cold environmental conditions. Therefore, the aim was to examine the effect of a 24-h race under an average temperature of -14.3 degrees C on hydration status. Methods: Blood and urine parameters and body mass (BM) were assessed in 20 finishers (women, n = 6; men, n = 14) pre- and post-race. Results: Five (25%) ultra-runners had lower pre-race plasma sodium [Na+] and 11 (52%) had higher pre-race plasma potassium [K+] values than the reference ranges. Post-race plasma [Na+], plasma osmolality, urine osmolality and urine specific gravity remained stable (p > 0.05). The estimated fluid intake did not differ (p > 0.05) between women (0.30 +/- 0.06 L/h) and men (0.46 +/- 0.21 L/h). Runners with a higher number of completed ultra-marathons (r = -0.50, p = 0.024) and higher number of training kilometers (r = -0.68, p = 0.001) drank less than those with lower running experience. Pre-race and post-race plasma [Na+] were related to plasma osmolality (r = 0.65, p = 0.002, r = 0.69, p < 0.001, respectively) post-race, but not to fluid intake (p > 0.05). BM significantly decreased post-race (p = 0.002) and was not related to plasma [Na+] or fluid intake (p > 0.05). Post-race hematocrit and plasma [K+] decreased (p < 0.001) and transtubular potassium gradient increased (p = 0.008). Higher pre- race plasma [K+] was related to higher plasma [K+] loss post-race (p = -0.85, p < 0.001). Conclusion: Hydration status remained stable despite the extremely cold winter weather conditions. Overall fluid intake was probably sufficient to replenish the hydration needs of 24-h runners. Current recommendations may be too high for athletes competing in extremely cold conditions.

Keywords

extreme weather conditions, winter, ultra-running, fluid intake, plasma sodium

Authors

CHLÍBKOVÁ, D.; NIKOLAIDIS, P.; ROSEMANN, T.; KNECHTLE, B.; BEDNÁŘ, J.

Released

11. 1. 2019

Publisher

Frontiers

Location

Lausanne Switzerland

ISBN

1664-042X

Periodical

Frontiers in Physiology

Number

9

State

Swiss Confederation

Pages from

1959

Pages to

1969

Pages count

10

URL

https://www.frontiersin.org/articles/10.3389/fphys.2018.01959/full

Full text in the Digital Library

http://hdl.handle.net/11012/193368

BibTex

@article{BUT151948,
  author="Daniela {Chlíbková} and Pantelis T. {Nikolaidis} and Thomas {Rosemann} and Beat {Knechtle} and Josef {Bednář}",
  title="Maintained hydration status after a 24-h winter mountain running race under extremely cold conditions",
  journal="Frontiers in Physiology",
  year="2019",
  number="9",
  pages="1959--1969",
  doi="10.3389/fphys.2018.01959",
  issn="1664-042X",
  url="https://www.frontiersin.org/articles/10.3389/fphys.2018.01959/full"
}