Publication detail

Fluid metabolism in athletes running seven marathons in seven consecutive days

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

Original Title

Fluid metabolism in athletes running seven marathons in seven consecutive days

Type

journal article in Web of Science

Language

English

Original Abstract

Purpose: Hypohydration and hyperhydration are significant disorders of fluid metabolism in endurance performance; however, little relevant data exist regarding multi-stage endurance activities. The aim of the present study was to examine the effect of running seven marathons in 7 consecutive days on selected anthropometric, hematological and biochemical characteristics with an emphasis on hydration status. Methods: Participants included 6 women and 20 men (age 42.6 +/- 6.2 years). Data was collected before day 1 (B-1) and after day 1 (A(1)), 4 (A(4)), and 7 (A(7)). Results: The average marathon race time was 4:44 h:min (ranging from 3:09 - 6:19 h:min). Plasma sodium, plasma potassium and urine sodium were maintained during the race. Body mass (p < 0.001, eta(2) = 0.501), body fat (p < 0.001, eta(2) = 0.572) and hematocrit (p < 0.001 ,eta(2) = 0.358) decreased. Plasma osmolality (Posm) (p < 0.001, eta(2) = 0.416), urine osmolality (Uosm) (p 0.001, eta(2) = 0.465), urine potassium (p < 0.001, eta(2) = 0.507), urine specific gravity (Usg) (p < 0.001, eta(2) 0.540), plasma urea (PUN) (p < 0.001, eta(2) = 0.586), urine urea (UUN) (p < 0.001, if eta(2) = 0.532) and transtubular potassium gradient (p < 0.001, eta(2) = 0.560) increased at A1, A4, and A7 vs. B1. Posm correlated with PUN at A(1) (r = 0.59, p = 0.001) and A(4) (r = 0.58, p = 0.002). The reported post-race fluid intake was 0.5 +/- 0.2 L/h and it correlated negatively with plasma [Na+] (r = -0.42, p = 0.007) at A(4) and (r = -0.50, p = 0.009) at A(7). Uosm was associated with UUN at A(1) (r = 0.80, p < 0.001), at A(4) (r = 0.81, p < 0.001) and at A(7) (r = 0.86, p < 0.001) and with Usg (r = 0.71, p < 0.001) at A(1), (r = 0.52, p = 0.006) at A(4) and (r = 0.46, p = 0.02) at A(7). Conclusions: Despite the decrease in body mass, fluid and electrolyte balance was maintained with no decrease in plasma volume after running seven marathons in seven consecutive days. Current findings support the hypothesis that body mass changes do not reflect changes in the hydration status during prolonged exercise.

Keywords

multi-stage marathon, endurance, running, hydration status, sodium

Authors

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

Released

12. 2. 2018

Publisher

Frontiers

Location

Lausanne Switzerland

ISBN

1664-042X

Periodical

Frontiers in Physiology

Year of study

9

Number

91

State

Swiss Confederation

Pages from

1

Pages to

12

Pages count

12

URL

http://journal.frontiersin.org/article/10.3389/fphys.2018.00091/full

Full text in the Digital Library

http://hdl.handle.net/11012/187193

BibTex

@article{BUT146012,
  author="Daniela {Chlíbková} and Pantelis T. {Nikolaidis} and Thomas {Rosemann} and Beat {Knechtle} and Josef {Bednář}",
  title="Fluid metabolism in athletes running seven marathons in seven consecutive days",
  journal="Frontiers in Physiology",
  year="2018",
  volume="9",
  number="91",
  pages="1--12",
  doi="10.3389/fphys.2018.00091",
  issn="1664-042X",
  url="http://journal.frontiersin.org/article/10.3389/fphys.2018.00091/full"
}