Journal of Sports Science and Medicine
Journal of Sports Science and Medicine
ISSN: 1303 - 2968   
Ios-APP Journal of Sports Science and Medicine
Androit-APP Journal of Sports Science and Medicine
Views
5649
Download
156
from September 2014
 
©Journal of Sports Science and Medicine (2005) 04, 422 - 429

Research article
Immediate Re-Hydration Post-Exercise is Not Coincident with Raised Mean Arterial Pressure Over A 30-Minute Observation Period
Bartholomew Kay1, , Brendan J. O'Brien2, Nicholas D. Gill3
Author Information
1 Massey University, Institute of Food, Nutrition, and Human Health, Palmerston North, New Zealand
2 University of Ballarat, School of Human Movement and Sport Sciences, Ballarat, Australia
3 Waikato Institute of Technology, School of Sport and Exercise Science, Hamilton, New Zealand

Bartholomew Kay
✉ Massey University, Institute of Food, Nutrition, and Human Health, Pvt Bag 11222, Palmerston North 5301, New Zealand.
Email: b.kay@massey.ac.nz
Publish Date
Received: 02-05-2005
Accepted: 29-08-2005
Published (online): 01-12-2005
Share this article
 
 
ABSTRACT

This investigation assessed the effects of immediate or delayed re-hydration post-exercise, on mean arterial blood pressure (MAP) and on blood plasma volume (PV) expansion post-exercise. It was hypothesised that fluid ingestion would raise MAP and attenuate PV expansion. On two occasions separated by seven days, eight males (age 20.4 ± 1.7 years, mass 79 ± 5 kg [means ± SD]; VO2max 48 ± 11 mL·kg-1·minute-1, [mean ± SE]) cycled in the heat (35°C, 50% relative humidity) at a power output associated with 50% VO2max, until 1.0kg body mass was lost. 1L water was given either immediately thereafter, or two hours post-exercise by random assignment. On both occasions, MAP was calculated every five minutes for a period of 30-minutes post-exercise, and change in PV was calculated 24-hours post-exercise. Repeated measures ANOVA for MAP results suggested a low probability of a treatment effect (p = 0.655), a high probability of a time effect (p = 0.006), and a moderately high probability of a time x treatment interaction (p = 0.076); MAP tended to be lower when fluid had been consumed. PV expansions 24-hours post-exercise were not significant changes with respect to zero, and were not significantly different by treatment condition. In conclusion: (a) The exercise was not sufficient to elicit significant PV expansions; thus, we were unable to determine the effects of the timing of post-exercise re-hydration on PV expansion. (b) The hypothesis regarding MAP in response to drinking was not supported, rather there was a 92% probability that the inverse affect occurs.

Key words: Dehydration, re-hydration, blood pressure, plasma volume


           Key Points
  • Post exercise hypotension is perhaps the most important mediator of plasma volume expansion post exercise
  • It was hypothesised that drinking water immediately post exercise would attenuate post exercise hypotension by rapidly ameliorating dehydration
  • We found that not only was our hypothesis incorrect, but rather a 92% probability exists that the inverse is true, i.e. drinking water in fact leads to lowered blood pressure, as compared to not drinking.
 
 
Home Issues About Authors
Contact Current Editorial board Authors instructions
Email alerts In Press Mission For Reviewers
Archive Scope
Supplements Statistics
Most Read Articles
  Most Cited Articles
 
  
 
JSSM | Copyright 2001-2020 | All rights reserved. | LEGAL NOTICES | Publisher

It is forbidden the total or partial reproduction of this web site and the published materials, the treatment of its database, any kind of transition and for any means, either electronic, mechanic or other methods, without the previous written permission of the JSSM.

This work is licensed under a Creative Commons License Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.