Post-exercise rehydration in man : effects of volume consumed and drink sodium content

The interaction between the volume and composition of fluids ingested was investigated in terms of rehydration effectiveness. Twelve male volunteers, dehydrated by 2.06 +/- 0.02% (mean +/- SE) of body mass by intermittent cycle exercise, consumed a different drink volume on four separate weeks; six...

Full description

Saved in:
Bibliographic Details
Published in:Medicine and science in sports and exercise 1996-10, Vol.28 (10), p.1260-1271
Main Authors: SHIRREFFS, S. M, TAYLOR, A. J, LEIPER, J. B, MAUGHAN, R. J
Format: Article
Language:English
Subjects:
Adult
Beverages - analysis
Biological and medical sciences
Chlorides - analysis
Dehydration - blood
Dehydration - therapy
Dehydration - urine
Exercise - physiology
Fluid Therapy
Fundamental and applied biological sciences. Psychology
Hormones - blood
Humans
Male
Metabolisms and neurohumoral controls
Potassium - analysis
Sodium - analysis
Space life sciences
Vertebrates: anatomy and physiology, studies on body, several organs or systems
Water and mineral metabolism. Osmoregulation. Acidobasic balance
Water-Electrolyte Balance
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The interaction between the volume and composition of fluids ingested was investigated in terms of rehydration effectiveness. Twelve male volunteers, dehydrated by 2.06 +/- 0.02% (mean +/- SE) of body mass by intermittent cycle exercise, consumed a different drink volume on four separate weeks; six subjects received drink L (23 mmol.l-1 Na+) in each trial and six were given drink H (61 mmol.l-1 Na+). Volumes consumed were equivalent to 50%, 100%, 150%, and 200% of body mass loss (trials A, B, C, and D, respectively). Blood and urine samples were obtained before exercise and for 7.5 h after exercise. Less urine was excreted following rehydration in trial A than in all other trials. Cumulative urine output (median ml) was less in trial B (493, range 181-731) than D (1361, range 1014-1984), which was not different from trial C (867, range 263-1191) in group L. In group H, the volume excreted in trial B (260, range 137-376) was less than trials C (602, range 350-994) and D (1001, range 714-1425), and the volume in trial C was less than in trial D. These results suggest that both sodium concentration and fluid volume consumed interact to affect the rehydration process. A drink volume greater than sweat loss during exercise must be ingested to restore fluid balance, but unless the sodium content of the beverage is sufficiently high this will merely result in an increased urinary output.
ISSN:0195-9131
1530-0315
DOI:10.1097/00005768-199610000-00009