We compared the effect of glycerol-induced hyperhydration (GIH) to that of water-induced hyperhydration (WIH) on cardiovascular and thermoregulatory functions and endurance performance (EP) during prolonged cycling in a temperate climate in subjects consuming fluid during exercise. At weekly intervals, 6 trained male subjects ingested, in a randomized, double-blind, counterbalanced fashion, either a glycerol (1.2 g [...]

The cardiovascular response to standing (sit-to-stand change in heart rate; SSΔHR) is commonly employed as a screening tool to detect hypohydration (body water deficit). No study has systematically evaluated SSΔHR cut points using different magnitudes or different types of controlled hypohydration. The objective of this study was to determine the diagnostic accuracy of the often [...]

The quantitative and qualitative estimation of total body fluid content has proven to be crucial for both diagnosis and prognosis assessment in patients with heart failure. The aim of this review is to summarize the current techniques for assessing body hydration status as well as the principal biomarkers associated with acute heart failure (AHF). Although [...]

Dehydration can affect the volume of brain structures, which might imply a confound in volumetric and morphometric studies of normal or diseased brain. Six young, healthy volunteers were repeatedly investigated using three-dimensional T(1)-weighted magnetic resonance imaging during states of normal hydration, hyperhydration, and dehydration to assess volume changes in gray matter (GM), white matter (WM), [...]

BACKGROUND: It was previously demonstrated that drinking water significantly elevates the resting energy expenditure(REE) in adults, and that low water intake is associated with obesity and lesser success in weight reduction. This study addressed the potential of water drinking to increase the REE in children, as an additional tool for weight management. OBJECTIVE: To examine [...]

This study examined whether drinking of water with breakfast affects the feelings of satiety and hunger, and how long after the meal this effect is maintained. Eight healthy, normal-weight women had three breakfasts with two extra glasses (4 dl) of water and three similar breakfasts without water. The breakfasts were served on three successive mornings during a 2 week period. The subjects filled in forms with visual analogue [...]

BACKGROUND: Secondary school students often do not drink sufficient quantities of water during the school day to prevent dehydration, promote learning and good health. The study aimed to measure the effect of health promotion and the free provision of cooled filtered water on the consumption of water and soft drinks. It also aimed to explore students' views of drinking water provision. METHODS: A study was conducted with three secondary schools in North Tyne side. [...]

OBJECTIVE: The study tested whether a combined environmental and educational intervention solely promoting water consumption was effective in preventing overweight among children in elementary school. METHODS: The participants in this randomized, controlled cluster trial were second- and third-graders from 32 elementary schools in socially deprived areas of 2 German cities. Water fountains were installed and [...]

Levels of thirst and ad libitum drinking decrease with advancing age, making older people vulnerable to dehydration. This study investigated age-related changes in brain responses to thirst and drinking in healthy men. Thirst was induced with hypertonic infusions (3.1 ml/kg 0.51M NaCl) in young (Y) and older (O) subjects. Regional cerebral blood flow (rCBF) was measured with positron emission tomography (PET). Thirst activations were identified by correlating rCBF with thirst ratings. Average rCBF was measured from regions [...]

To determine how the sodium content of ingested fluids affects drinking and the restoration of the body fluid compartments after dehydration, we studied six subjects during 4 h of recovery from 90-110 min of a heat [36 degrees C, less than 30% relative humidity (rh)] and exercise (40% maximal aerobic power) exposure, which caused body [...]