Urine specific gravity (USG) is used as an index of hydration status. Many studies have used USG to estimate pre-exercise hydration in athletes. However, very little is known about the pre-exercise hydration status of recreational exercisers. The purpose of the present study was to measure the pre-exercise USG in a large sample of recreational exercisers who attended 2 different fitness centers [...]
The purpose of this study was to determine the effects of beverage temperature and composition on weight retention and fluid balance upon voluntary drinking following exercise induced-dehydration. Eight men who were not acclimated to heat participated in four randomly ordered testing sessions. In each session, the subjects ran on a treadmill in a chamber maintained [...]
This study examined the effect of glycerol ingestion on fluid homeostasis, thermoregulation, and metabolism during rest and exercise. Six endurance-trained men ingested either 1 g glycerol in 20 ml H2O x kg(-1) body weight (bw) (GLY) or 20 ml H2O x kg(-1) bw (CON) in a randomized double-blind fashion, 120 min prior to undertaking 90 min of steady state cycle exercise(SS) [...]
Total water intake is seldom reported in dietary surveys and hydration status is rarely measured. Although adequate intake (AI) levels have been suggested by the European Food Safety Authority, the World Health Organization and the Institute of Medicine, uncertainties and confused messages abound regarding optimum intake. This paper reviews data on water intake internationally and [...]
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 [...]
Background and aims: Fluid requirements of children vary as a function of gender and age. To our knowledge, there is very little literature on the hydration status of Italian children. We assessed morning hydration status in a large sample of 515 Italian school children aged 9 to 11 years. Methods: Recruited children completed a questionnaire [...]
Three relatively fit subjects performed duplicate 20- to 25-min cycle ergometer exercise bouts at moderate and heavy intensities (40% and 70% Vo2 max) in ambient temperatures of 20, 26, and 36 degrees C. They approached a steady state in internal body temperature (Tes) in all but the heavy exercise in the heat, where Tes rose consistently, averaging 38.84 degrees C at the termination of exercise. [...]
"BACKGROUND: Muscle contraction during short intervals of intense exercise causes oxidative stress, which can play a role in the development of overtraining symptoms, including increased fatigue, resulting in muscle microinjury or inflammation. Recently it has been said that hydrogen can function as antioxidant, so we investigated the effect of hydrogen-rich water (HW) on oxidative stress [...]