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) [...]
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 [...]
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 [...]
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 [...]
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 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 [...]
1. Heat acclimation was induced in eight subjects by asking them to exercise until exhaustion at 60% of maximum oxygen consumption rate (VO2) for 9-12 consecutive days at an ambient temperature of 40 degrees C, with 10% relative humidity (RH). Five control subjects exercised similarly in a cool environment, 20 degrees C, for 90 min for 9-12 days; of these, three [...]
CONTEXT: Time allowing, euhydration can be achieved in the vast majority of individuals by drinking and eating normal beverages and meals. Important to the competitive athlete is prevention and treatment of dehydration and exercise-associated muscle cramps, as they are linked to a decline in athletic performance. Intravenous (IV) prehydration and rehydration has been proposed as [...]
This study investigated the hypothesis that addition of Na+ to a rehydration beverage would stimulate drinking and augment restoration of body water in individuals dehydrated during 90 min of continuous treadmill exercise in the heat. Following a 3.0 +/- 0.2% decrease in body weight (BW), 6 subjects sat in a thermoneutral environment for 30 min to allow [...]
BACKGROUND: Marathon running has become popular, particularly among inexperienced runners. HYPOTHESIS: Many marathoners are inexperienced and lack concern for potential complications of marathon running. STUDY DESIGN: Cross-sectional survey. METHODS: In sum, 419 runners completed a survey on a variety of topics regarding training for a marathon and hydration strategies. RESULTS: Overall, 211 females (38.3 ± [...]