Experiments were undertaken to determine the effects of hydration status on a) orthostatic responses, and on b), relative changes in intravascular volume and protein content, during 70 degrees head-up tilt (HUT). Six men underwent 45 min of HUT, preceded by 45 min supine, first dehydrated, and again 105 min later after rehydration with water. Heart [...]
PURPOSE: Although many studies have attempted to examine the effect of hypohydration on strength, power, and high-intensity endurance, few have successfully isolated changes in total body water from other variables that alter performance (e.g., increased core temperature), and none have documented the influence of hypohydration on an isotonic, multiset, multirepetition exercise bout typical of resistance [...]
Exercise intensity powerfully influences testosterone, cortisol, and testosterone : cortisol ratio (T:C) responses to endurance exercise. Hydration state may also modulate these hormones, and therefore may alter the anabolic/catabolic balance in response to endurance exercise and training. This study examined the effect of running intensity on testosterone, cortisol, and T : C when exercise was [...]
PURPOSE: To assess the hydration status and level of hydration knowledge of youths at summer sports camps. METHODS: Sixty-seven active youths, 57 males (mean +/- SD, 12 +/- 2 y, 136 +/- 16 cm, 50.6 +/- 21.1 kg) and 10 females (13 +/- 2 y, 153 +/- 8 cm, 45.2 +/- 9.0 kg) participated in [...]
The limited literature on the effects of dehydration on human cognitive function is contradictory and inconsistent. Although it has been suggested that decrements in cognitive performance are present in the range of a 2 to 3% reduction in body weight, several dose-response studies indicate dehydration levels of 1% may adversely affect cognitive performance. When a [...]
This study examined the effects of beverage composition on the voluntary drinking pattern, body fluid balance and body temperature responses of heat-acclimatized trained girls exercising intermittently in outdoor conditions (WBGT = 30.9 +/- 0.2 degrees C). Twelve trained, heat-acclimatized girls (age = 10.6 +/- 0.2 years) performed three 3-h sessions, each consisting of four 20-min [...]
There is a rich scientific literature regarding hydration status and physical function that began in the late 1800s, although the relationship was likely apparent centuries before that. A decrease in body water from normal levels (often referred to as dehydration or hypohydration) provokes changes in cardiovascular, thermoregulatory, metabolic, and central nervous function that become increasingly [...]
Eighty-six children in Florida died of complications associated with diarrhea between 1985 and 1990, deaths which constituted an important preventable fraction of infant mortality. The state will support health professionals in reducing the number of hospitalizations and deaths due to diarrheal complications, Governor Lawton Chiles announced in September 1991, and the Florida Department of Health [...]
This paper compares the hydration ability of three commercially-available sports drinks with water under conditions of rest and exercise, using a deuterium dilution technique. For the rest group, 0.05g/kg of body weight of deuterium, contained in gelatine capsules, was ingested with one of the test solutions and saliva samples were collected every five minutes for [...]
No abstract available.